DNAAF1 (AGAP009594) is the Anopheles gambiae ortholog of human DNAAF1 (formerly LRRC50) and Chlamydomonas ODA7. It is a cytoplasmic leucine-rich repeat protein that functions as a dynein arm assembly factor, required for the preassembly of both outer dynein arm (ODA) and inner dynein arm (IDA) complexes in the cytoplasm before their transport into the ciliary/flagellar axoneme. The protein operates as part of a chaperone complex with the AAA+ ATPases RUVBL1/RUVBL2 (Pontin/Reptin) and couples dynein assembly to intraflagellar transport via interaction with IFT88. Loss of function in orthologs across zebrafish, human, and Chlamydomonas results in absence of both ODA and IDA from axonemes, immotile cilia/flagella, and primary ciliary dyskinesia. In Anopheles gambiae, DNAAF1 is predicted to be essential for sperm flagellar motility and potentially chordotonal organ function. All GO annotations are inferred from orthologs by sequence similarity or phylogenetic inference.
| GO Term | Evidence | Action | Reason |
|---|---|---|---|
|
GO:0070840
dynein complex binding
|
ISS
GO_REF:0000024 |
ACCEPT |
Summary: Correct annotation. DNAAF1/LRRC50/ODA7 binds dynein complexes as its core molecular function. The Chlamydomonas ortholog ODA7 interacts with both outer row dynein and I1 inner row dynein. This binding is required for cytoplasmic preassembly of dynein arm complexes.
Supporting Evidence:
PMID:17194703
Oda7 participates in a previously uncharacterized structural link between inner and outer row dyneins
file:ANOGA/DNAAF1/DNAAF1-deep-research-bioreason-sft.md
The BioReason report identifies IPR050576 (Ciliary and flagellar integrity-associated protein family) covering the entire protein, consistent with ciliary function
|
|
GO:0070840
dynein complex binding
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: Redundant with the ISS annotation above. Both correctly capture the core molecular function of dynein complex binding.
Supporting Evidence:
PMID:17194703
Oda7 participates in a previously uncharacterized structural link between inner and outer row dyneins
|
|
GO:0007368
determination of left/right symmetry
|
IBA
GO_REF:0000033 |
KEEP AS NON CORE |
Summary: This annotation reflects the role of DNAAF1 in left-right axis determination, which depends on motile cilia at the embryonic node. DNAAF1 mutations in humans cause situs inversus and congenital heart defects through loss of nodal ciliary motility. However, determination of left/right symmetry is a vertebrate-specific process involving nodal cilia, and its applicability to Anopheles gambiae is questionable since insects do not use nodal cilia for left-right patterning. This IBA annotation may be an over-extension of vertebrate biology to an insect.
Reason: Left-right symmetry determination via nodal cilia is a vertebrate mechanism. While the IBA annotation from phylogenetic inference is technically valid, this process is unlikely to occur in Anopheles gambiae which does not have vertebrate-style nodal cilia. Kept as non-core rather than removed because the phylogenetic inference is methodologically sound even if the biological relevance to this species is uncertain.
Supporting Evidence:
PMID:29228333
DNAAF1-RUVBL1 biochemical and genetic interactions have a novel functional role in symmetry breaking and cardiac development
|
|
GO:0035082
axoneme assembly
|
IBA
GO_REF:0000033 |
ACCEPT |
Summary: Correct and core annotation. DNAAF1 is directly required for axoneme assembly through its role in preassembling dynein arm complexes in the cytoplasm. Loss of DNAAF1 orthologs results in axonemes lacking both outer and inner dynein arms.
Supporting Evidence:
PMID:19944400
combined defect involving assembly of the ODAs and IDAs
|
|
GO:0060271
cilium assembly
|
ISS
GO_REF:0000024 |
KEEP AS NON CORE |
Summary: Appropriate annotation. DNAAF1 contributes to cilium assembly by enabling the cytoplasmic preassembly of dynein arm complexes that are then transported into the cilium. However, the more specific term GO:0035082 (axoneme assembly) better captures the precise step at which DNAAF1 acts. DNAAF1 is not involved in ciliogenesis per se (basal body formation, transition zone assembly) but specifically in the assembly of dynein arms that are components of the axoneme.
Reason: While cilium assembly is technically correct, DNAAF1 specifically acts at the level of axoneme assembly (dynein arm preassembly). The more specific term GO:0035082 is the core annotation. Cilium assembly is retained as non-core because it is not incorrect, just less precise.
