ANKFY1

UniProt ID: Q9P2R3
Organism: Homo sapiens
Review Status: COMPLETE
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Gene Description

ANKFY1 encodes Rabankyrin-5, a large ankyrin-repeat, BTB/POZ, and FYVE-domain protein that acts on PI3P- and Rab5-positive endosomal membranes. It binds activated Rab5-family GTPases and phosphatidylinositol phosphate lipids to regulate early endosome fusion, macropinocytosis, retromer-dependent endosome-to-Golgi and Golgi-to-lysosome trafficking, and receptor internalization. Recent work shows that ANKFY1 also recruits and stabilizes ATG2A on PI3P-rich endosomal membranes during autophagy, promoting ATG2A-mediated lipid transfer from endosomes to phagophores for autophagosome growth and completion.

Existing Annotations Review

GO Term Evidence Action Reason
GO:0010008 endosome membrane
IBA
GO_REF:0000033
ACCEPT
Summary: Endosome membrane localization/activity is well supported for ANKFY1/Rabankyrin-5.
Reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes on early/endosomal membranes; this location is central to its endosomal trafficking and ATG2A-bridging roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0031267 small GTPase binding
IBA
GO_REF:0000033
ACCEPT
Summary: Small GTPase binding is directly supported by Rab5 and RhoD/RAB-family interaction evidence.
Reason: Rabankyrin-5 was identified as a GTP-dependent Rab5 effector, and additional disease/trafficking work supports interaction with RAB5-regulatory machinery; this is a core molecular function.
Supporting Evidence:
PMID:15328530
Rabankyrin-5 binds to Rab5 specifically, directly, and GTP dependently
PMID:24102721
RhoD binds to the Rab5 effector Rabankyrin-5
PMID:29959197
GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5
GO:0042147 retrograde transport, endosome to Golgi
IBA
GO_REF:0000033
ACCEPT
Summary: Endosome-to-Golgi retrograde transport is supported by Rank-5/retromer evidence.
Reason: Rank-5 interacts and colocalizes with retromer cargo-recognition components, and Rank-5 depletion impairs mannose 6-phosphate receptor retrieval from endosomes to the Golgi.
Supporting Evidence:
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:22284051
depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
GO:0090160 Golgi to lysosome transport
IBA
GO_REF:0000033
ACCEPT
Summary: Golgi-to-lysosome/biosynthetic transport is supported as part of the Rank-5 retromer-trafficking phenotype.
Reason: The same Rank-5 depletion experiments that disrupt retromer distribution also affect biosynthetic transport, consistent with a role in endosome/Golgi/lysosome trafficking.
Supporting Evidence:
PMID:22284051
depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
GO:0005737 cytoplasm
IEA
GO_REF:0000044
KEEP AS NON CORE
Summary: Cytoplasmic localization is supported but is less informative than endosome-membrane localization.
Reason: ANKFY1 was initially described as a cytoplasmic protein and is present in soluble fractions, but the biologically informative location is its recruitment to PI3P/Rab5-positive endosomal membranes.
Supporting Evidence:
PMID:10940552
Ankhzn protein is ubiquitously expressed in a spatiotemporal-specific manner and is located on endosomes
PMID:10940552
present in both membrane and soluble fractions obtained on subcellular fractionation
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
GO:0005768 endosome
IEA
GO_REF:0000117
ACCEPT
Summary: Endosome localization is supported and relevant to ANKFY1 function.
Reason: The original ANKHZN paper and later Rabankyrin-5 studies place the protein on endosomes, where it binds Rab5/PI3P and coordinates endocytic trafficking.
Supporting Evidence:
PMID:10940552
Ankhzn protein is ubiquitously expressed in a spatiotemporal-specific manner and is located on endosomes
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
GO:0005769 early endosome
IEA
GO_REF:0000044
ACCEPT
Summary: Early endosome localization is supported by Rabankyrin-5 colocalization with Rab5/EEA1-positive compartments and later functional studies.
Reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal localization is required for endosomal fusion, retromer-related trafficking, and ATG2A recruitment during autophagy stimulation.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:29959197
GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0005829 cytosol
IEA
GO_REF:0000120
KEEP AS NON CORE
Summary: Cytosol localization is supported as a source pool but is not the main functional location.
Reason: ANKFY1 occurs in soluble and membrane-associated fractions; the reviewed functional evidence points to membrane recruitment at PI3P/Rab5-positive endosomes.
Supporting Evidence:
PMID:10940552
present in both membrane and soluble fractions obtained on subcellular fractionation
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
GO:0010008 endosome membrane
IEA
GO_REF:0000120
ACCEPT
Summary: Endosome membrane localization/activity is well supported for ANKFY1/Rabankyrin-5.
Reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes on early/endosomal membranes; this location is central to its endosomal trafficking and ATG2A-bridging roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0016020 membrane
IEA
GO_REF:0000117
KEEP AS NON CORE
Summary: Generic membrane localization is supported but too broad to represent the core location.
Reason: Membrane association is real, but the more informative annotation is endosome membrane/early endosome, where ANKFY1 binds PI3P and functions with Rab5 and ATG2A.
Supporting Evidence:
PMID:10940552
present in both membrane and soluble fractions obtained on subcellular fractionation
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0046872 metal ion binding
IEA
GO_REF:0000002
MODIFY
Summary: Metal ion binding is a broad domain-derived proxy for the FYVE zinc finger and should be replaced by the directly demonstrated lipid-binding activity.
Reason: The FYVE domain is biologically important because it binds PI3P-containing membranes; direct lipid-binding experiments support phosphatidylinositol phosphate binding, while generic metal ion binding is not informative for ANKFY1 function.
Supporting Evidence:
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
enhanced ATG2A-mediated lipid transfer between PI3P-containing liposomes
GO:0005515 protein binding
IPI
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
MODIFY
Summary: The generic protein-binding row reflects Rab5 interaction and should be replaced by small GTPase binding.
Reason: The publication demonstrates specific, direct, GTP-dependent Rab5 binding; GO:0031267 captures the molecular function better than generic protein binding.
Proposed replacements: small GTPase binding
Supporting Evidence:
PMID:15328530
Rabankyrin-5 binds to Rab5 specifically, directly, and GTP dependently
GO:0005515 protein binding
IPI
PMID:20562859
Network organization of the human autophagy system.
MODIFY
Summary: The generic protein-binding row reflects ATG8/GABARAP-family association in a high-throughput autophagy network.
Reason: The evidence is a proteomic autophagy-network interaction, so the more specific molecular-function replacement is ubiquitin-like protein binding; it should be treated as non-core relative to Rab5/PI3P/endosomal trafficking.
Proposed replacements: ubiquitin-like protein binding
Supporting Evidence:
PMID:20562859
The six ATG8 orthologues in humans (MAP1LC3/GABARAP proteins) interact with a cohort of 67 proteins
PMID:20562859
FYVE domain-containing proteins FYCO1 and ANKFY1
GO:0005515 protein binding
IPI
PMID:22284051
Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endoc...
MODIFY
Summary: The generic protein-binding row reflects Rank-5 binding to the EHD1 EH domain.
Reason: Rank-5 contains an NPFED motif that binds the EHD1 EH domain; GO:1990175 EH domain binding captures this interaction better than generic protein binding.
Proposed replacements: EH domain binding
Supporting Evidence:
PMID:22284051
binding occurs between the EH domain of EHD1 and the NPFED motif of Rank-5
GO:0005515 protein binding
IPI
PMID:27189942
EHD3 Protein Is Required for Tubular Recycling Endosome Stab...
UNDECIDED
Summary: The local cached article does not provide ANKFY1-specific text for this generic EHD1/Q9H4M9 interaction row.
Reason: The abstract supports EHD paralog binding to NPF-containing partners generally, but the cached text available locally does not document the ANKFY1/Rabankyrin-5 interaction with EHD1 specifically. A replacement such as EH domain binding may be appropriate if full interaction evidence is checked, but this row should remain undecided until the specific evidence is accessible.
Supporting Evidence:
PMID:27189942
EHD proteins have an EH domain that interacts with proteins containing an NPF motif
PMID:22284051
binding occurs between the EH domain of EHD1 and the NPFED motif of Rank-5
GO:0005515 protein binding
IPI
PMID:27189942
EHD3 Protein Is Required for Tubular Recycling Endosome Stab...
UNDECIDED
Summary: The local cached article does not provide ANKFY1-specific text for this generic EHD3/Q9NZN3 interaction row.
Reason: The GOA includes a distinct PMID:27189942 IPI row for EHD3/Q9NZN3. The cached abstract supports EHD-family EH-domain recognition of NPF-containing partners and distinguishes EHD1 from EHD3, but it does not expose ANKFY1/Rabankyrin-5-specific interaction evidence for this partner. This row should remain undecided until the specific IntAct/full-text evidence is accessible.
Supporting Evidence:
PMID:27189942
EHD proteins have an EH domain that interacts with proteins containing an NPF motif
PMID:27189942
EHD1 and EHD3 have 86% amino acid identity; they homo- and heterodimerize and partially co-localize to TRE
GO:0005768 endosome
IDA
GO_REF:0000052
ACCEPT
Summary: Endosome localization is supported and relevant to ANKFY1 function.
Reason: The original ANKHZN paper and later Rabankyrin-5 studies place the protein on endosomes, where it binds Rab5/PI3P and coordinates endocytic trafficking.
Supporting Evidence:
PMID:10940552
Ankhzn protein is ubiquitously expressed in a spatiotemporal-specific manner and is located on endosomes
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
GO:0005737 cytoplasm
EXP
PMID:10940552
Characterization and chromosomal mapping of a novel human ge...
KEEP AS NON CORE
Summary: Cytoplasmic localization is supported but is less informative than endosome-membrane localization.
Reason: ANKFY1 was initially described as a cytoplasmic protein and is present in soluble fractions, but the biologically informative location is its recruitment to PI3P/Rab5-positive endosomal membranes.
Supporting Evidence:
PMID:10940552
Ankhzn protein is ubiquitously expressed in a spatiotemporal-specific manner and is located on endosomes
PMID:10940552
present in both membrane and soluble fractions obtained on subcellular fractionation
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
GO:0005769 early endosome
EXP
PMID:22284051
Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endoc...
ACCEPT
Summary: Early endosome localization is supported by Rabankyrin-5 colocalization with Rab5/EEA1-positive compartments and later functional studies.
Reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal localization is required for endosomal fusion, retromer-related trafficking, and ATG2A recruitment during autophagy stimulation.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:29959197
GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0005769 early endosome
EXP
PMID:29959197
GAPVD1 and ANKFY1 Mutations Implicate RAB5 Regulation in Nep...
ACCEPT
Summary: Early endosome localization is supported by Rabankyrin-5 colocalization with Rab5/EEA1-positive compartments and later functional studies.
Reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal localization is required for endosomal fusion, retromer-related trafficking, and ATG2A recruitment during autophagy stimulation.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:29959197
GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0010008 endosome membrane
EXP
PMID:10940552
Characterization and chromosomal mapping of a novel human ge...
ACCEPT
Summary: Endosome membrane localization/activity is well supported for ANKFY1/Rabankyrin-5.
Reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes on early/endosomal membranes; this location is central to its endosomal trafficking and ATG2A-bridging roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0010008 endosome membrane
TAS
Reactome:R-HSA-9013438
ACCEPT
Summary: Endosome membrane localization/activity is well supported for ANKFY1/Rabankyrin-5.
Reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes on early/endosomal membranes; this location is central to its endosomal trafficking and ATG2A-bridging roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0070062 extracellular exosome
HDA
PMID:18570454
Proteomic analysis of exosomes from human neural stem cells ...
KEEP AS NON CORE
Summary: Extracellular exosome detection comes from high-throughput proteomics and is not central to ANKFY1 function.
Reason: The exosome rows may reflect proteomic detection, but they do not explain the core Rab5/PI3P/endosomal trafficking and ATG2A autophagosome-assembly roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:20562859
depletion of ANKFY1 also led to increased autophagosomal number without blocking flux
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0016197 endosomal transport
IMP
PMID:24102721
RhoD binds the Rab5 effector Rabankyrin-5 and has a role in ...
ACCEPT
Summary: Endosomal transport is supported by RhoD/PDGFR trafficking and the broader Rabankyrin-5 endosomal phenotype.
Reason: RhoD and Rabankyrin-5 coordinate Rab/Rho activities during internalization and trafficking of activated receptor cargo; this is consistent with the core endosomal transport function.
Supporting Evidence:
PMID:24102721
coordinating RhoD and Rab activities during internalization and trafficking of activated tyrosine kinase receptors
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:22284051
depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
GO:0030904 retromer complex
IDA
PMID:22284051
Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endoc...
KEEP AS NON CORE
Summary: Retromer complex colocalization is supported, but ANKFY1 is not established as a retromer complex subunit.
Reason: The qualifier is colocalizes_with, and the evidence shows interaction/colocalization with VPS26 and retromer distribution defects rather than stable retromer-complex membership.
Supporting Evidence:
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:22284051
depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
GO:0042147 retrograde transport, endosome to Golgi
IMP
PMID:22284051
Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endoc...
ACCEPT
Summary: Endosome-to-Golgi retrograde transport is supported by Rank-5/retromer evidence.
Reason: Rank-5 interacts and colocalizes with retromer cargo-recognition components, and Rank-5 depletion impairs mannose 6-phosphate receptor retrieval from endosomes to the Golgi.
Supporting Evidence:
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:22284051
depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
GO:0090160 Golgi to lysosome transport
IMP
PMID:22284051
Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endoc...
ACCEPT
Summary: Golgi-to-lysosome/biosynthetic transport is supported as part of the Rank-5 retromer-trafficking phenotype.
Reason: The same Rank-5 depletion experiments that disrupt retromer distribution also affect biosynthetic transport, consistent with a role in endosome/Golgi/lysosome trafficking.
Supporting Evidence:
PMID:22284051
depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
GO:0005769 early endosome
IDA
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
ACCEPT
Summary: Early endosome localization is supported by Rabankyrin-5 colocalization with Rab5/EEA1-positive compartments and later functional studies.
Reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal localization is required for endosomal fusion, retromer-related trafficking, and ATG2A recruitment during autophagy stimulation.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:22284051
Rank-5 colocalizes and interacts with components of the retromer complex such as vacuolar protein sorting 26 (Vps26)
PMID:29959197
GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0031267 small GTPase binding
IDA
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
ACCEPT
Summary: Small GTPase binding is directly supported by Rab5 and RhoD/RAB-family interaction evidence.
Reason: Rabankyrin-5 was identified as a GTP-dependent Rab5 effector, and additional disease/trafficking work supports interaction with RAB5-regulatory machinery; this is a core molecular function.
Supporting Evidence:
PMID:15328530
Rabankyrin-5 binds to Rab5 specifically, directly, and GTP dependently
PMID:24102721
RhoD binds to the Rab5 effector Rabankyrin-5
PMID:29959197
GAPVD1 and ANKFY1 interact with the endosomal regulator RAB5
GO:0034058 endosomal vesicle fusion
IDA
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
ACCEPT
Summary: Endosomal vesicle fusion is directly supported by the original Rabankyrin-5 functional study.
Reason: Rabankyrin-5 is a Rab5/PI3P effector that stimulates early-endosome fusion and affects endosomal vesicle dynamics.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:15328530
Rabankyrin-5 is a Rab5 effector required for the formation of macropinosomes
GO:0044354 macropinosome
IDA
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
ACCEPT
Summary: Macropinosome localization is directly supported and relevant to the pinocytosis phenotype.
Reason: Rabankyrin-5 localizes to macropinosomes and its perturbation changes fluid-phase uptake.
Supporting Evidence:
PMID:15328530
Overexpression of Rabankyrin-5 increases the number of macropinosomes and stimulates fluid-phase uptake, whereas its downregulation inhibits these processes
GO:0048549 positive regulation of pinocytosis
IDA
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
ACCEPT
Summary: Positive regulation of pinocytosis is directly supported.
Reason: Overexpression and depletion experiments show that Rabankyrin-5 promotes fluid-phase/macropinocytic uptake, including apical non-clathrin-mediated uptake in polarized cells.
Supporting Evidence:
PMID:15328530
Overexpression of Rabankyrin-5 increases the number of macropinosomes and stimulates fluid-phase uptake, whereas its downregulation inhibits these processes
PMID:15328530
specifically stimulates apical, non-clathrin-mediated fluid-phase endocytosis
GO:1901981 phosphatidylinositol phosphate binding
IDA
PMID:15328530
The Rab5 effector Rabankyrin-5 regulates and coordinates dif...
ACCEPT
Summary: Phosphatidylinositol phosphate binding is a core ANKFY1 molecular function.
Reason: ANKFY1/Rabankyrin-5 binds PI3P via its FYVE domain; this lipid-binding activity explains endosomal recruitment and is required for ATG2A-mediated lipid-transfer enhancement.
Supporting Evidence:
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
enhanced ATG2A-mediated lipid transfer between PI3P-containing liposomes
GO:0070062 extracellular exosome
HDA
PMID:19056867
Large-scale proteomics and phosphoproteomics of urinary exos...
KEEP AS NON CORE
Summary: Extracellular exosome detection comes from high-throughput proteomics and is not central to ANKFY1 function.
Reason: The exosome rows may reflect proteomic detection, but they do not explain the core Rab5/PI3P/endosomal trafficking and ATG2A autophagosome-assembly roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:20562859
depletion of ANKFY1 also led to increased autophagosomal number without blocking flux
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0005765 lysosomal membrane
HDA
PMID:17897319
Integral and associated lysosomal membrane proteins.
KEEP AS NON CORE
Summary: Lysosomal membrane detection is plausible but high-throughput and not core.
Reason: The dominant evidence places ANKFY1 on early/endosomal membranes; lysosomal-membrane proteomic detection is peripheral and should not drive the core function summary.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0016020 membrane
IDA
PMID:10940552
Characterization and chromosomal mapping of a novel human ge...
KEEP AS NON CORE
Summary: Generic membrane localization is supported but too broad to represent the core location.
Reason: Membrane association is real, but the more informative annotation is endosome membrane/early endosome, where ANKFY1 binds PI3P and functions with Rab5 and ATG2A.
Supporting Evidence:
PMID:10940552
present in both membrane and soluble fractions obtained on subcellular fractionation
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0010008 endosome membrane
ISS
GO_REF:0000024
ACCEPT
Summary: Endosome membrane localization/activity is well supported for ANKFY1/Rabankyrin-5.
Reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes on early/endosomal membranes; this location is central to its endosomal trafficking and ATG2A-bridging roles.
Supporting Evidence:
PMID:15328530
novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity
PMID:15328530
Rabankyrin-5 binds most strongly to PI(3)P
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
GO:0000045 autophagosome assembly
IMP
PMID:38622126
ANKFY1 bridges ATG2A-mediated lipid transfer from endosomes ...
NEW
Summary: ANKFY1 should be added to autophagosome assembly for its ATG2A-dependent endosome-to-phagophore lipid-transfer role.
Reason: ANKFY1 depletion impairs autophagosome growth, reduces autophagy flux, and phenocopies ATG2A/B depletion; in vitro ANKFY1 enhances ATG2A-mediated lipid transfer between PI3P-containing membranes. GO:0000045 is the conservative process term for this phagophore-growth/autophagosome-completion role.
Supporting Evidence:
PMID:38622126
identified a new ATG2A-binding protein, ANKFY1
PMID:38622126
Depletion of this endosome-localized protein led to the impaired autophagosome growth and the reduced autophagy flux
PMID:38622126
enhanced ATG2A-mediated lipid transfer between PI3P-containing liposomes
PMID:38622126
ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
file:human/ANKFY1/ANKFY1-deep-research-falcon.md
A 2024 study identified ANKFY1 as an ATG2A-binding endosomal factor that bridges endosomes and phagophores, promoting ATG2A-mediated lipid transfer for phagophore growth

