CHMP1B

Existing Annotations Review

Gene Description

Existing Annotations Review

Core Functions

References

Deep Research

Falcon

Perplexity

📚 Additional Documentation

Notes

📄 View Raw YAML

GO Term	Evidence	Action	Reason
GO:0005771 multivesicular body	IBA GO_REF:0000033	ACCEPT	Summary: CHMP1B is a core ESCRT-III component that localizes to MVBs where it mediates intraluminal vesicle formation and cargo sorting. Reason: MVB localization is a core function of CHMP1B. The deep research extensively describes CHMP1B's role in MVB formation and ILV biogenesis with colocalization to late endosomal/MVB compartments marked by Lamp1. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md CHMP1B shows more robust colocalization with late endosomal markers including Lamp1, suggesting preferential recruitment to MVBs and late endosomal compartments where degradative cargo sorting occurs file:human/CHMP1B/CHMP1B-deep-research-falcon.md See deep research file for comprehensive analysis
GO:0015031 protein transport	IBA GO_REF:0000033	MODIFY	Summary: This term is overly broad and uninformative for CHMP1B's specific function. Should be replaced with more specific MVB cargo sorting and endosomal trafficking terms. Reason: While CHMP1B does participate in protein transport, this IBA annotation is too general. CHMP1B specifically mediates cargo sorting via MVB pathway and endosomal recycling, not general protein transport. Proposed replacements: endosome transport via multivesicular body sorting pathway multivesicular body sorting pathway
GO:0032509 endosome transport via multivesicular body sorting pathway	IBA GO_REF:0000033	ACCEPT	Summary: Core ESCRT-III function for CHMP1B in mediating cargo transport through the MVB pathway for lysosomal degradation. Reason: This IBA correctly captures CHMP1B's central role in the MVB sorting pathway. Literature extensively documents CHMP1B's function in cargo sorting and ILV formation. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md The primary established function of CHMP1B derives from its participation in multivesicular body (MVB) formation, a critical process in which cargo-containing membrane invaginations at the limiting membrane of late endosomal compartments undergo scission to generate intraluminal vesicles (ILVs)
GO:0045324 late endosome to vacuole transport	IBA GO_REF:0000033	MODIFY	Summary: This term uses yeast-specific terminology. In mammals CHMP1B mediates late endosome to lysosome transport. Reason: The term uses "vacuole" which is yeast-specific nomenclature. For human CHMP1B, the equivalent process is late endosome to lysosome transport (GO:1902774), which is also annotated. Proposed replacements: late endosome to lysosome transport
GO:0000815 ESCRT III complex	IBA GO_REF:0000033	ACCEPT	Summary: CHMP1B is a core structural component of the ESCRT-III complex. This is fundamental to all CHMP1B functions. Reason: CHMP1B is definitionally an ESCRT-III component belonging to the SNF7 family. This is supported by extensive structural and functional evidence. Supporting Evidence: file:human/CHMP1B/CHMP1B-uniprot.txt Probable peripherally associated component of the endosomal sorting required for transport complex III (ESCRT-III) file:human/CHMP1B/CHMP1B-deep-research-perplexity.md Within the ESCRT-III complex, CHMP1B belongs to the CHMP1 subfamily, which includes the related protein CHMP1A and exhibits distinct functional properties compared to other ESCRT-III members such as the CHMP2, CHMP3, and CHMP4 families
GO:0000776 kinetochore	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: IEA annotation supported by experimental IDA evidence (PMID:26040712). Valid but non-core mitotic localization. Reason: Although there is direct experimental evidence (IDA) from PMID:26040712 showing CHMP1B localization to kinetochores during mitosis, this represents a non-core pleiotropic function, not the primary ESCRT-III role.
GO:0001778 plasma membrane repair	IEA GO_REF:0000117	ACCEPT	Summary: IEA annotation but supported by experimental evidence PMID:24482116 showing ESCRT machinery requirement for plasma membrane repair. Reason: Despite being IEA, this is supported by IDA evidence from PMID:24482116. The deep research confirms ESCRT machinery including CHMP1B is required for plasma membrane repair. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md CHMP1B exhibits predominantly cytoplasmic distribution under steady-state conditions