Supporting Evidence:
PMID:19944405
support a key role for LRRC50, a member of the leucine-rich-repeat superfamily, in cytoplasmic preassembly of dynein arms
|
|
GO:0005930
axoneme
|
IBA
GO_REF:0000033 |
KEEP AS NON CORE |
Summary: The Chlamydomonas ortholog ODA7 is found associated with the axoneme where it forms a structural link between inner and outer dynein arms. However, DNAAF1 primarily functions in the cytoplasm as an assembly factor. The axonemal localization may reflect the final destination of assembled dynein complexes rather than the primary site of DNAAF1 activity.
Reason: DNAAF1 primarily functions in the cytoplasm during dynein arm preassembly. Some axonemal association is documented for the Chlamydomonas ortholog ODA7, but the primary functional site is cytoplasmic. Kept as non-core.
Supporting Evidence:
PMID:17194703
Oda7 participates in a previously uncharacterized structural link between inner and outer row dyneins
|
|
GO:0005930
axoneme
|
ISS
GO_REF:0000024 |
KEEP AS NON CORE |
Summary: Consistent with the IBA annotation above. DNAAF1/ODA7 has been found associated with the axoneme in Chlamydomonas.
Reason: The primary site of activity is the cytoplasm, but axonemal localization is documented for the ortholog. Kept as non-core.
Supporting Evidence:
PMID:17194703
Oda7 participates in a previously uncharacterized structural link between inner and outer row dyneins
|
|
GO:0005929
cilium
|
IEA
GO_REF:0000044 |
KEEP AS NON CORE |
Summary: Consistent with the axoneme localization. The cilium is the parent structure containing the axoneme. LRRC50 has been localized to the ciliary structure in zebrafish and human cells.
Reason: Correct but less specific than the axoneme annotation. The primary functional site is the cytoplasm.
Supporting Evidence:
PMID:18385425
Subcellular distribution of human LRRC50-EGFP in MDCK and HEK293T cells is diffusely cytoplasmic and concentrated at the mitotic spindle poles and cilium
|
|
GO:0005737
cytoplasm
|
ISS
PMID:18385425 LRRC50, a Conserved Ciliary Protein Implicated in Polycystic... |
NEW |
Summary: DNAAF1 primarily functions in the cytoplasm where it assembles dynein arm complexes before their transport into the cilium. Human LRRC50-EGFP shows diffuse cytoplasmic distribution. This is the primary site of DNAAF1 activity as a dynein arm assembly factor.
Reason: The cytoplasmic localization is well-supported and represents the primary functional site of DNAAF1, where dynein arm preassembly occurs. This annotation is important because it distinguishes the assembly site (cytoplasm) from the destination (axoneme/cilium).
Supporting Evidence:
PMID:18385425
Subcellular distribution of human LRRC50-EGFP in MDCK and HEK293T cells is diffusely cytoplasmic and concentrated at the mitotic spindle poles and cilium
|
Q: Does DNAAF1 in Anopheles gambiae function specifically in sperm flagellar dynein assembly, and does its loss cause male sterility in mosquitoes?
Q: Is the IBA annotation for left-right symmetry determination biologically relevant in insects, or is this a vertebrate-specific function that should not be transferred to Anopheles?
Experiment: CRISPR knockout of AGAP009594 (DNAAF1) in Anopheles gambiae to assess effects on sperm flagellar motility and male fertility.
Experiment: Transmission electron microscopy of sperm flagella in DNAAF1 knockdown mosquitoes to determine whether outer and inner dynein arms are absent from the axoneme, as observed in vertebrate orthologs.
The LRR scaffold can also tune calcium-mediated signaling (GO:0050848) by docking calcium channels, pumps, or calcium-sensitive enzymes at defined cytoplasmic locales, thereby modulating local Ca2+ microdomains that feed back on MAPK and ciliary functions. In neurons, the same spatial organization supports axo-dendritic transport (GO:0008088) by linking cargoes to microtubule-based motors and adaptors, ensuring directional trafficking of receptors and organelles into dendrites and axons. Because spatial control of signaling and transport often impinges on transcriptional outputs, the scaffold’s regulation of these pathways can culminate in positive regulation of gene expression (GO:0010628), for example by stabilizing transcriptional co-regulators or by modulating signaling axes that enhance gene expression programs.
The cellular component is cytoplasm (GO:0005737), consistent with a soluble adaptor that assembles complexes in the cytosol and at cytoplasmic faces of organelles such as the basal body/ciliary base. The absence of transmembrane domains and the presence of extensive LRRs further support a cytoplasmic scaffold role rather than a membrane-embedded or nuclear role.