Core Functions

ANKFY1 is a Rab5/PI3P-positive endosomal effector that coordinates early endosome fusion, macropinocytosis, endosomal transport, and retromer-associated endosome-to-Golgi and Golgi-to-lysosome trafficking.

Supporting Evidence:
  • PMID:15328530
    Rabankyrin-5 binds to Rab5 specifically, directly, and GTP dependently
  • PMID:15328530
    Rabankyrin-5 binds most strongly to PI(3)P
  • PMID:15328530
    Overexpression of Rabankyrin-5 increases the number of macropinosomes and stimulates fluid-phase uptake, whereas its downregulation inhibits these processes
  • PMID:22284051
    depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport
  • PMID:24102721
    coordinating RhoD and Rab activities during internalization and trafficking of activated tyrosine kinase receptors

ANKFY1 binds PI3P-rich endosomal membranes through its FYVE domain and promotes ATG2A-mediated lipid transfer from endosomes to phagophores, supporting autophagosome growth and completion during autophagy induction.

Supporting Evidence:
  • PMID:38622126
    identified a new ATG2A-binding protein, ANKFY1
  • PMID:38622126
    Depletion of this endosome-localized protein led to the impaired autophagosome growth and the reduced autophagy flux
  • PMID:38622126
    enhanced ATG2A-mediated lipid transfer between PI3P-containing liposomes
  • PMID:38622126
    ANKFY1 recruits ATG2A to PI3P-enriched endosomes and promotes ATG2A-mediated lipid transfer from endosomes to phagophores
  • file:human/ANKFY1/ANKFY1-notes.md
    ANKFY1 also has direct autophagy-relevant evidence

References

Gene Ontology annotation through association of InterPro records with GO terms
Manual transfer of experimentally-verified manual GO annotation data to orthologs by curator judgment of sequence similarity
Annotation inferences using phylogenetic trees
Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular Location vocabulary mapping, accompanied by conservative changes to GO terms applied by UniProt
Gene Ontology annotation based on curation of immunofluorescence data
Electronic Gene Ontology annotations created by ARBA machine learning models
Combined Automated Annotation using Multiple IEA Methods
Characterization and chromosomal mapping of a novel human gene, ANKHZN.
The Rab5 effector Rabankyrin-5 regulates and coordinates different endocytic mechanisms.
Integral and associated lysosomal membrane proteins.
Proteomic analysis of exosomes from human neural stem cells by flow field-flow fractionation and nanoflow liquid chromatography-tandem mass spectrometry.
Large-scale proteomics and phosphoproteomics of urinary exosomes.
Network organization of the human autophagy system.
Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endocytic trafficking and retromer function.
RhoD binds the Rab5 effector Rabankyrin-5 and has a role in trafficking of the platelet-derived growth factor receptor.
EHD3 Protein Is Required for Tubular Recycling Endosome Stabilization, and an Asparagine-Glutamic Acid Residue Pair within Its Eps15 Homology (EH) Domain Dictates Its Selective Binding to NPF Peptides.
GAPVD1 and ANKFY1 Mutations Implicate RAB5 Regulation in Nephrotic Syndrome.
Reactome:R-HSA-9013438
RHOD binds effectors at the endosome membrane
ANKFY1 bridges ATG2A-mediated lipid transfer from endosomes to phagophores.
  • ANKFY1 binds ATG2A during autophagy stimulation and promotes ATG2A-mediated lipid transfer from endosomes to phagophores.
  • ANKFY1 depletion impairs autophagosome growth and reduces autophagy flux.
file:human/ANKFY1/ANKFY1-uniprot.txt
UniProtKB record for human ANKFY1/Rabankyrin-5
  • UniProt summarizes ANKFY1 as a Rab5 effector involved in endosomal trafficking, macropinocytosis, receptor internalization, retromer-mediated transport, and podocyte migration.
file:human/ANKFY1/ANKFY1-notes.md
ANKFY1 review notes for Proteostasis PN assessment
  • The PN Cul3 substrate-receptor projection to GO:1990756 is not supported by ANKFY1-specific evidence.
  • ANKFY1 is proteostasis-relevant through endosome-autophagosome lipid transfer rather than validated ubiquitin-like ligase-substrate adaptor activity.
file:human/ANKFY1/ANKFY1-deep-research-falcon.md
Falcon deep research report for human ANKFY1
  • The Falcon report summarizes ANKFY1 as a Rab5/PI3P endosomal scaffold with recent ATG2A-mediated autophagy evidence.
projects/PROTEOSTASIS/reports/pn_projection/pn_projected_annotations.tsv
Proteostasis PN projected annotations report
  • The report projects GO:1990756 to ANKFY1 from the Cul3 substrate receptor PN group.

Suggested Questions for Experts

Q: Is there direct experimental evidence that ANKFY1 binds CUL3 or functions as a CRL3/ubiquitin-like ligase substrate adaptor in cells?

Suggested experts: GO ubiquitin-proteasome curators, Proteostasis PN curators

Q: Should ANKFY1 autophagy annotation be limited to autophagosome assembly, or should a more specific future term capture endosome-to-phagophore lipid-transfer bridging by ATG2A adaptors?

Suggested experts: GO autophagy editors

Suggested Experiments

Experiment: Test endogenous ANKFY1-CUL3 binding by reciprocal co-immunoprecipitation or proximity labeling, identify candidate substrates, and determine whether ANKFY1 loss changes CUL3-dependent ubiquitination of those substrates.

Hypothesis: ANKFY1 does not function as a CRL3 substrate receptor unless it shows endogenous CUL3 complex membership and substrate-dependent ubiquitination activity.

Type: Endogenous CUL3 complex and ubiquitination assay

Experiment: Rescue ANKFY1 knockout cells with wild-type, FYVE-deleted, and ATG2A-binding-defective ANKFY1 variants, then assay Halo-LC3 autophagosome completion, LC3 flux, WIPI2/LC3 phagophore PI3P, and in vitro ATG2A lipid transfer.

Hypothesis: FYVE-dependent endosomal recruitment and ATG2A binding are required for ANKFY1 support of phagophore growth.

Type: ANKFY1 autophagy rescue assay

Deep Research

Falcon

(ANKFY1-deep-research-falcon.md)
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate. Falcon Edison Scientific Literature 18 citations 2 artifacts 2026-06-03T12:00:16.731108

The research report should be a detailed narrative explaining the function, biological processes, and localization of the gene product. Citations should be given for all claims.

You should prioritize authoritative reviews and primary scientific literature when conducting research. You can supplement
this with annotations you find in gene/protein databases, but these can be outdated or inaccurate.

We are specifically interested in the primary function of the gene - for enzymes, what reaction is catalyzed, and what is the substrate specificity? For transporters, what is the substrate? For structural proteins or adapters, what is the broader structural role? For signaling molecules, what is the role in the pathway.

We are interested in where in or outside the cell the gene product carries out its function.

We are also interested in the signaling or biochemical pathways in which the gene functions. We are less interested in broad pleiotropic effects, except where these elucidate the precise role.

Include evidence where possible. We are interested in both experimental evidence as well as inference from structure, evolution, or bioinformatic analysis. Precise studies should be prioritized over high-throughput, where available.

Research report: Human ANKFY1 (Rabankyrinโ€‘5; UniProt Q9P2R3)โ€”functional annotation, mechanisms, and recent research

0) Target verification (gene/protein identity)

The literature consistently identifies ANKFY1 (human) as Rabankyrinโ€‘5, a Rab5 effector protein that contains an Nโ€‘terminal BTB/POZ domain, extensive ankyrin repeats, and a Cโ€‘terminal FYVE domain, matching the UniProt Q9P2R3 description you provided. The canonical 2004 discovery paper explicitly defines this protein architecture and Rab5/PI3P binding properties, and later human genetic/functional work in podocytes uses the same ANKFY1 identity and FYVEโ€‘dependent vesicular targeting (schnatwinkel2004therab5effector pages 2-3, hermle2018gapvd1andankfy1 pages 4-7).

1) Key concepts and definitions (current understanding)

1.1 ANKFY1 as a Rab5 effector

A Rab5 effector is a protein that binds activated Rab5โ€‘GTP to execute Rab5โ€‘dependent functions on early endosomes (e.g., tethering, fusion, trafficking coordination). Rabankyrinโ€‘5/ANKFY1 binds Rab5 specifically and in a GTPโ€‘dependent manner, i.e., it binds Rab5โ€‘GTP analogs but not Rab5โ€‘GDP and not other tested Rab proteins, satisfying a biochemical definition of a Rab5 effector (Schnatwinkel et al., 2004โ€‘08; https://doi.org/10.1371/journal.pbio.0020261) (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004therab5effector pages 1-2).

1.2 FYVE domain and PI(3)P recognition

The FYVE domain is a zincโ€‘finger fold that typically binds phosphatidylinositolโ€‘3โ€‘phosphate (PI3P), a hallmark lipid enriched on early endosomes. ANKFY1 is directly PI3Pโ€‘binding, as shown by liposome binding assays, and FYVEโ€‘mediated PI3P recognition is a key determinant of its membrane recruitment (Schnatwinkel et al., 2004โ€‘08; https://doi.org/10.1371/journal.pbio.0020261) (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 106-107).

1.3 Ankyrin repeats and BTB/POZ domain (conceptual roles)

Ankyrin repeats are common proteinโ€“protein interaction modules and are frequently used to scaffold multiโ€‘protein assemblies. In the discovery work, ANKFY1/Rabankyrinโ€‘5 is described as containing ~21 ankyrin repeats and an Nโ€‘terminal BTB/POZ region, consistent with a role as an endocytic scaffold rather than an enzyme (Schnatwinkel et al., 2004โ€‘08; https://doi.org/10.1371/journal.pbio.0020261) (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 101-104).

2) Molecular function, pathways, and subcellular localization

2.1 Subcellular localization: early endosomes and macropinosomes

ANKFY1 localizes predominantly to Rab5/EEA1โ€‘positive early endosomes and also to large vacuolar structures corresponding to macropinosomes (Schnatwinkel et al., 2004โ€‘08; https://doi.org/10.1371/journal.pbio.0020261) (schnatwinkel2004therab5effector pages 1-2, schnatwinkel2004therab5effector pages 10-12, schnatwinkel2004therab5effector pages 2-3). Quantitatively, the early endosome coโ€‘localization with Rab5/EEA1 was reported at approximately ~80% in A431 cells (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 104-106).

2.2 Core cellular roles: coordinating endocytosis/macropinocytosis and endosome fusion

Macropinocytosis / fluidโ€‘phase uptake. In epithelial cells and fibroblasts, overexpression of Rabankyrinโ€‘5 increased macropinosome number and stimulated fluidโ€‘phase uptake, while downregulation inhibited these processes. In polarized epithelia, this activity was largely apical (Schnatwinkel et al., 2004โ€‘08; https://doi.org/10.1371/journal.pbio.0020261) (schnatwinkel2004therab5effector pages 1-2, schnatwinkel2004therab5effector pages 10-12).

Endosome fusion. Rabankyrinโ€‘5/ANKFY1 stimulates early endosome fusion activity and can influence fusion steps involving clathrinโ€‘derived cargo delivery to early endosomes; however, complementary characterization indicates a modulatory contribution in certain fusion assays (not the sole essential component) (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 104-106).

2.3 Determinants of endosomal targeting: requirement for both PI3P and Rab5

A key mechanistic point is that ANKFY1 targeting to early endosomes depends on both (i) FYVEโ€‘mediated PI3P binding and (ii) Rab5 interaction. A FYVEโ€‘deleted ANKFY1 can still bind Rab5โ€‘GTP in vitro but fails to localize properly in vivo, and recruitment assays show dependence on Rab5 and PI3P together (schnatwinkel2004characterisationofnovel pages 106-107, schnatwinkel2004characterisationofnovel pages 104-106).

3) Recent developments (prioritizing 2023โ€“2024)

3.1 2024: ANKFY1 in autophagyโ€”bridging endosomes to phagophores via ATG2A

A major 2024 advance is the identification of ANKFY1 as a new ATG2Aโ€‘binding factor that links PI3Pโ€‘enriched endosomes to phagophores during autophagosome biogenesis (Wei et al., 2024โ€‘04, Cell Discovery; https://doi.org/10.1038/s41421-024-00659-y) (wei2024ankfy1bridgesatg2amediated pages 1-2, wei2024ankfy1bridgesatg2amediated pages 2-4).

Mechanistic findings:
- Physical/functional coupling: tandem affinity purification + MS identified ANKFY1 as an ATG2A interactor, validated by coโ€‘IP; binding increased under autophagy stimulation conditions (e.g., Torin1/starvation) (wei2024ankfy1bridgesatg2amediated pages 1-2).
- PI3P dependence: recombinant ANKFY1 binds PI3P strongly, and FYVE deletion abrogates its capacity to support ATG2A activity (wei2024ankfy1bridgesatg2amediated pages 2-4, wei2024ankfy1bridgesatg2amediated pages 10-12).
- Reconstitution: In liposome assays, ANKFY1 robustly recruited ATG2A to PI3P membranes and promoted tethering/clustering, enabling enhanced ATG2A lipid transfer (wei2024ankfy1bridgesatg2amediated pages 2-4, wei2024ankfy1bridgesatg2amediated pages 8-10).
- Quantitative effect size: ANKFY1 approximately doubled ATG2A lipid transfer efficiency in a FRETโ€‘based lipid transfer assay (wei2024ankfy1bridgesatg2amediated pages 10-12).

The most direct visual evidence is provided by microscopy showing ANKFY1 in close proximity to both endosomal and phagophore markers and by biochemistry/biophysics panels showing enhanced ATG2A recruitment and lipid transfer (wei2024ankfy1bridgesatg2amediated media a99a411e, wei2024ankfy1bridgesatg2amediated media ea7133fe).

3.2 2024: Human geneticsโ€”biโ€‘allelic ANKFY1 variants and a proposed neuroโ€‘renal phenotype

A 2024 case report describes a child with infantileโ€‘onset proteinuria and a movement disorder carrying compound heterozygous ANKFY1 variants (Zhang et al., 2024โ€‘06, Clinical Kidney Journal; https://doi.org/10.1093/ckj/sfae124) (zhang2024compoundheterozygousvariants pages 1-3).

Notable functional and quantitative observations in this report:
- An intronic deletion caused abnormal splicing with nested PCR products of 199 bp (full length) and 108 bp (exonโ€‘24 skipped) (zhang2024compoundheterozygousvariants pages 3-4).
- Both variants reduced ANKFY1 protein expression in transfected cells; localization was not obviously altered in that overexpression assay (zhang2024compoundheterozygousvariants pages 4-5).
- Reported urinary microprotein values included ฮฑ1โ€‘microglobulin 127 mg/L, microalbumin 159 mg/L, and IgG 42.3 mg/L (zhang2024compoundheterozygousvariants pages 1-3).

These findings complement earlier evidence linking ANKFY1 to steroidโ€‘resistant nephrotic syndrome via Rab5/endocytic regulation (see ยง4.2) (hermle2018gapvd1andankfy1 pages 4-7).

4) Current applications and realโ€‘world implementations

4.1 ANKFY1 as a mechanistic node in membrane trafficking research (cell biology application)

In practice, ANKFY1 is used as:
- a marker and mechanistic component for Rab5/PI3P early endosome biology and macropinocytosis studies, due to its Rab5โ€‘GTP and PI3P binding and its localization to early endosomes/macropinosomes (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004therab5effector pages 10-12);
- an experimentally tractable scaffold to dissect how endosomes and PI3Pโ€‘positive membranes coordinate diverse uptake routes (clathrinโ€‘dependent and macropinocytic) under Rab5 control (schnatwinkel2004therab5effector pages 10-12, schnatwinkel2004therab5effector pages 1-2).

4.2 Clinical genetics implementation (SRNS diagnostics)

Wholeโ€‘exome sequencing in a cohort of 665 patients with steroidโ€‘resistant nephrotic syndrome identified a homozygous ANKFY1 variant in two siblings, and functional assays supported a Rab5 regulatory mechanism through ANKFY1 and GAPVD1 interaction (Hermle et al., 2018โ€‘06, JASN; https://doi.org/10.1681/ASN.2017121312) (hermle2018gapvd1andankfy1 pages 4-7). This positions ANKFY1 as a gene that can be included in monogenic SRNS diagnostic evaluation and mechanistic interpretation, particularly in cases suggesting endocytic trafficking defects.

5) Expert opinions and synthesis (authoritative analysis grounded in sources)

5.1 ANKFY1 is best viewed as a PI3P/Rab5โ€‘dependent endosomal scaffold rather than an enzyme

Across biochemical binding assays, localization, and functional perturbations, the most consistent interpretation is that ANKFY1 is an adapter/scaffold that couples Rab5โ€‘GTP signaling to PI3Pโ€‘rich membranes, influencing endosome fusion dynamics and macropinocytic uptake (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004therab5effector pages 1-2). Its requirement for both Rab5 interaction and PI3P binding for correct targeting supports a โ€œcoincidence detectionโ€ model commonly invoked for endosomal effectors (schnatwinkel2004characterisationofnovel pages 106-107, schnatwinkel2004characterisationofnovel pages 104-106).

5.2 A 2024 expansion of scope: from endocytosis to autophagosome growth

Wei et al. (2024) extend the ANKFY1 functional landscape by proposing that PI3Pโ€‘endosomes are not only trafficking hubs but can serve as lipid donors to growing phagophores via an ANKFY1โ†’ATG2A bridging mechanism (wei2024ankfy1bridgesatg2amediated pages 1-2, wei2024ankfy1bridgesatg2amediated pages 2-4). The combined inโ€‘cell and inโ€‘vitro reconstitution evidence, including a quantitative increase in lipid transfer efficiency, supports an actionable mechanistic model rather than a purely correlative association (wei2024ankfy1bridgesatg2amediated pages 10-12, wei2024ankfy1bridgesatg2amediated media ea7133fe).

6) Relevant statistics and data highlights (from cited studies)

  • ~80% colocalization of endogenous ANKFY1 with Rab5/EEA1 early endosome markers in A431 cells (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 104-106).
  • Cohort size: 665 SRNS patients screened by exome sequencing in Hermle et al. 2018 (hermle2018gapvd1andankfy1 pages 4-7).
  • Autophagy reconstitution: PI3P liposomes used at 5% PI3P; ANKFY1 enhanced ATG2A recruitment and lipid transfer; reported to ~double ATG2A lipid transfer efficiency in FRET assays (wei2024ankfy1bridgesatg2amediated pages 2-4, wei2024ankfy1bridgesatg2amediated pages 10-12).
  • Clinical splicing assay: 199 bp full-length vs 108 bp exonโ€‘24โ€‘skipped products in a nested PCR assay for an ANKFY1 intronic deletion (zhang2024compoundheterozygousvariants pages 3-4).
  • Clinical urine markers: ฮฑ1โ€‘microglobulin 127 mg/L, microalbumin 159 mg/L, IgG 42.3 mg/L in the 2024 neuroโ€‘renal phenotype report (zhang2024compoundheterozygousvariants pages 1-3).