Mechanistically, I propose that the N-terminal LRR array nucleates binding of multi-protein assemblies—such as intraflagellar transport particles, kinesin/dynein motors, and signaling complexes—while the broader ciliary integrity family scaffold stabilizes these interactions long enough to direct cargo to the ciliary base or neuronal processes. By selectively recruiting or excluding components of the Smoothened and RAF–MEK–ERK modules, and by positioning calcium-handling proteins, the protein tunes pathway amplitude and timing. In neurons, coupling to microtubule motors and dendritic trafficking adaptors extends this spatial control to axo-dendritic transport, ultimately influencing gene expression through signaling-dependent transcriptional programs.
## Functional Summary
A cytoplasmic leucine‑rich repeat scaffold that assembles and positions large protein complexes to control signaling and transport. Its N‑terminal repeat array provides a high‑affinity docking surface that captures transport and signaling modules, while the extended scaffold stabilizes these assemblies to direct them toward the ciliary base and neuronal processes. Through spatial sequestration and delivery of components, it dampens Smoothened‑dependent Hedgehog signaling, restrains ERK1/2 activation, modulates calcium‑dependent signaling microdomains, and supports axo‑dendritic cargo trafficking. These coordinated actions can ultimately enhance gene expression programs downstream of the tuned signaling outputs.
## UniProt Summary
Negatively regulates the Hedgehog (Hh) signaling pathway, possibly by regulating the activity of smoothened ( smo ).
## InterPro Domains
- IPR032675: Leucine-rich repeat domain superfamily (homologous_superfamily) [1-103]
- IPR050576: Ciliary and flagellar integrity-associated protein (family) [1-875]
- IPR001611: Leucine-rich repeat (repeat) [43-64]
- IPR001611: Leucine-rich repeat (repeat) [65-86]
- IPR025875: Leucine rich repeat 4 (repeat) [65-102]
- IPR001611: Leucine-rich repeat (repeat) [87-108]
- IPR032675: Leucine-rich repeat domain superfamily (homologous_superfamily) [104-204]
- IPR001611: Leucine-rich repeat (repeat) [111-132]
## GO Term Predictions
### Molecular Function
### Biological Process
### Cellular Component
Gene symbol: AGAP009594 (VectorBase), ortholog of human DNAAF1 (formerly LRRC50)
DNAAF1 (Dynein Axonemal Assembly Factor 1) is a leucine-rich repeat protein that functions as a cytoplasmic chaperone/assembly factor required for the preassembly of both outer dynein arms (ODA) and inner dynein arms (IDA) before their transport into the ciliary axoneme.
The protein was originally identified as LRRC50 (Leucine Rich Repeat Containing 50), and is the human ortholog of Chlamydomonas ODA7.
PMID:19944405 - Duquesnoy et al. (2009) "Loss-of-function mutations in the human ortholog of Chlamydomonas reinhardtii ODA7 disrupt dynein arm assembly and cause primary ciliary dyskinesia." Am J Hum Genet 85:890-896. Identified mutations in LRRC50 in four families with PCD. Demonstrated "a key role...in cytoplasmic preassembly of dynein arms."
PMID:19944400 - Loges et al. (2009) "Deletions and point mutations of LRRC50 cause primary ciliary dyskinesia due to dynein arm defects." Am J Hum Genet. Found LRRC50 mutations cause "combined defect involving assembly of the ODAs and IDAs." LRRC50 deficiency disrupts assembly of DNAH5/DNAI2-containing ODA complexes and DNALI1-containing IDA complexes, resulting in immotile cilia.
PMID:17194703 - Freshour et al. (2007) "Chlamydomonas flagellar outer row dynein assembly protein ODA7 interacts with both outer row and I1 inner row dyneins." J Biol Chem. Identified ODA7 gene product as "a 58-kDa leucine-rich repeat protein" that forms a structural link between inner and outer row dyneins on the doublet surface.
PMID:29228333 - Hartill et al. (2018) "DNAAF1 links heart laterality with the AAA+ ATPase RUVBL1 and ciliary intraflagellar transport." Hum Mol Genet 27:529-545. Identified DNAAF1 mutations causing congenital heart disease and PCD. Revealed interactions with IFT88 and RUVBL1 (Pontin). RUVBL1 shows asymmetric left-sided distribution at embryonic nodes dependent on DNAAF1.