7) Disease associations (curated evidence)

Open Targets lists ANKFY1 association signals for familial idiopathic steroidโ€‘resistant nephrotic syndrome, neurodegenerative disease, type 2 diabetes mellitus, obesity, and overnutrition, each with evidence size 3; the displayed association scores include ~0.37 for familial idiopathic SRNS and ~0.33 for neurodegenerative disease (platform: https://platform.opentargets.org/) (OpenTargets Search: -ANKFY1). These associations should be interpreted as aggregation of evidence types (e.g., genetics/functional/omics) rather than proof of direct causality or druggability.

8) Summary of functional annotation

ANKFY1 (Rabankyrinโ€‘5) is a PI3Pโ€‘binding, Rab5โ€‘GTPโ€‘binding endosomal scaffold that localizes to early endosomes and macropinosomes, promotes macropinocytic fluidโ€‘phase uptake, and modulates endosome fusion. Recent 2024 work extends ANKFY1โ€™s role to autophagy, where it recruits/bridges ATG2A to PI3P endosomes to enhance lipid transfer and phagophore expansion. Human genetics implicate ANKFY1 in steroidโ€‘resistant nephrotic syndrome, and a 2024 case report suggests a possible broader neuroโ€‘renal syndrome associated with biโ€‘allelic ANKFY1 variants (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004therab5effector pages 10-12, wei2024ankfy1bridgesatg2amediated pages 1-2, hermle2018gapvd1andankfy1 pages 4-7, zhang2024compoundheterozygousvariants pages 1-3).


Structured evidence table

Aspect Key claim Evidence type Key quantitative/statistical details Primary source with publication date and URL/DOI Citation id(s) to use in final answer
Identity/domains Human ANKFY1 corresponds to Rabankyrin-5, a Rab5 effector with an N-terminal BTB/POZ domain, ~21 ankyrin repeats, and a C-terminal FYVE finger/domain. Biochemical, cell biology Predicted size ~130 kDa; truncation mapping used constructs spanning aa 1โ€“1169, 1โ€“1075, 255โ€“1169, 255โ€“1075. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 101-104, schnatwinkel2004characterisationofnovel pages 104-106)
Lipid binding ANKFY1 directly binds phosphatidylinositol 3-phosphate [PI(3)P], and FYVE-mediated PI(3)P recognition is required for membrane targeting. Biochemical Liposome-binding assays showed strongest binding to PI(3)P; FYVE deletion abolished endosomal recruitment despite retained Rab5-GTP binding in vitro. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 106-107, schnatwinkel2004characterisationofnovel pages 104-106)
Rab5 binding ANKFY1 binds Rab5 specifically, directly, and in a GTP-dependent manner, consistent with its designation as a Rab5 effector. Biochemical Binds GST-Rab5-GTPฮณS/GTPcS, not Rab5-GDP or other tested Rabs. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 101-104, schnatwinkel2004therab5effector pages 1-2)
Localization ANKFY1 localizes to Rab5/EEA1-positive early endosomes and to large vacuolar macropinosomes; in kidney it is enriched beneath the apical brush border of proximal tubule cells. Cell biology ~80% colocalization with Rab5/EEA1-positive early endosomes in A431 cells; macropinocytic structures are largely transferrin-negative. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004therab5effector pages 10-12, schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 104-106, schnatwinkel2004therab5effector pages 1-2)
Endocytosis/macropinocytosis ANKFY1 promotes fluid-phase uptake and macropinocytosis, especially at the apical membrane of polarized epithelial cells. Overexpression increases, and depletion reduces, macropinosome formation/uptake. Cell biology Overexpression increased macropinosome number and fluid-phase uptake; downregulation inhibited these processes; apical restriction emphasized in polarized epithelia. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004therab5effector pages 10-12, schnatwinkel2004therab5effector pages 1-2, schnatwinkel2004characterisationofnovel pages 134-138)
Endosome fusion ANKFY1 modulates early endosome fusion, stimulating homotypic early-endosome fusion and heterotypic fusion with clathrin-coated vesicles, but appears modulatory rather than the sole essential factor. Biochemical, cell biology Quantitative immunodepletion produced only minor effects in some early-endosome fusion assays, supporting a modulatory role. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004therab5effector pages 2-3, schnatwinkel2004characterisationofnovel pages 106-107, schnatwinkel2004characterisationofnovel pages 104-106)
Domain requirements for targeting Efficient recruitment of ANKFY1 to early endosomes requires both PI(3)P/FYVE recognition and Rab5 interaction; neither module alone is sufficient. Biochemical, cell biology FYVE deletion mutant still bound Rab5-GTP in vitro but failed to localize in vivo; recruitment assays showed dependence on both Rab5 and PI(3)P. Schnatwinkel et al., 2004-08, PLoS Biology; https://doi.org/10.1371/journal.pbio.0020261 (schnatwinkel2004characterisationofnovel pages 104-106, schnatwinkel2004characterisationofnovel pages 106-107)
Autophagy/phagophore expansion A 2024 study identified ANKFY1 as an ATG2A-binding endosomal factor that bridges endosomes and phagophores, promoting ATG2A-mediated lipid transfer for phagophore growth. Biochemical, cell biology ANKFY1 depletion impaired autophagosome growth and autophagy flux, largely phenocopying ATG2A/B depletion. Wei et al., 2024-04, Cell Discovery; https://doi.org/10.1038/s41421-024-00659-y (wei2024ankfy1bridgesatg2amediated pages 1-2, wei2024ankfy1bridgesatg2amediated pages 2-4)
Autophagy quantitative reconstitution In reconstituted liposome assays, ANKFY1 enhanced ATG2A-mediated lipid transfer and tethering of PI(3)P-containing liposomes; FYVE-mediated PI(3)P binding was essential. Biochemical Example donor liposomes: 61% DOPC, 30% POPE, 2% NBD-PE, 2% Rhod-PE, 5% PI3P; acceptor liposomes: 65% DOPC, 30% POPE, 5% PI3P; ANKFY1 roughly doubled ATG2A lipid transfer efficiency; DLS showed clustering/tethering of 100 nm PI(3)P liposomes only with ATG2A+ANKFY1; microscopy quantification used n=36 vs 48 cells in one assay and n=30 cells in others. Wei et al., 2024-04, Cell Discovery; https://doi.org/10.1038/s41421-024-00659-y (wei2024ankfy1bridgesatg2amediated pages 2-4, wei2024ankfy1bridgesatg2amediated pages 10-12, wei2024ankfy1bridgesatg2amediated pages 8-10, wei2024ankfy1bridgesatg2amediated media a99a411e)
Visual/mechanistic support Figure-level evidence shows ANKFY1-ATG2A proximity at Rab5-positive endosomes and LC3-positive phagophores, plus FRET/co-flotation support for ANKFY1-assisted ATG2A lipid transfer. Figure/image evidence Retrieved figures include microscopy with white-arrow-marked three-way proximity and FRET curves/quantification demonstrating enhanced transfer in the presence of ANKFY1. Wei et al., 2024-04, Cell Discovery; https://doi.org/10.1038/s41421-024-00659-y (wei2024ankfy1bridgesatg2amediated media a99a411e, wei2024ankfy1bridgesatg2amediated media 1181e331, wei2024ankfy1bridgesatg2amediated media ea7133fe, wei2024ankfy1bridgesatg2amediated media 5c7dbd2b)
Kidney/podocyte relevance In podocytes, ANKFY1 localizes to Rab5-positive vesicles/endosomes in a FYVE-dependent manner and interacts with GAPVD1; this supports a role in endocytic regulation relevant to glomerular filtration barrier biology. Cell biology, genetics Deletion of the FYVE domain abrogated vesicular localization; ANKFY1 and GAPVD1 partially colocalized and co-immunoprecipitated; endogenous/overexpressed ANKFY1 partially colocalized with Rab5. Hermle et al., 2018-06, JASN; https://doi.org/10.1681/ASN.2017121312 (hermle2018gapvd1andankfy1 pages 4-7)
Human genetics/disease links Biallelic ANKFY1 variants are linked to steroid-resistant nephrotic syndrome (SRNS), and a 2024 case report extends the phenotype to a probable neuro-renal syndrome with infantile-onset proteinuria plus movement disorder. Human genetics, functional assay 2018 study screened 665 patients by exome sequencing and found homozygous ANKFY1 missense mutation in two siblings with SRNS; 2024 case reported compound heterozygous variants p.Ser918Ter and c.3287โ€“11_3287โ€“10del with abnormal splicing producing 199 bp full-length and 108 bp exon-24-skipped PCR products; urinary markers included ฮฑ1-microglobulin 127 mg/L, microalbumin 159 mg/L, IgG 42.3 mg/L. Hermle et al., 2018-06, JASN; https://doi.org/10.1681/ASN.2017121312; Zhang et al., 2024-06, Clinical Kidney Journal; https://doi.org/10.1093/ckj/sfae124 (hermle2018gapvd1andankfy1 pages 4-7, zhang2024compoundheterozygousvariants pages 4-5, zhang2024compoundheterozygousvariants pages 3-4, zhang2024compoundheterozygousvariants pages 1-3)
Variant functional consequences Patient-derived ANKFY1 variants in the 2024 case reduced ANKFY1 protein expression but did not obviously alter subcellular localization in the overexpression assay. Genetics, cell biology Exon 24-skipped transcript detected; two transcripts differed by ~108 bp; western blot showed reduced ANKFY1 expression from both variants. Zhang et al., 2024-06, Clinical Kidney Journal; https://doi.org/10.1093/ckj/sfae124 (zhang2024compoundheterozygousvariants pages 4-5, zhang2024compoundheterozygousvariants pages 3-4)
Disease-target associations Open Targets currently lists ANKFY1 associations with familial idiopathic SRNS, neurodegenerative disease, type 2 diabetes mellitus, obesity, and overnutrition, but these are association-level signals rather than validated therapeutic indications. Database Evidence size reported as 3 for each listed disease; strongest score among displayed entries was for familial idiopathic SRNS (score 0.3696), followed by neurodegenerative disease (0.3345) and type 2 diabetes mellitus (0.2181). Open Targets platform query for ANKFY1, accessed during this research; https://platform.opentargets.org/ (OpenTargets Search: -ANKFY1)

Table: This table summarizes the main experimentally supported functions, localization, pathways, and disease links for human ANKFY1/Rabankyrin-5. It is designed to provide citable claims and quantitative details for a final research report.

References

  1. (schnatwinkel2004therab5effector pages 2-3): Carsten Schnatwinkel, Savvas Christoforidis, Margaret R Lindsay, Sandrine Uttenweiler-Joseph, Matthias Wilm, Robert G Parton, and Marino Zerial. The rab5 effector rabankyrin-5 regulates and coordinates different endocytic mechanisms. PLoS Biology, 2:e261, Aug 2004. URL: https://doi.org/10.1371/journal.pbio.0020261, doi:10.1371/journal.pbio.0020261. This article has 299 citations and is from a highest quality peer-reviewed journal.

  2. (hermle2018gapvd1andankfy1 pages 4-7): Tobias Hermle, Ronen Schneider, David Schapiro, Daniela A. Braun, Amelie T. van der Ven, Jillian K. Warejko, Ankana Daga, Eugen Widmeier, Makiko Nakayama, Tilman Jobst-Schwan, Amar J. Majmundar, Shazia Ashraf, Jia Rao, Laura S. Finn, Velibor Tasic, Joel D. Hernandez, Arvind Bagga, Sawsan M. Jalalah, Sherif El Desoky, Jameela A. Kari, Kristen M. Laricchia, Monkol Lek, Heidi L. Rehm, Daniel G. MacArthur, Shrikant Mane, Richard P. Lifton, Shirlee Shril, and Friedhelm Hildebrandt. Gapvd1 and ankfy1 mutations implicate rab5 regulation in nephrotic syndrome. Journal of the American Society of Nephrology : JASN, 29 8:2123-2138, Jun 2018. URL: https://doi.org/10.1681/asn.2017121312, doi:10.1681/asn.2017121312. This article has 75 citations.

  3. (schnatwinkel2004therab5effector pages 1-2): Carsten Schnatwinkel, Savvas Christoforidis, Margaret R Lindsay, Sandrine Uttenweiler-Joseph, Matthias Wilm, Robert G Parton, and Marino Zerial. The rab5 effector rabankyrin-5 regulates and coordinates different endocytic mechanisms. PLoS Biology, 2:e261, Aug 2004. URL: https://doi.org/10.1371/journal.pbio.0020261, doi:10.1371/journal.pbio.0020261. This article has 299 citations and is from a highest quality peer-reviewed journal.