PMID:18385425 - van Rooijen et al. (2008) "LRRC50, a Conserved Ciliary Protein Implicated in Polycystic Kidney Disease." JASN. Zebrafish lrrc50 mutants show pronephric cysts, disorganized pronephric cilia, and loss of ODA from outer-doublet microtubules. Human LRRC50 localizes to the ciliary structure.
DNAAF1/LRRC50 operates as part of a cytoplasmic dynein arm preassembly complex:
- Associates with AAA+ ATPases RUVBL1 (Pontin) and RUVBL2 (Reptin)
- Required for folding/assembly of dynein heavy chains and intermediate chains in the cytoplasm
- Associates with IFT-B complex (IFT88), coupling dynein arm assembly to ciliary transport PMID:29228333
- Loss of function results in absence of both ODA and IDA from axonemes
In mosquitoes, motile cilia/flagella are found in:
- Sperm flagella (critical for male fertility)
- Possibly sensory neurons (chordotonal organs)
The protein is 910 amino acids with 5 N-terminal leucine-rich repeats and an LRRCT domain, followed by a large C-terminal domain belonging to the ciliary/flagellar integrity family (IPR050576).
The BioReason deep-research report (bioreason-pro SFT) makes several claims that are problematic:
GO:0044877 protein-containing complex binding - Too generic. The existing annotation GO:0070840 (dynein complex binding) is far more specific and accurate. BioReason missed this obvious annotation.
GO:0008590 negative regulation of smoothened signaling pathway - This appears to come from the UniProt summary for Q7PK92 which states "Negatively regulates the Hedgehog (Hh) signaling pathway, possibly by regulating the activity of smoothened (smo)." However, this UniProt comment likely refers to a specific Drosophila study and may not reflect the core conserved function. The conserved function of DNAAF1 orthologs across all species is dynein arm assembly, not Hedgehog signaling. The Hedgehog connection is likely secondary to ciliary dysfunction (Hedgehog signaling depends on primary cilia in vertebrates, but this is not the core function of DNAAF1 as an assembly factor).
GO:0070373 negative regulation of ERK1 and ERK2 cascade - UNSUPPORTED. No literature connects DNAAF1/LRRC50 to ERK signaling. This appears to be a confabulation.
GO:0050848 regulation of calcium-mediated signaling - UNSUPPORTED. No literature connects DNAAF1 to calcium signaling.
GO:0008088 axo-dendritic transport - UNSUPPORTED. DNAAF1 is not involved in neuronal transport. This is a confabulation.
GO:0010628 positive regulation of gene expression - UNSUPPORTED. No evidence for this.
GO:0005737 cytoplasm - Correct. DNAAF1 is a cytoplasmic assembly factor. However, the existing annotations show it is also active in the axoneme (GO:0005930) and located in the cilium (GO:0005929).
Source: DNAAF1-deep-research-bioreason-sft.md
The BioReason SFT functional summary states:
A cytoplasmic leucine-rich repeat scaffold that assembles and positions large protein complexes to control signaling and transport. Its N-terminal repeat array provides a high-affinity docking surface that captures transport and signaling modules, while the extended scaffold stabilizes these assemblies to direct them toward the ciliary base and neuronal processes. Through spatial sequestration and delivery of components, it dampens Smoothened-dependent Hedgehog signaling, restrains ERK1/2 activation, modulates calcium-dependent signaling microdomains, and supports axo-dendritic cargo trafficking. These coordinated actions can ultimately enhance gene expression programs downstream of the tuned signaling outputs.
Strengths:
The summary correctly identifies DNAAF1 as a cytoplasmic leucine-rich repeat protein. This is consistent with the domain architecture (5 N-terminal LRRs, LRRCT domain) and the known cytoplasmic localization of DNAAF1 orthologs PMID:19944405.
The mention of assembling "large protein complexes" is partially correct in a very generic sense -- DNAAF1 does assemble dynein arm complexes. However, the summary never identifies dynein as the relevant complex.
The mention of the ciliary base is tangentially relevant, as DNAAF1-assembled dynein complexes are directed toward the cilium via intraflagellar transport PMID:29228333.
Weaknesses:
Fundamental misidentification of function. The summary describes DNAAF1 as a "signaling scaffold" that controls Hedgehog, ERK, calcium signaling, and gene expression. The actual conserved function of DNAAF1/LRRC50/ODA7 is well-established: it is a cytoplasmic dynein arm assembly factor required for preassembly of both outer and inner dynein arm complexes [PMID:19944405, PMID:19944400, PMID:17194703]. The BioReason model completely misses this core function.