  4. (schnatwinkel2004characterisationofnovel pages 106-107): C Schnatwinkel. Characterisation of novel rab5 effector proteins in the endocytic pathway. Unknown journal, 2004.

  5. (schnatwinkel2004characterisationofnovel pages 101-104): C Schnatwinkel. Characterisation of novel rab5 effector proteins in the endocytic pathway. Unknown journal, 2004.

  6. (schnatwinkel2004therab5effector pages 10-12): Carsten Schnatwinkel, Savvas Christoforidis, Margaret R Lindsay, Sandrine Uttenweiler-Joseph, Matthias Wilm, Robert G Parton, and Marino Zerial. The rab5 effector rabankyrin-5 regulates and coordinates different endocytic mechanisms. PLoS Biology, 2:e261, Aug 2004. URL: https://doi.org/10.1371/journal.pbio.0020261, doi:10.1371/journal.pbio.0020261. This article has 299 citations and is from a highest quality peer-reviewed journal.

  7. (schnatwinkel2004characterisationofnovel pages 104-106): C Schnatwinkel. Characterisation of novel rab5 effector proteins in the endocytic pathway. Unknown journal, 2004.

  8. (wei2024ankfy1bridgesatg2amediated pages 1-2): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  9. (wei2024ankfy1bridgesatg2amediated pages 2-4): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  10. (wei2024ankfy1bridgesatg2amediated pages 10-12): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  11. (wei2024ankfy1bridgesatg2amediated pages 8-10): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  12. (wei2024ankfy1bridgesatg2amediated media a99a411e): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  13. (wei2024ankfy1bridgesatg2amediated media ea7133fe): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  14. (zhang2024compoundheterozygousvariants pages 1-3): Luyan Zhang, Xueqin Cheng, Chunli Wang, Wei Zhou, Bixia Zheng, and Aihua Zhang. Compound heterozygous variants of ankfy1 in a child with infantile-onset proteinuria and movement disorder. Clinical Kidney Journal, Jun 2024. URL: https://doi.org/10.1093/ckj/sfae124, doi:10.1093/ckj/sfae124. This article has 0 citations and is from a peer-reviewed journal.

  15. (zhang2024compoundheterozygousvariants pages 3-4): Luyan Zhang, Xueqin Cheng, Chunli Wang, Wei Zhou, Bixia Zheng, and Aihua Zhang. Compound heterozygous variants of ankfy1 in a child with infantile-onset proteinuria and movement disorder. Clinical Kidney Journal, Jun 2024. URL: https://doi.org/10.1093/ckj/sfae124, doi:10.1093/ckj/sfae124. This article has 0 citations and is from a peer-reviewed journal.

  16. (zhang2024compoundheterozygousvariants pages 4-5): Luyan Zhang, Xueqin Cheng, Chunli Wang, Wei Zhou, Bixia Zheng, and Aihua Zhang. Compound heterozygous variants of ankfy1 in a child with infantile-onset proteinuria and movement disorder. Clinical Kidney Journal, Jun 2024. URL: https://doi.org/10.1093/ckj/sfae124, doi:10.1093/ckj/sfae124. This article has 0 citations and is from a peer-reviewed journal.

  17. (OpenTargets Search: -ANKFY1): Open Targets Query (-ANKFY1, 5 results). Buniello, A. et al. (2025). Open Targets Platform: facilitating therapeutic hypotheses building in drug discovery. Nucleic Acids Research.

  18. (schnatwinkel2004characterisationofnovel pages 134-138): C Schnatwinkel. Characterisation of novel rab5 effector proteins in the endocytic pathway. Unknown journal, 2004.

  19. (wei2024ankfy1bridgesatg2amediated media 1181e331): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

  20. (wei2024ankfy1bridgesatg2amediated media 5c7dbd2b): Bin Wei, Yuhui Fu, Xiuzhi Li, Fang Chen, Yiqing Zhang, Hanmo Chen, Mindan Tong, Linsen Li, Yi Pan, Shen Zhang, She Chen, Xiaoxia Liu, and Qing Zhong. Ankfy1 bridges atg2a-mediated lipid transfer from endosomes to phagophores. Cell Discovery, Apr 2024. URL: https://doi.org/10.1038/s41421-024-00659-y, doi:10.1038/s41421-024-00659-y. This article has 13 citations and is from a peer-reviewed journal.

Artifacts

Citations

  1. zhang2024compoundheterozygousvariants pages 1-3
  2. zhang2024compoundheterozygousvariants pages 3-4
  3. zhang2024compoundheterozygousvariants pages 4-5
  4. schnatwinkel2004characterisationofnovel pages 106-107
  5. schnatwinkel2004characterisationofnovel pages 101-104
  6. schnatwinkel2004characterisationofnovel pages 104-106
  7. schnatwinkel2004characterisationofnovel pages 134-138
  8. PI(3)P
  9. https://doi.org/10.1371/journal.pbio.0020261
  10. https://doi.org/10.1038/s41421-024-00659-y
  11. https://doi.org/10.1093/ckj/sfae124
  12. https://doi.org/10.1681/ASN.2017121312
  13. https://platform.opentargets.org/
  14. https://doi.org/10.1681/ASN.2017121312;
  15. https://doi.org/10.1371/journal.pbio.0020261,
  16. https://doi.org/10.1681/asn.2017121312,
  17. https://doi.org/10.1038/s41421-024-00659-y,
  18. https://doi.org/10.1093/ckj/sfae124,

๐Ÿ“š Additional Documentation

Notes

(ANKFY1-notes.md)

ANKFY1 Gene Review Notes

2026-06-03 - Proteostasis PN review

ANKFY1/Rabankyrin-5 is primarily supported as a PI3P- and Rab5-associated endosomal effector. The core 2004 study identifies Rabankyrin-5 as a PI(3)P-binding Rab5 effector that localizes to early endosomes, stimulates endosomal fusion, localizes to macropinosomes, and promotes fluid-phase uptake. [PMID:15328530 "novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which localises to early endosomes and stimulates their fusion activity"; PMID:15328530 "Overexpression of Rabankyrin-5 increases the number of macropinosomes and stimulates fluid-phase uptake, whereas its downregulation inhibits these processes."]

Retromer and receptor-trafficking evidence is also well supported. Zhang et al. show that Rank-5 interacts with EHD1 through the Rank-5 NPFED motif, colocalizes/interacts with retromer component VPS26, and that Rank-5 depletion disrupts mannose 6-phosphate receptor retrieval to the Golgi from endosomes and biosynthetic transport. [PMID:22284051 "binding occurs between the EH domain of EHD1 and the NPFED motif of Rank-5"; PMID:22284051 "depletion of Rank-5 causes mislocalization of Vps26 and affects both the retrieval of mannose 6-phosphate receptor transport to the Golgi from endosomes and biosynthetic transport."] RhoD work further supports a role in endosomal trafficking of activated receptor cargo. [PMID:24102721 "RhoD binds to the Rab5 effector Rabankyrin-5"; PMID:24102721 "internalization and trafficking of activated tyrosine kinase receptors."]

ANKFY1 also has direct autophagy-relevant evidence. Wei et al. identify ANKFY1 as an ATG2A-binding protein; ANKFY1 depletion impairs autophagosome growth and reduces autophagy flux; purified ANKFY1 binds PI3P through its FYVE domain and enhances ATG2A-mediated lipid transfer between PI3P-containing liposomes. [PMID:38622126 "identified a new ATG2A-binding protein, ANKFY1"; PMID:38622126 "impaired autophagosome growth and the reduced autophagy flux"; PMID:38622126 "enhanced ATG2A-mediated lipid transfer between PI3P-containing liposomes."]

PN projection assessment: the local PN projection currently proposes GO:1990756 ubiquitin-like ligase-substrate adaptor activity for ANKFY1 from Ubiquitin Proteasome System > E3 ubiquitin and UBL ligases > Cul3 substrate receptor > BTB-BACK, variant > ankyrin. This should not be propagated for ANKFY1 without gene-specific support. ANKFY1 has a BTB/POZ-related region, but the reviewed UniProt record and the ANKFY1 literature support Rab5/PI3P/endosomal trafficking and ATG2A-mediated autophagosome assembly, not validated CUL3 complex membership, substrate recognition for a ubiquitin-like ligase, or ubiquitin-like ligase-substrate adaptor activity. Curation conclusion: keep ANKFY1 as proteostasis-relevant through endosome-autophagosome lipid transfer, but exclude it from automatic UPS/Cul3 GO:1990756 propagation unless direct CUL3-substrate-adaptor evidence is found.

Pn Notes

(ANKFY1-pn-notes.md)

ANKFY1 PN Consistency Notes

  • Generated: 2026-06-18
  • Project: PROTEOSTASIS
  • Scope: PN consistency rereview against local AIGR review and available deep-research artifacts
  • UniProt: Q9P2R3
  • AIGR review status: COMPLETE
  • Review batch: proteostasis-batch-2026-06-03 (PR 1366)
  • Batch change status: added

Source Files Checked

Deep Research Files

AIGR Review Snapshot

  • Description: ANKFY1 encodes Rabankyrin-5, a large ankyrin-repeat, BTB/POZ, and FYVE-domain protein that acts on PI3P- and Rab5-positive endosomal membranes. It binds activated Rab5-family GTPases and phosphatidylinositol phosphate lipids to regulate early endosome fusion, macropinocytosis, retromer-dependent endosome-to-Golgi and Golgi-to-lysosome trafficking, and receptor internalization. Recent work shows that ANKFY1 also recruits and stabilizes ATG2A on PI3P-rich endosomal membranes during autophagy, promoting ATG2A-mediated lipid transfer from endosomes to phagophores for autophagosome growth and completion.
  • Existing/core annotation action counts: ACCEPT: 22; KEEP_AS_NON_CORE: 9; MODIFY: 4; NEW: 1; UNDECIDED: 2

PN Consistency Summary

  • Consistency: CONTRADICTION (placement-level). PN places ANKFY1 in UPS as a Cul3 substrate receptor (BTB/ankyrin domain architecture), but DR โ†” notes โ†” review YAML all curate ANKFY1 as a PI3P-/Rab5-binding endosomal effector (Rabankyrin-5) and ATG2A-bridging autophagy factor. GOA has NO ubiquitin-ligase/CUL3 terms (only GO:0031267 Rab5 binding, GO:1901981 PI3P binding). The UPS placement rests on domain signature (BTB-BACK/ankyrin), not function.
  • PN story / NEW pressure: PN's sole projected term GO:1990756 (verified real, new_to_goa): review explicitly REJECTS โ€” no validated CUL3 membership, substrate recognition, or adaptor activity for ANKFY1; the BTB region is present but not functionally ubiquitin-ligase. Over-reaches. Instead the review ADDS GO:0000045 autophagosome assembly (verified real; action: NEW, IMP, PMID:38622126 โ€” ANKFY1 depletion impairs autophagosome growth, enhances ATG2A lipid transfer). The genuine proteostasis link is ALP (autophagosome formation), not UPS.
  • Evidence alignment: PN cites PMID:15071497, 23912815 (titles only, generic). Review/notes anchor on PMID:15328530 (Rabankyrin-5/Rab5/PI3P), 22284051 (EHD1/retromer/M6PR), 24102721 (RhoD), and the key PMID:38622126 (ATG2A). No overlap with PN's cited PMIDs โ€” divergent evidence base reflecting the placement conflict.
  • Verdict: PN UPS/Cul3 placement and GO:1990756 projection over-reach; review correctly rejects and instead adds GO:0000045 (ALP). Domain-driven mis-placement.

Full Consistency Review

  • UniProt: Q9P2R3 (Rabankyrin-5) ยท batch: proteostasis-batch-2026-06-03 ยท review status: COMPLETE
  • PN placement: 1 row, UPS. Ubiquitin Proteasome System|E3 ubiquitin and UBL ligases|Cul3 substrate receptor|BTB-BACK, variant|ankyrin. PN-node mapping: group (Cul3 substrate receptor)=mappedโ†’GO:1990756 ubiquitin-like ligase-substrate adaptor activity (new_to_goa); class (E3 ligases)=context_onlyโ†’GO:0061630; subtype/type/branch=no_mapping.
  • Consistency: CONTRADICTION (placement-level). PN places ANKFY1 in UPS as a Cul3 substrate receptor (BTB/ankyrin domain architecture), but DR โ†” notes โ†” review YAML all curate ANKFY1 as a PI3P-/Rab5-binding endosomal effector (Rabankyrin-5) and ATG2A-bridging autophagy factor. GOA has NO ubiquitin-ligase/CUL3 terms (only GO:0031267 Rab5 binding, GO:1901981 PI3P binding). The UPS placement rests on domain signature (BTB-BACK/ankyrin), not function.
  • PN story / NEW pressure: PN's sole projected term GO:1990756 (verified real, new_to_goa): review explicitly REJECTS โ€” no validated CUL3 membership, substrate recognition, or adaptor activity for ANKFY1; the BTB region is present but not functionally ubiquitin-ligase. Over-reaches. Instead the review ADDS GO:0000045 autophagosome assembly (verified real; action: NEW, IMP, PMID:38622126 โ€” ANKFY1 depletion impairs autophagosome growth, enhances ATG2A lipid transfer). The genuine proteostasis link is ALP (autophagosome formation), not UPS.
  • Mapping strategy: ANKFY1 should be EXCLUDED from the Cul3-substrate-receptor GO:1990756 projection (domain-only mis-bucketing, analogous to the broader/wrong-bucket precedents). Its proteostasis relevance belongs in the autophagy branch via ATG2A-mediated phagophore growth.
  • Evidence alignment: PN cites PMID:15071497, 23912815 (titles only, generic). Review/notes anchor on PMID:15328530 (Rabankyrin-5/Rab5/PI3P), 22284051 (EHD1/retromer/M6PR), 24102721 (RhoD), and the key PMID:38622126 (ATG2A). No overlap with PN's cited PMIDs โ€” divergent evidence base reflecting the placement conflict.
  • Verdict: PN UPS/Cul3 placement and GO:1990756 projection over-reach; review correctly rejects and instead adds GO:0000045 (ALP). Domain-driven mis-placement.
  • Recommended edits: none to ANKFY1-ai-review.yaml. [MAP] exclude ANKFY1 from the Cul3-substrate-receptor GO:1990756 projection (no CUL3/adaptor evidence; function is Rab5/PI3P endosomal + ATG2A autophagy). Consider re-homing ANKFY1's proteostasis placement to ALP.

PN Dossier Context

  • review_batch: proteostasis-batch-2026-06-03
  • review_yaml: genes/human/ANKFY1/ANKFY1-ai-review.yaml
  • PN workbook rows: 1

PN row 1: Ubiquitin Proteasome System | E3 ubiquitin and UBL ligases | Cul3 substrate receptor | BTB-BACK, variant | ankyrin

  • UniProt: Q9P2R3
  • In branches: UPS
  • Signature domains: IPR000210, IPR049763
  • Auxiliary domains: IPR002110
  • PN references (titles):
    • 15071497 / rev
    • 23912815 / rev
  • PN-node mapping records (path + ancestors):
    • [subtype] Ubiquitin Proteasome System|E3 ubiquitin and UBL ligases|Cul3 substrate receptor|BTB-BACK, variant|ankyrin
      status=no_mapping scope= GO=[]
      rationale: Reviewed as a narrower substrate-receptor, adaptor, domain, or family subdivision already covered by the curated parent adaptor/receptor mapping. No additional direct GO mapping is needed at this node.
    • [type] Ubiquitin Proteasome System|E3 ubiquitin and UBL ligases|Cul3 substrate receptor|BTB-BACK, variant
      status=no_mapping scope= GO=[]
      rationale: Reviewed as a narrower substrate-receptor, adaptor, domain, or family subdivision already covered by the curated parent adaptor/receptor mapping. No additional direct GO mapping is needed at this node.
    • [group] Ubiquitin Proteasome System|E3 ubiquitin and UBL ligases|Cul3 substrate receptor
      status=mapped scope=ok_for_propagation_to_go GO=[GO:1990756 ubiquitin-like ligase-substrate adaptor activity]
      rationale: This PN group captures substrate receptors/adaptors for cullin/UBL ligase systems. The shared GO molecular-function target is ubiquitin-like ligase-substrate adaptor activity.
    • [class] Ubiquitin Proteasome System|E3 ubiquitin and UBL ligases
      status=context_only scope=too_broad_to_propagate GO=[GO:0061630 ubiquitin protein ligase activity]
      rationale: This class is a genuine E3-ligase context, but its descendants include catalytic ligases, cullin scaffolds, substrate receptors, adaptors, cofactors, regulators, and UBL modifier systems. A class-level propagation would over-annotate.
    • [branch] Ubiquitin Proteasome System
      status=no_mapping scope= GO=[]
      rationale: Reviewed as the top-level UPS branch. It is a project taxonomy umbrella rather than a direct GO assertion; UPS propagation must come from manually curated child nodes.

Projected GO annotations (1)

  • GO:1990756 ubiquitin-like ligase-substrate adaptor activity | scope=ok_for_propagation_to_go | goa_status=new_to_goa | from=Ubiquitin Proteasome System|E3 ubiquitin and UBL ligases|Cul3 substrate receptor

Note

This file is generated from the current PROTEOSTASIS phase-1 dossier and local gene-review artifacts. Edit the source review, PN mapping, or dossier rather than this generated note when correcting the underlying curation.