GO:0008590 (negative regulation of smoothened signaling pathway) is misleading. The UniProt summary for Q7PK92 states "Negatively regulates the Hedgehog (Hh) signaling pathway, possibly by regulating the activity of smoothened (smo)." This appears to derive from a Drosophila screen and likely reflects an indirect consequence of ciliary dysfunction rather than a direct signaling role. In vertebrates, Hedgehog signaling depends on primary cilia, so loss of ciliary function secondarily disrupts Hedgehog signaling. The BioReason model treats this as a core function rather than recognizing it as a downstream consequence of the actual molecular function (dynein arm assembly). Critically, in Anopheles gambiae, there is no evidence that Hedgehog signaling depends on cilia as it does in vertebrates.
GO:0070373 (negative regulation of ERK1 and ERK2 cascade) is entirely fabricated. No published literature connects DNAAF1, LRRC50, or ODA7 to ERK/MAPK signaling in any organism. This is a confabulation generated by the language model.
GO:0050848 (regulation of calcium-mediated signaling) is entirely fabricated. No evidence connects DNAAF1 to calcium signaling.
GO:0008088 (axo-dendritic transport) is entirely fabricated. DNAAF1 is not involved in neuronal transport. This appears to result from the model incorrectly extrapolating from LRR domains and microtubule-associated functions to neuronal trafficking.
GO:0010628 (positive regulation of gene expression) is entirely fabricated. No evidence supports this annotation.
GO:0044877 (protein-containing complex binding) was predicted as the molecular function, but this is far too generic. The actual curated MF annotation is GO:0070840 (dynein complex binding), which is specific and well-supported. The model failed to identify the correct specific term.
All six existing GO annotations were missed. The curated annotations (dynein complex binding, axoneme assembly, cilium assembly, determination of left/right symmetry, axoneme, cilium) are well-supported by ortholog evidence. The BioReason model predicted none of them.
Scoring rationale:
Correctness (1/5): The model fundamentally mischaracterizes DNAAF1 as a signaling scaffold. Three of the six predicted GO terms (ERK regulation, calcium signaling, axo-dendritic transport) are entirely fabricated with no literature support. The Hedgehog signaling annotation is misleading when presented as a core function. Only the cytoplasm localization is unambiguously correct.
Completeness (1/5): None of the six existing curated GO annotations were identified. The core molecular function (dynein complex binding), the core biological process (axoneme assembly), and the primary localizations (axoneme, cilium) were all missed. The model does not mention dynein at all in its predictions, despite this being the defining function of the DNAAF1 protein family.
The InterPro domain IPR050576 (Ciliary and flagellar integrity-associated protein) covers nearly the entire protein (residues 1-875) and directly maps to ciliary function. A conservative InterPro2GO mapping from this domain would correctly predict cilium-related GO terms (cilium assembly, axoneme assembly). The LRR domains (IPR001611, IPR025875, IPR032675) would map to generic protein-protein interaction capabilities.
BioReason's output is actually worse than what a simple InterPro2GO mapping would produce:
- InterPro2GO from IPR050576 would correctly predict ciliary/flagellar function.
- BioReason ignored the ciliary/flagellar integrity family annotation and instead over-interpreted the LRR domains as generic signaling scaffolds.
- The BioReason model generated multiple fabricated signaling pathway annotations that InterPro2GO would never produce.
This is a case where the language model's tendency to generate plausible-sounding but unsupported functional narratives actively degrades prediction quality compared to a simple rule-based domain-to-function mapping.
The thinking trace demonstrates a systematic failure mode:
It correctly identifies the N-terminal LRR architecture and the IPR050576 (ciliary/flagellar integrity) family annotation.
However, instead of using the ciliary integrity family annotation to guide functional prediction toward the well-characterized dynein arm assembly role, the model treats the LRR domains as the primary functional determinant. It states: "This tandem arrangement of LRR units creates a curved solenoid surface optimized for high-affinity, sequence-specific protein docking rather than catalysis." This is generically true of LRR proteins but misses the specific biological context.
The trace then makes a critical error: it interprets "protein-containing complex binding" as the molecular function and spins an elaborate narrative about signaling scaffold activities (Hedgehog, ERK, calcium) and neuronal transport, none of which are supported by literature.
The UniProt summary mentioning Hedgehog/Smoothened regulation appears to have anchored the model toward signaling functions, when this annotation is likely a secondary consequence of ciliary dysfunction rather than the core molecular function.