๐Ÿ“„ View Raw YAML

id: Q9P2R3
gene_symbol: ANKFY1
product_type: PROTEIN
status: COMPLETE
taxon:
  id: NCBITaxon:9606
  label: Homo sapiens
description: 'ANKFY1 encodes Rabankyrin-5, a large ankyrin-repeat, BTB/POZ, and FYVE-domain
  protein that acts on PI3P- and Rab5-positive endosomal membranes. It binds activated
  Rab5-family GTPases and phosphatidylinositol phosphate lipids to regulate early
  endosome fusion, macropinocytosis, retromer-dependent endosome-to-Golgi and Golgi-to-lysosome
  trafficking, and receptor internalization. Recent work shows that ANKFY1 also recruits
  and stabilizes ATG2A on PI3P-rich endosomal membranes during autophagy, promoting
  ATG2A-mediated lipid transfer from endosomes to phagophores for autophagosome growth
  and completion.'
alternative_products:
- name: '1'
  id: Q9P2R3-1
- name: '2'
  id: Q9P2R3-2
  sequence_note: VSP_035607
- name: '4'
  id: Q9P2R3-4
  sequence_note: VSP_041447
existing_annotations:
- term:
    id: GO:0010008
    label: endosome membrane
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: is_active_in
  review:
    summary: Endosome membrane localization/activity is well supported for
      ANKFY1/Rabankyrin-5.
    action: ACCEPT
    reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes
      on early/endosomal membranes; this location is central to its endosomal
      trafficking and ATG2A-bridging roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - &id003
      reference_id: PMID:15328530
      supporting_text: novel PI(3)P-binding Rab5 effector, Rabankyrin-5, which
        localises to early endosomes and stimulates their fusion activity
    - &id009
      reference_id: PMID:15328530
      supporting_text: Rabankyrin-5 binds most strongly to PI(3)P
    - &id007
      reference_id: PMID:38622126
      supporting_text: ANKFY1 recruits ATG2A to PI3P-enriched endosomes and
        promotes ATG2A-mediated lipid transfer from endosomes to phagophores
- term:
    id: GO:0031267
    label: small GTPase binding
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: enables
  review:
    summary: Small GTPase binding is directly supported by Rab5 and
      RhoD/RAB-family interaction evidence.
    action: ACCEPT
    reason: Rabankyrin-5 was identified as a GTP-dependent Rab5 effector, and
      additional disease/trafficking work supports interaction with
      RAB5-regulatory machinery; this is a core molecular function.
    additional_reference_ids:
    - PMID:15328530
    - PMID:24102721
    - PMID:29959197
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - &id010
      reference_id: PMID:15328530
      supporting_text: Rabankyrin-5 binds to Rab5 specifically, directly, and
        GTP dependently
    - &id013
      reference_id: PMID:24102721
      supporting_text: RhoD binds to the Rab5 effector Rabankyrin-5
    - &id006
      reference_id: PMID:29959197
      supporting_text: GAPVD1 and ANKFY1 interact with the endosomal regulator
        RAB5
- term:
    id: GO:0042147
    label: retrograde transport, endosome to Golgi
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: Endosome-to-Golgi retrograde transport is supported by
      Rank-5/retromer evidence.
    action: ACCEPT
    reason: Rank-5 interacts and colocalizes with retromer cargo-recognition
      components, and Rank-5 depletion impairs mannose 6-phosphate receptor
      retrieval from endosomes to the Golgi.
    additional_reference_ids: &id001
    - PMID:22284051
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - &id005
      reference_id: PMID:22284051
      supporting_text: Rank-5 colocalizes and interacts with components of the
        retromer complex such as vacuolar protein sorting 26 (Vps26)
    - &id002
      reference_id: PMID:22284051
      supporting_text: depletion of Rank-5 causes mislocalization of Vps26 and
        affects both the retrieval of mannose 6-phosphate receptor transport to
        the Golgi from endosomes and biosynthetic transport
- term:
    id: GO:0090160
    label: Golgi to lysosome transport
  evidence_type: IBA
  original_reference_id: GO_REF:0000033
  qualifier: involved_in
  review:
    summary: Golgi-to-lysosome/biosynthetic transport is supported as part of
      the Rank-5 retromer-trafficking phenotype.
    action: ACCEPT
    reason: The same Rank-5 depletion experiments that disrupt retromer
      distribution also affect biosynthetic transport, consistent with a role in
      endosome/Golgi/lysosome trafficking.
    additional_reference_ids: *id001
    supported_by:
    - *id002
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: Cytoplasmic localization is supported but is less informative than
      endosome-membrane localization.
    action: KEEP_AS_NON_CORE
    reason: ANKFY1 was initially described as a cytoplasmic protein and is
      present in soluble fractions, but the biologically informative location is
      its recruitment to PI3P/Rab5-positive endosomal membranes.
    additional_reference_ids:
    - PMID:10940552
    - PMID:15328530
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - &id004
      reference_id: PMID:10940552
      supporting_text: Ankhzn protein is ubiquitously expressed in a
        spatiotemporal-specific manner and is located on endosomes
    - &id008
      reference_id: PMID:10940552
      supporting_text: present in both membrane and soluble fractions obtained
        on subcellular fractionation
    - *id003
- term:
    id: GO:0005768
    label: endosome
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: located_in
  review:
    summary: Endosome localization is supported and relevant to ANKFY1 function.
    action: ACCEPT
    reason: The original ANKHZN paper and later Rabankyrin-5 studies place the
      protein on endosomes, where it binds Rab5/PI3P and coordinates endocytic
      trafficking.
    additional_reference_ids: &id012
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id004
    - *id003
- term:
    id: GO:0005769
    label: early endosome
  evidence_type: IEA
  original_reference_id: GO_REF:0000044
  qualifier: located_in
  review:
    summary: Early endosome localization is supported by Rabankyrin-5
      colocalization with Rab5/EEA1-positive compartments and later functional
      studies.
    action: ACCEPT
    reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal
      localization is required for endosomal fusion, retromer-related
      trafficking, and ATG2A recruitment during autophagy stimulation.
    additional_reference_ids:
    - PMID:15328530
    - PMID:22284051
    - PMID:29959197
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id003
    - *id005
    - *id006
    - *id007
- term:
    id: GO:0005829
    label: cytosol
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: located_in
  review:
    summary: Cytosol localization is supported as a source pool but is not the
      main functional location.
    action: KEEP_AS_NON_CORE
    reason: ANKFY1 occurs in soluble and membrane-associated fractions; the
      reviewed functional evidence points to membrane recruitment at
      PI3P/Rab5-positive endosomes.
    additional_reference_ids:
    - PMID:10940552
    - PMID:15328530
    supported_by:
    - *id008
    - *id003
- term:
    id: GO:0010008
    label: endosome membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000120
  qualifier: located_in
  review:
    summary: Endosome membrane localization/activity is well supported for
      ANKFY1/Rabankyrin-5.
    action: ACCEPT
    reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes
      on early/endosomal membranes; this location is central to its endosomal
      trafficking and ATG2A-bridging roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - *id003
    - *id009
    - *id007
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IEA
  original_reference_id: GO_REF:0000117
  qualifier: located_in
  review:
    summary: Generic membrane localization is supported but too broad to
      represent the core location.
    action: KEEP_AS_NON_CORE
    reason: Membrane association is real, but the more informative annotation is
      endosome membrane/early endosome, where ANKFY1 binds PI3P and functions
      with Rab5 and ATG2A.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - *id008
    - *id003
    - *id007
- term:
    id: GO:0046872
    label: metal ion binding
  evidence_type: IEA
  original_reference_id: GO_REF:0000002
  qualifier: enables
  review:
    summary: Metal ion binding is a broad domain-derived proxy for the FYVE zinc
      finger and should be replaced by the directly demonstrated lipid-binding
      activity.
    action: MODIFY
    reason: The FYVE domain is biologically important because it binds
      PI3P-containing membranes; direct lipid-binding experiments support
      phosphatidylinositol phosphate binding, while generic metal ion binding is
      not informative for ANKFY1 function.
    proposed_replacement_terms:
    - id: GO:1901981
      label: phosphatidylinositol phosphate binding
    additional_reference_ids:
    - PMID:15328530
    - PMID:38622126
    supported_by:
    - *id009
    - &id015
      reference_id: PMID:38622126
      supporting_text: enhanced ATG2A-mediated lipid transfer between
        PI3P-containing liposomes
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:15328530
  qualifier: enables
  supporting_entities:
  - UniProtKB:P20339
  review:
    summary: The generic protein-binding row reflects Rab5 interaction and
      should be replaced by small GTPase binding.
    action: MODIFY
    reason: The publication demonstrates specific, direct, GTP-dependent Rab5
      binding; GO:0031267 captures the molecular function better than generic
      protein binding.
    proposed_replacement_terms:
    - id: GO:0031267
      label: small GTPase binding
    additional_reference_ids:
    - PMID:15328530
    supported_by:
    - *id010
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:20562859
  qualifier: enables
  supporting_entities:
  - UniProtKB:P60520
  review:
    summary: The generic protein-binding row reflects ATG8/GABARAP-family
      association in a high-throughput autophagy network.
    action: MODIFY
    reason: The evidence is a proteomic autophagy-network interaction, so the
      more specific molecular-function replacement is ubiquitin-like protein
      binding; it should be treated as non-core relative to Rab5/PI3P/endosomal
      trafficking.
    proposed_replacement_terms:
    - id: GO:0032182
      label: ubiquitin-like protein binding
    additional_reference_ids:
    - PMID:20562859
    supported_by:
    - reference_id: PMID:20562859
      supporting_text: The six ATG8 orthologues in humans (MAP1LC3/GABARAP
        proteins) interact with a cohort of 67 proteins
    - reference_id: PMID:20562859
      supporting_text: FYVE domain-containing proteins FYCO1 and ANKFY1
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:22284051
  qualifier: enables
  supporting_entities:
  - UniProtKB:Q9H4M9
  review:
    summary: The generic protein-binding row reflects Rank-5 binding to the EHD1
      EH domain.
    action: MODIFY
    reason: Rank-5 contains an NPFED motif that binds the EHD1 EH domain;
      GO:1990175 EH domain binding captures this interaction better than generic
      protein binding.
    proposed_replacement_terms:
    - id: GO:1990175
      label: EH domain binding
    additional_reference_ids:
    - PMID:22284051
    supported_by:
    - &id011
      reference_id: PMID:22284051
      supporting_text: binding occurs between the EH domain of EHD1 and the
        NPFED motif of Rank-5
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:27189942
  qualifier: enables
  supporting_entities:
  - UniProtKB:Q9H4M9
  review:
    summary: The local cached article does not provide ANKFY1-specific text for
      this generic EHD1/Q9H4M9 interaction row.
    action: UNDECIDED
    reason: The abstract supports EHD paralog binding to NPF-containing partners
      generally, but the cached text available locally does not document the
      ANKFY1/Rabankyrin-5 interaction with EHD1 specifically. A replacement such
      as EH domain binding may be appropriate if full interaction evidence is
      checked, but this row should remain undecided until the specific evidence
      is accessible.
    additional_reference_ids:
    - PMID:27189942
    - PMID:22284051
    supported_by:
    - reference_id: PMID:27189942
      supporting_text: EHD proteins have an EH domain that interacts with
        proteins containing an NPF motif
    - *id011
- term:
    id: GO:0005515
    label: protein binding
  evidence_type: IPI
  original_reference_id: PMID:27189942
  qualifier: enables
  supporting_entities:
  - UniProtKB:Q9NZN3
  review:
    summary: The local cached article does not provide ANKFY1-specific text for
      this generic EHD3/Q9NZN3 interaction row.
    action: UNDECIDED
    reason: The GOA includes a distinct PMID:27189942 IPI row for EHD3/Q9NZN3.
      The cached abstract supports EHD-family EH-domain recognition of
      NPF-containing partners and distinguishes EHD1 from EHD3, but it does not
      expose ANKFY1/Rabankyrin-5-specific interaction evidence for this partner.
      This row should remain undecided until the specific IntAct/full-text
      evidence is accessible.
    additional_reference_ids:
    - PMID:27189942
    - PMID:22284051
    supported_by:
    - reference_id: PMID:27189942
      supporting_text: EHD proteins have an EH domain that interacts with
        proteins containing an NPF motif
    - reference_id: PMID:27189942
      supporting_text: EHD1 and EHD3 have 86% amino acid identity; they homo-
        and heterodimerize and partially co-localize to TRE
- term:
    id: GO:0005768
    label: endosome
  evidence_type: IDA
  original_reference_id: GO_REF:0000052
  qualifier: located_in
  review:
    summary: Endosome localization is supported and relevant to ANKFY1 function.
    action: ACCEPT
    reason: The original ANKHZN paper and later Rabankyrin-5 studies place the
      protein on endosomes, where it binds Rab5/PI3P and coordinates endocytic
      trafficking.
    additional_reference_ids: *id012
    supported_by:
    - *id004
    - *id003
- term:
    id: GO:0005737
    label: cytoplasm
  evidence_type: EXP
  original_reference_id: PMID:10940552
  qualifier: located_in
  review:
    summary: Cytoplasmic localization is supported but is less informative than
      endosome-membrane localization.
    action: KEEP_AS_NON_CORE
    reason: ANKFY1 was initially described as a cytoplasmic protein and is
      present in soluble fractions, but the biologically informative location is
      its recruitment to PI3P/Rab5-positive endosomal membranes.
    additional_reference_ids:
    - PMID:10940552
    - PMID:15328530
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id004
    - *id008
    - *id003
- term:
    id: GO:0005769
    label: early endosome
  evidence_type: EXP
  original_reference_id: PMID:22284051
  qualifier: located_in
  review:
    summary: Early endosome localization is supported by Rabankyrin-5
      colocalization with Rab5/EEA1-positive compartments and later functional
      studies.
    action: ACCEPT
    reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal
      localization is required for endosomal fusion, retromer-related
      trafficking, and ATG2A recruitment during autophagy stimulation.
    additional_reference_ids:
    - PMID:15328530
    - PMID:22284051
    - PMID:29959197
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id003
    - *id005
    - *id006
    - *id007
- term:
    id: GO:0005769
    label: early endosome
  evidence_type: EXP
  original_reference_id: PMID:29959197
  qualifier: located_in
  review:
    summary: Early endosome localization is supported by Rabankyrin-5
      colocalization with Rab5/EEA1-positive compartments and later functional
      studies.
    action: ACCEPT
    reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal
      localization is required for endosomal fusion, retromer-related
      trafficking, and ATG2A recruitment during autophagy stimulation.
    additional_reference_ids:
    - PMID:15328530
    - PMID:22284051
    - PMID:29959197
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id003
    - *id005
    - *id006
    - *id007
- term:
    id: GO:0010008
    label: endosome membrane
  evidence_type: EXP
  original_reference_id: PMID:10940552
  qualifier: located_in
  review:
    summary: Endosome membrane localization/activity is well supported for
      ANKFY1/Rabankyrin-5.
    action: ACCEPT
    reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes
      on early/endosomal membranes; this location is central to its endosomal
      trafficking and ATG2A-bridging roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - *id003
    - *id009
    - *id007
- term:
    id: GO:0010008
    label: endosome membrane
  evidence_type: TAS
  original_reference_id: Reactome:R-HSA-9013438
  qualifier: located_in
  review:
    summary: Endosome membrane localization/activity is well supported for
      ANKFY1/Rabankyrin-5.
    action: ACCEPT
    reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes
      on early/endosomal membranes; this location is central to its endosomal
      trafficking and ATG2A-bridging roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - *id003
    - *id009
    - *id007
- term:
    id: GO:0070062
    label: extracellular exosome
  evidence_type: HDA
  original_reference_id: PMID:18570454
  qualifier: located_in
  review:
    summary: Extracellular exosome detection comes from high-throughput
      proteomics and is not central to ANKFY1 function.
    action: KEEP_AS_NON_CORE
    reason: The exosome rows may reflect proteomic detection, but they do not
      explain the core Rab5/PI3P/endosomal trafficking and ATG2A
      autophagosome-assembly roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:20562859
    - PMID:38622126
    supported_by:
    - *id003
    - &id016
      reference_id: PMID:20562859
      supporting_text: depletion of ANKFY1 also led to increased autophagosomal
        number without blocking flux
    - *id007
- term:
    id: GO:0016197
    label: endosomal transport
  evidence_type: IMP
  original_reference_id: PMID:24102721
  qualifier: involved_in
  review:
    summary: Endosomal transport is supported by RhoD/PDGFR trafficking and the
      broader Rabankyrin-5 endosomal phenotype.
    action: ACCEPT
    reason: RhoD and Rabankyrin-5 coordinate Rab/Rho activities during
      internalization and trafficking of activated receptor cargo; this is
      consistent with the core endosomal transport function.
    additional_reference_ids:
    - PMID:24102721
    - PMID:15328530
    - PMID:22284051
    supported_by:
    - &id017
      reference_id: PMID:24102721
      supporting_text: coordinating RhoD and Rab activities during
        internalization and trafficking of activated tyrosine kinase receptors
    - *id003
    - *id002
- term:
    id: GO:0030904
    label: retromer complex
  evidence_type: IDA
  original_reference_id: PMID:22284051
  qualifier: colocalizes_with
  review:
    summary: Retromer complex colocalization is supported, but ANKFY1 is not
      established as a retromer complex subunit.
    action: KEEP_AS_NON_CORE
    reason: The qualifier is colocalizes_with, and the evidence shows
      interaction/colocalization with VPS26 and retromer distribution defects
      rather than stable retromer-complex membership.
    additional_reference_ids:
    - PMID:22284051
    supported_by:
    - *id005
    - *id002
- term:
    id: GO:0042147
    label: retrograde transport, endosome to Golgi
  evidence_type: IMP
  original_reference_id: PMID:22284051
  qualifier: involved_in
  review:
    summary: Endosome-to-Golgi retrograde transport is supported by
      Rank-5/retromer evidence.
    action: ACCEPT
    reason: Rank-5 interacts and colocalizes with retromer cargo-recognition
      components, and Rank-5 depletion impairs mannose 6-phosphate receptor
      retrieval from endosomes to the Golgi.
    additional_reference_ids: *id001
    supported_by:
    - *id005
    - *id002
- term:
    id: GO:0090160
    label: Golgi to lysosome transport
  evidence_type: IMP
  original_reference_id: PMID:22284051
  qualifier: involved_in
  review:
    summary: Golgi-to-lysosome/biosynthetic transport is supported as part of
      the Rank-5 retromer-trafficking phenotype.
    action: ACCEPT
    reason: The same Rank-5 depletion experiments that disrupt retromer
      distribution also affect biosynthetic transport, consistent with a role in
      endosome/Golgi/lysosome trafficking.
    additional_reference_ids: *id001
    supported_by:
    - *id002
- term:
    id: GO:0005769
    label: early endosome
  evidence_type: IDA
  original_reference_id: PMID:15328530
  qualifier: located_in
  review:
    summary: Early endosome localization is supported by Rabankyrin-5
      colocalization with Rab5/EEA1-positive compartments and later functional
      studies.
    action: ACCEPT
    reason: ANKFY1/Rabankyrin-5 localizes to early endosomes and its endosomal
      localization is required for endosomal fusion, retromer-related
      trafficking, and ATG2A recruitment during autophagy stimulation.
    additional_reference_ids:
    - PMID:15328530
    - PMID:22284051
    - PMID:29959197
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id003
    - *id005
    - *id006
    - *id007
- term:
    id: GO:0031267
    label: small GTPase binding
  evidence_type: IDA
  original_reference_id: PMID:15328530
  qualifier: enables
  review:
    summary: Small GTPase binding is directly supported by Rab5 and
      RhoD/RAB-family interaction evidence.
    action: ACCEPT
    reason: Rabankyrin-5 was identified as a GTP-dependent Rab5 effector, and
      additional disease/trafficking work supports interaction with
      RAB5-regulatory machinery; this is a core molecular function.
    additional_reference_ids:
    - PMID:15328530
    - PMID:24102721
    - PMID:29959197
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    supported_by:
    - *id010
    - *id013
    - *id006
- term:
    id: GO:0034058
    label: endosomal vesicle fusion
  evidence_type: IDA
  original_reference_id: PMID:15328530
  qualifier: involved_in
  review:
    summary: Endosomal vesicle fusion is directly supported by the original
      Rabankyrin-5 functional study.
    action: ACCEPT
    reason: Rabankyrin-5 is a Rab5/PI3P effector that stimulates early-endosome
      fusion and affects endosomal vesicle dynamics.
    additional_reference_ids:
    - PMID:15328530
    supported_by:
    - *id003
    - reference_id: PMID:15328530
      supporting_text: Rabankyrin-5 is a Rab5 effector required for the
        formation of macropinosomes
- term:
    id: GO:0044354
    label: macropinosome
  evidence_type: IDA
  original_reference_id: PMID:15328530
  qualifier: located_in
  review:
    summary: Macropinosome localization is directly supported and relevant to
      the pinocytosis phenotype.
    action: ACCEPT
    reason: Rabankyrin-5 localizes to macropinosomes and its perturbation
      changes fluid-phase uptake.
    additional_reference_ids:
    - PMID:15328530
    supported_by:
    - &id014
      reference_id: PMID:15328530
      supporting_text: Overexpression of Rabankyrin-5 increases the number of
        macropinosomes and stimulates fluid-phase uptake, whereas its
        downregulation inhibits these processes
- term:
    id: GO:0048549
    label: positive regulation of pinocytosis
  evidence_type: IDA
  original_reference_id: PMID:15328530
  qualifier: involved_in
  review:
    summary: Positive regulation of pinocytosis is directly supported.
    action: ACCEPT
    reason: Overexpression and depletion experiments show that Rabankyrin-5
      promotes fluid-phase/macropinocytic uptake, including apical
      non-clathrin-mediated uptake in polarized cells.
    additional_reference_ids:
    - PMID:15328530
    supported_by:
    - *id014
    - reference_id: PMID:15328530
      supporting_text: specifically stimulates apical, non-clathrin-mediated
        fluid-phase endocytosis
- term:
    id: GO:1901981
    label: phosphatidylinositol phosphate binding
  evidence_type: IDA
  original_reference_id: PMID:15328530
  qualifier: enables
  review:
    summary: Phosphatidylinositol phosphate binding is a core ANKFY1 molecular
      function.
    action: ACCEPT
    reason: ANKFY1/Rabankyrin-5 binds PI3P via its FYVE domain; this
      lipid-binding activity explains endosomal recruitment and is required for
      ATG2A-mediated lipid-transfer enhancement.
    additional_reference_ids:
    - PMID:15328530
    - PMID:38622126
    supported_by:
    - *id009
    - *id015
- term:
    id: GO:0070062
    label: extracellular exosome
  evidence_type: HDA
  original_reference_id: PMID:19056867
  qualifier: located_in
  review:
    summary: Extracellular exosome detection comes from high-throughput
      proteomics and is not central to ANKFY1 function.
    action: KEEP_AS_NON_CORE
    reason: The exosome rows may reflect proteomic detection, but they do not
      explain the core Rab5/PI3P/endosomal trafficking and ATG2A
      autophagosome-assembly roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:20562859
    - PMID:38622126
    supported_by:
    - *id003
    - *id016
    - *id007
- term:
    id: GO:0005765
    label: lysosomal membrane
  evidence_type: HDA
  original_reference_id: PMID:17897319
  qualifier: located_in
  review:
    summary: Lysosomal membrane detection is plausible but high-throughput and
      not core.
    action: KEEP_AS_NON_CORE
    reason: The dominant evidence places ANKFY1 on early/endosomal membranes;
      lysosomal-membrane proteomic detection is peripheral and should not drive
      the core function summary.
    additional_reference_ids:
    - PMID:15328530
    - PMID:38622126
    supported_by:
    - *id003
    - *id007
- term:
    id: GO:0016020
    label: membrane
  evidence_type: IDA
  original_reference_id: PMID:10940552
  qualifier: located_in
  review:
    summary: Generic membrane localization is supported but too broad to
      represent the core location.
    action: KEEP_AS_NON_CORE
    reason: Membrane association is real, but the more informative annotation is
      endosome membrane/early endosome, where ANKFY1 binds PI3P and functions
      with Rab5 and ATG2A.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - *id008
    - *id003
    - *id007
- term:
    id: GO:0010008
    label: endosome membrane
  evidence_type: ISS
  original_reference_id: GO_REF:0000024
  qualifier: located_in
  review:
    summary: Endosome membrane localization/activity is well supported for
      ANKFY1/Rabankyrin-5.
    action: ACCEPT
    reason: ANKFY1 is a FYVE-domain Rab5 effector that binds PI3P and localizes
      on early/endosomal membranes; this location is central to its endosomal
      trafficking and ATG2A-bridging roles.
    additional_reference_ids:
    - PMID:15328530
    - PMID:10940552
    - file:human/ANKFY1/ANKFY1-uniprot.txt
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    supported_by:
    - *id003
    - *id009
    - *id007
- term:
    id: GO:0000045
    label: autophagosome assembly
  evidence_type: IMP
  original_reference_id: PMID:38622126
  qualifier: involved_in
  review:
    summary: ANKFY1 should be added to autophagosome assembly for its
      ATG2A-dependent endosome-to-phagophore lipid-transfer role.
    action: NEW
    reason: ANKFY1 depletion impairs autophagosome growth, reduces autophagy
      flux, and phenocopies ATG2A/B depletion; in vitro ANKFY1 enhances
      ATG2A-mediated lipid transfer between PI3P-containing membranes.
      GO:0000045 is the conservative process term for this
      phagophore-growth/autophagosome-completion role.
    additional_reference_ids:
    - PMID:38622126
    - file:human/ANKFY1/ANKFY1-notes.md
    - file:human/ANKFY1/ANKFY1-deep-research-falcon.md
    supported_by:
    - &id018
      reference_id: PMID:38622126
      supporting_text: identified a new ATG2A-binding protein, ANKFY1
    - &id019
      reference_id: PMID:38622126
      supporting_text: Depletion of this endosome-localized protein led to the
        impaired autophagosome growth and the reduced autophagy flux
    - *id015
    - *id007
    - reference_id: file:human/ANKFY1/ANKFY1-deep-research-falcon.md
      supporting_text: A 2024 study identified ANKFY1 as an ATG2A-binding
        endosomal factor that bridges endosomes and phagophores, promoting
        ATG2A-mediated lipid transfer for phagophore growth
references:
- id: GO_REF:0000002
  title: Gene Ontology annotation through association of InterPro records with
    GO terms
  findings: []
- id: GO_REF:0000024
  title: Manual transfer of experimentally-verified manual GO annotation data to
    orthologs by curator judgment of sequence similarity
  findings: []
- id: GO_REF:0000033
  title: Annotation inferences using phylogenetic trees
  findings: []
- id: GO_REF:0000044
  title: Gene Ontology annotation based on UniProtKB/Swiss-Prot Subcellular
    Location vocabulary mapping, accompanied by conservative changes to GO terms
    applied by UniProt
  findings: []
- id: GO_REF:0000052
  title: Gene Ontology annotation based on curation of immunofluorescence data
  findings: []
- id: GO_REF:0000117
  title: Electronic Gene Ontology annotations created by ARBA machine learning
    models
  findings: []
- id: GO_REF:0000120
  title: Combined Automated Annotation using Multiple IEA Methods
  findings: []
- id: PMID:10940552
  title: Characterization and chromosomal mapping of a novel human gene, ANKHZN.
  findings: []
- id: PMID:15328530
  title: The Rab5 effector Rabankyrin-5 regulates and coordinates different
    endocytic mechanisms.
  findings: []
- id: PMID:17897319
  title: Integral and associated lysosomal membrane proteins.
  findings: []
- id: PMID:18570454
  title: Proteomic analysis of exosomes from human neural stem cells by flow
    field-flow fractionation and nanoflow liquid chromatography-tandem mass
    spectrometry.
  findings: []
- id: PMID:19056867
  title: Large-scale proteomics and phosphoproteomics of urinary exosomes.
  findings: []
- id: PMID:20562859
  title: Network organization of the human autophagy system.
  findings: []
- id: PMID:22284051
  title: Rabankyrin-5 interacts with EHD1 and Vps26 to regulate endocytic
    trafficking and retromer function.
  findings: []
- id: PMID:24102721
  title: RhoD binds the Rab5 effector Rabankyrin-5 and has a role in trafficking
    of the platelet-derived growth factor receptor.
  findings: []
- id: PMID:27189942
  title: EHD3 Protein Is Required for Tubular Recycling Endosome Stabilization,
    and an Asparagine-Glutamic Acid Residue Pair within Its Eps15 Homology (EH)
    Domain Dictates Its Selective Binding to NPF Peptides.
  findings: []
- id: PMID:29959197
  title: GAPVD1 and ANKFY1 Mutations Implicate RAB5 Regulation in Nephrotic
    Syndrome.
  findings: []
- id: Reactome:R-HSA-9013438
  title: RHOD binds effectors at the endosome membrane
  findings: []
- id: PMID:38622126
  title: ANKFY1 bridges ATG2A-mediated lipid transfer from endosomes to
    phagophores.
  findings:
  - statement: ANKFY1 binds ATG2A during autophagy stimulation and promotes
      ATG2A-mediated lipid transfer from endosomes to phagophores.
  - statement: ANKFY1 depletion impairs autophagosome growth and reduces
      autophagy flux.
- id: file:human/ANKFY1/ANKFY1-uniprot.txt
  title: UniProtKB record for human ANKFY1/Rabankyrin-5
  findings:
  - statement: UniProt summarizes ANKFY1 as a Rab5 effector involved in
      endosomal trafficking, macropinocytosis, receptor internalization,
      retromer-mediated transport, and podocyte migration.
- id: file:human/ANKFY1/ANKFY1-notes.md
  title: ANKFY1 review notes for Proteostasis PN assessment
  findings:
  - statement: The PN Cul3 substrate-receptor projection to GO:1990756 is not
      supported by ANKFY1-specific evidence.
  - statement: ANKFY1 is proteostasis-relevant through endosome-autophagosome
      lipid transfer rather than validated ubiquitin-like ligase-substrate
      adaptor activity.
- id: file:human/ANKFY1/ANKFY1-deep-research-falcon.md
  title: Falcon deep research report for human ANKFY1
  findings:
  - statement: The Falcon report summarizes ANKFY1 as a Rab5/PI3P endosomal
      scaffold with recent ATG2A-mediated autophagy evidence.
- id: projects/PROTEOSTASIS/reports/pn_projection/pn_projected_annotations.tsv
  title: Proteostasis PN projected annotations report
  findings:
  - statement: The report projects GO:1990756 to ANKFY1 from the Cul3 substrate
      receptor PN group.
core_functions:
- description: ANKFY1 is a Rab5/PI3P-positive endosomal effector that
    coordinates early endosome fusion, macropinocytosis, endosomal transport,
    and retromer-associated endosome-to-Golgi and Golgi-to-lysosome trafficking.
  molecular_function:
    id: GO:0031267
    label: small GTPase binding
  directly_involved_in:
  - id: GO:0034058
    label: endosomal vesicle fusion
  - id: GO:0048549
    label: positive regulation of pinocytosis
  - id: GO:0016197
    label: endosomal transport
  - id: GO:0042147
    label: retrograde transport, endosome to Golgi
  - id: GO:0090160
    label: Golgi to lysosome transport
  locations:
  - id: GO:0010008
    label: endosome membrane
  - id: GO:0005769
    label: early endosome
  - id: GO:0044354
    label: macropinosome
  supported_by:
  - *id010
  - *id009
  - *id014
  - *id002
  - *id017
- description: ANKFY1 binds PI3P-rich endosomal membranes through its FYVE
    domain and promotes ATG2A-mediated lipid transfer from endosomes to
    phagophores, supporting autophagosome growth and completion during autophagy
    induction.
  molecular_function:
    id: GO:1901981
    label: phosphatidylinositol phosphate binding
  directly_involved_in:
  - id: GO:0000045
    label: autophagosome assembly
  locations:
  - id: GO:0010008
    label: endosome membrane
  - id: GO:0005769
    label: early endosome
  supported_by:
  - *id018
  - *id019
  - *id015
  - *id007
  - reference_id: file:human/ANKFY1/ANKFY1-notes.md
    supporting_text: ANKFY1 also has direct autophagy-relevant evidence
proposed_new_terms: []
suggested_questions:
- question: Is there direct experimental evidence that ANKFY1 binds CUL3 or
    functions as a CRL3/ubiquitin-like ligase substrate adaptor in cells?
  experts:
  - GO ubiquitin-proteasome curators
  - Proteostasis PN curators
- question: Should ANKFY1 autophagy annotation be limited to autophagosome
    assembly, or should a more specific future term capture
    endosome-to-phagophore lipid-transfer bridging by ATG2A adaptors?
  experts:
  - GO autophagy editors
suggested_experiments:
- experiment_type: Endogenous CUL3 complex and ubiquitination assay
  hypothesis: ANKFY1 does not function as a CRL3 substrate receptor unless it
    shows endogenous CUL3 complex membership and substrate-dependent
    ubiquitination activity.
  description: Test endogenous ANKFY1-CUL3 binding by reciprocal
    co-immunoprecipitation or proximity labeling, identify candidate substrates,
    and determine whether ANKFY1 loss changes CUL3-dependent ubiquitination of
    those substrates.
- experiment_type: ANKFY1 autophagy rescue assay
  hypothesis: FYVE-dependent endosomal recruitment and ATG2A binding are
    required for ANKFY1 support of phagophore growth.
  description: Rescue ANKFY1 knockout cells with wild-type, FYVE-deleted, and
    ATG2A-binding-defective ANKFY1 variants, then assay Halo-LC3 autophagosome
    completion, LC3 flux, WIPI2/LC3 phagophore PI3P, and in vitro ATG2A lipid
    transfer.