The absence of any GO term predictions in the Molecular Function, Biological Process, or Cellular Component sections of the BioReason output (all three are blank) is notable -- the detailed predictions appear only in the thinking trace and functional summary, not in the structured output fields.
This case illustrates the danger of language model-based functional prediction when the model prioritizes narrative coherence over domain-specific biological knowledge. A domain expert would immediately recognize IPR050576 and the LRR architecture as hallmarks of the DNAAF family and predict dynein arm assembly as the core function.
id: Q7PK92
gene_symbol: DNAAF1
product_type: PROTEIN
status: DRAFT
taxon:
id: NCBITaxon:7165
label: Anopheles gambiae
description: >-
DNAAF1 (AGAP009594) is the Anopheles gambiae ortholog of human DNAAF1 (formerly
LRRC50) and Chlamydomonas ODA7. It is a cytoplasmic leucine-rich repeat protein
that functions as a dynein arm assembly factor, required for the preassembly of
both outer dynein arm (ODA) and inner dynein arm (IDA) complexes in the cytoplasm
before their transport into the ciliary/flagellar axoneme. The protein operates
as part of a chaperone complex with the AAA+ ATPases RUVBL1/RUVBL2 (Pontin/Reptin)
and couples dynein assembly to intraflagellar transport via interaction with IFT88.
Loss of function in orthologs across zebrafish, human, and Chlamydomonas results
in absence of both ODA and IDA from axonemes, immotile cilia/flagella, and primary
ciliary dyskinesia. In Anopheles gambiae, DNAAF1 is predicted to be essential for
sperm flagellar motility and potentially chordotonal organ function. All GO
annotations are inferred from orthologs by sequence similarity or phylogenetic
inference.
references:
- id: GO_REF:0000033
title: Annotation inferences using phylogenetic trees
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: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: PMID:19944405
title: Loss-of-function mutations in the human ortholog of Chlamydomonas reinhardtii
ODA7 disrupt dynein arm assembly and cause primary ciliary dyskinesia
findings:
- statement: LRRC50 mutations in four families cause PCD with absence of both
dynein arms, demonstrating a key role in cytoplasmic preassembly of dynein
arms.
supporting_text: support a key role for LRRC50, a member of the leucine-rich-repeat
superfamily, in cytoplasmic preassembly of dynein arms
reference_section_type: ABSTRACT
- id: PMID:19944400
title: Deletions and point mutations of LRRC50 cause primary ciliary dyskinesia
due to dynein arm defects
findings:
- statement: LRRC50 deficiency causes combined ODA and IDA defects, disrupting
assembly of DNAH5/DNAI2-containing ODA and DNALI1-containing IDA complexes.
supporting_text: combined defect involving assembly of the ODAs and IDAs
reference_section_type: ABSTRACT
- id: PMID:17194703
title: Chlamydomonas flagellar outer row dynein assembly protein ODA7 interacts
with both outer row and I1 inner row dyneins
findings:
- statement: ODA7 is a 58-kDa leucine-rich repeat protein that forms a structural
link between inner and outer row dyneins on the doublet surface.
supporting_text: Oda7 participates in a previously uncharacterized structural
link between inner and outer row dyneins
reference_section_type: ABSTRACT
- id: PMID:29228333
title: DNAAF1 links heart laterality with the AAA+ ATPase RUVBL1 and ciliary
intraflagellar transport
findings:
- statement: DNAAF1 interacts with IFT88 and RUVBL1, linking dynein arm
assembly to intraflagellar transport and heart laterality determination.
supporting_text: we identified interactions with members of a putative dynein
arm assembly complex. These include the ciliary intraflagellar transport
protein IFT88 and the AAA+...family proteins RUVBL1 (Pontin) and RUVBL2 (Reptin)
reference_section_type: ABSTRACT
- id: PMID:18385425
title: LRRC50, a Conserved Ciliary Protein Implicated in Polycystic Kidney Disease
findings:
- statement: Zebrafish lrrc50 mutants develop pronephric cysts with disorganized
cilia lacking outer dynein arms.
supporting_text: Electron microscopy analysis revealed ultrastructural
irregularities of the dynein arms and misalignments of the outer-doublet
microtubules on the ciliary axonemes
reference_section_type: ABSTRACT
- id: file:ANOGA/DNAAF1/DNAAF1-notes.md
title: Research notes on DNAAF1 in Anopheles gambiae
findings:
- statement: DNAAF1 orthologs are conserved dynein arm assembly factors across
eukaryotes from Chlamydomonas to human.
existing_annotations:
- term:
id: GO:0070840
label: dynein complex binding
evidence_type: ISS
original_reference_id: GO_REF:0000024
review:
summary: >-
Correct annotation. DNAAF1/LRRC50/ODA7 binds dynein complexes as its core
molecular function. The Chlamydomonas ortholog ODA7 interacts with both outer
row dynein and I1 inner row dynein. This binding is required for cytoplasmic
preassembly of dynein arm complexes.
action: ACCEPT
supported_by:
- reference_id: PMID:17194703
supporting_text: Oda7 participates in a previously uncharacterized structural
link between inner and outer row dyneins
- reference_id: file:ANOGA/DNAAF1/DNAAF1-deep-research-bioreason-sft.md
supporting_text: The BioReason report identifies IPR050576 (Ciliary and
flagellar integrity-associated protein family) covering the entire protein,
consistent with ciliary function
- term:
id: GO:0070840
label: dynein complex binding
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: >-
Redundant with the ISS annotation above. Both correctly capture the core
molecular function of dynein complex binding.
action: ACCEPT
supported_by:
- reference_id: PMID:17194703
supporting_text: Oda7 participates in a previously uncharacterized structural
link between inner and outer row dyneins
- term:
id: GO:0007368
label: determination of left/right symmetry
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: >-
This annotation reflects the role of DNAAF1 in left-right axis determination,
which depends on motile cilia at the embryonic node. DNAAF1 mutations in
humans cause situs inversus and congenital heart defects through loss of
nodal ciliary motility. However, determination of left/right symmetry is a
vertebrate-specific process involving nodal cilia, and its applicability to
Anopheles gambiae is questionable since insects do not use nodal cilia for
left-right patterning. This IBA annotation may be an over-extension of
vertebrate biology to an insect.
action: KEEP_AS_NON_CORE
reason: >-
Left-right symmetry determination via nodal cilia is a vertebrate mechanism.
While the IBA annotation from phylogenetic inference is technically valid,
this process is unlikely to occur in Anopheles gambiae which does not have
vertebrate-style nodal cilia. Kept as non-core rather than removed because
the phylogenetic inference is methodologically sound even if the biological
relevance to this species is uncertain.
supported_by:
- reference_id: PMID:29228333
supporting_text: DNAAF1-RUVBL1 biochemical and genetic interactions have a
novel functional role in symmetry breaking and cardiac development
- term:
id: GO:0035082
label: axoneme assembly
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: >-
Correct and core annotation. DNAAF1 is directly required for axoneme assembly
through its role in preassembling dynein arm complexes in the cytoplasm.
Loss of DNAAF1 orthologs results in axonemes lacking both outer and inner
dynein arms.
action: ACCEPT
supported_by:
- reference_id: PMID:19944400
supporting_text: combined defect involving assembly of the ODAs and IDAs
- term:
id: GO:0060271
label: cilium assembly
evidence_type: ISS
original_reference_id: GO_REF:0000024
review:
summary: >-
Appropriate annotation. DNAAF1 contributes to cilium assembly by enabling
the cytoplasmic preassembly of dynein arm complexes that are then transported
into the cilium. However, the more specific term GO:0035082 (axoneme assembly)
better captures the precise step at which DNAAF1 acts. DNAAF1 is not involved
in ciliogenesis per se (basal body formation, transition zone assembly) but
specifically in the assembly of dynein arms that are components of the axoneme.
action: KEEP_AS_NON_CORE
reason: >-
While cilium assembly is technically correct, DNAAF1 specifically acts at the
level of axoneme assembly (dynein arm preassembly). The more specific term
GO:0035082 is the core annotation. Cilium assembly is retained as non-core
because it is not incorrect, just less precise.
supported_by:
- reference_id: PMID:19944405
supporting_text: support a key role for LRRC50, a member of the leucine-rich-repeat
superfamily, in cytoplasmic preassembly of dynein arms
- term:
id: GO:0005930
label: axoneme
qualifier: is_active_in
evidence_type: IBA
original_reference_id: GO_REF:0000033
review:
summary: >-
The Chlamydomonas ortholog ODA7 is found associated with the axoneme where
it forms a structural link between inner and outer dynein arms. However,
DNAAF1 primarily functions in the cytoplasm as an assembly factor. The
axonemal localization may reflect the final destination of assembled dynein
complexes rather than the primary site of DNAAF1 activity.
action: KEEP_AS_NON_CORE
reason: >-
DNAAF1 primarily functions in the cytoplasm during dynein arm preassembly.
Some axonemal association is documented for the Chlamydomonas ortholog ODA7,
but the primary functional site is cytoplasmic. Kept as non-core.
supported_by:
- reference_id: PMID:17194703
supporting_text: Oda7 participates in a previously uncharacterized structural
link between inner and outer row dyneins
- term:
id: GO:0005930
label: axoneme
qualifier: located_in
evidence_type: ISS
original_reference_id: GO_REF:0000024
review:
summary: >-
Consistent with the IBA annotation above. DNAAF1/ODA7 has been found
associated with the axoneme in Chlamydomonas.
action: KEEP_AS_NON_CORE
reason: >-
The primary site of activity is the cytoplasm, but axonemal localization
is documented for the ortholog. Kept as non-core.
supported_by:
- reference_id: PMID:17194703
supporting_text: Oda7 participates in a previously uncharacterized structural
link between inner and outer row dyneins
- term:
id: GO:0005929
label: cilium
qualifier: located_in
evidence_type: IEA
original_reference_id: GO_REF:0000044
review:
summary: >-
Consistent with the axoneme localization. The cilium is the parent structure
containing the axoneme. LRRC50 has been localized to the ciliary structure
in zebrafish and human cells.
action: KEEP_AS_NON_CORE
reason: >-
Correct but less specific than the axoneme annotation. The primary functional
site is the cytoplasm.
supported_by:
- reference_id: PMID:18385425
supporting_text: Subcellular distribution of human LRRC50-EGFP in MDCK and
HEK293T cells is diffusely cytoplasmic and concentrated at the mitotic
spindle poles and cilium
- term:
id: GO:0005737
label: cytoplasm
qualifier: located_in
evidence_type: ISS
original_reference_id: PMID:18385425
review:
summary: >-
DNAAF1 primarily functions in the cytoplasm where it assembles dynein arm
complexes before their transport into the cilium. Human LRRC50-EGFP shows
diffuse cytoplasmic distribution. This is the primary site of DNAAF1 activity
as a dynein arm assembly factor.
action: NEW
reason: >-
The cytoplasmic localization is well-supported and represents the primary
functional site of DNAAF1, where dynein arm preassembly occurs. This
annotation is important because it distinguishes the assembly site
(cytoplasm) from the destination (axoneme/cilium).
supported_by:
- reference_id: PMID:18385425
supporting_text: Subcellular distribution of human LRRC50-EGFP in MDCK and
HEK293T cells is diffusely cytoplasmic and concentrated at the mitotic
spindle poles and cilium
core_functions:
- description: >-
Cytoplasmic dynein arm assembly factor that binds dynein complexes (both outer
and inner dynein arm subunits) and facilitates their preassembly in the
cytoplasm before transport into the ciliary/flagellar axoneme. Operates as part
of a chaperone complex with RUVBL1/RUVBL2 and couples assembled dynein arms to
intraflagellar transport via IFT88.
molecular_function:
id: GO:0070840
label: dynein complex binding
directly_involved_in:
- id: GO:0035082
label: axoneme assembly
locations:
- id: GO:0005737
label: cytoplasm
supported_by:
- reference_id: PMID:19944405
supporting_text: a key role...in cytoplasmic preassembly of dynein arms
- reference_id: PMID:17194703
supporting_text: Oda7 participates in a previously uncharacterized structural
link between inner and outer row dyneins
- reference_id: PMID:29228333
supporting_text: we identified interactions with members of a putative dynein
arm assembly complex. These include the ciliary intraflagellar transport
protein IFT88 and the AAA+...family proteins RUVBL1 (Pontin) and RUVBL2 (Reptin)
suggested_questions:
- question: >-
Does DNAAF1 in Anopheles gambiae function specifically in sperm flagellar
dynein assembly, and does its loss cause male sterility in mosquitoes?
- question: >-
Is the IBA annotation for left-right symmetry determination biologically
relevant in insects, or is this a vertebrate-specific function that should
not be transferred to Anopheles?
suggested_experiments:
- description: >-
CRISPR knockout of AGAP009594 (DNAAF1) in Anopheles gambiae to assess
effects on sperm flagellar motility and male fertility.
- description: >-
Transmission electron microscopy of sperm flagella in DNAAF1 knockdown
mosquitoes to determine whether outer and inner dynein arms are absent
from the axoneme, as observed in vertebrate orthologs.