GO:0005643 nuclear pore	IEA GO_REF:0000117	ACCEPT	Summary: IEA annotation supported by experimental IDA evidence (PMID:26040713) for nuclear envelope reformation. Reason: This IEA is backed by IDA evidence showing CHMP1B involvement in nuclear membrane reassembly and nuclear pore function during cell division.
GO:0005765 lysosomal membrane	IEA GO_REF:0000117	ACCEPT	Summary: IEA annotation supported by IDA evidence (PMID:17984323). CHMP1B localizes to lysosomal membranes during autophagy and MVB-lysosome fusion. Reason: Supported by experimental evidence showing CHMP1B at lysosomal membranes, consistent with its role in MVB-lysosome fusion and autophagosome maturation.
GO:0005768 endosome	IEA GO_REF:0000044	MODIFY	Summary: Broad endosomal localization term. CHMP1B localizes more specifically to late endosomes and MVBs rather than generic endosomes. Reason: While technically correct, this term is too broad. CHMP1B specifically localizes to late endosomes and MVBs, not early endosomes. More specific terms like late endosome membrane (GO:0031902) or MVB membrane (GO:0032585) are more appropriate. Proposed replacements: late endosome membrane multivesicular body membrane
GO:0005828 kinetochore microtubule	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: IEA annotation supported by IDA evidence (PMID:26040712) during mitosis. Reason: Experimental evidence supports this localization during mitotic spindle disassembly and chromosome alignment, but this represents a non-core mitotic function, not the primary ESCRT-III role.
GO:0005829 cytosol	IEA GO_REF:0000044	ACCEPT	Summary: CHMP1B exists in cytosol in its autoinhibited monomeric form before membrane recruitment. Reason: Correct - CHMP1B exists as soluble cytosolic protein in autoinhibited state before activation and membrane recruitment. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md CHMP1B exhibits predominantly cytoplasmic distribution under steady-state conditions, where it exists in a monomeric, autoinhibited conformation
GO:0007034 vacuolar transport	IEA GO_REF:0000002	REMOVE	Summary: Yeast-specific term not appropriate for human CHMP1B. The mammalian equivalent is lysosomal transport. Reason: This term is based on InterPro domain annotation but uses yeast-specific vocabulary ("vacuolar"). For human CHMP1B, lysosomal/endosomal transport terms are more appropriate.
GO:0007080 mitotic metaphase chromosome alignment	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: IEA annotation supported by experimental IMP evidence (PMID:20616062). Reason: Experimental evidence supports this function, but it represents a non-core pleiotropic role. CHMP1B's primary function is membrane remodeling; chromosome alignment is a secondary consequence of its mitotic roles.
GO:0015031 protein transport	IEA GO_REF:0000043	MODIFY	Summary: Duplicate broad term based on UniProtKB keyword. Too general. Reason: This is a duplicate annotation (also present as IBA) and is overly broad. CHMP1B's transport functions are specific to MVB cargo sorting and endosomal trafficking. Proposed replacements: multivesicular body sorting pathway
GO:0030496 midbody	IEA GO_REF:0000117	ACCEPT	Summary: Midbody localization during cytokinesis is well-established and represents a core CHMP1B function for spastin recruitment. Reason: Multiple experimental evidences (IDA) confirm midbody localization where CHMP1B recruits spastin for abscission. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md CHMP1B undergoes striking relocalization to the midbody during cytokinesis, the final stage of cell division wherein dividing cells remain connected by a membrane bridge containing concentrated microtubules. CHMP1B localizes prominently to midbodies in dividing HeLa cells, where it colocalizes with the microtubule-severing protein spastin and other ESCRT components including CHMP5
GO:0031468 nuclear membrane reassembly	IEA GO_REF:0000117	ACCEPT	Summary: IEA annotation supported by experimental IMP evidence (PMID:26040713). Reason: Experimental evidence demonstrates CHMP1B's role in nuclear envelope reformation after mitosis via ESCRT-III-mediated membrane sealing.
GO:0031902 late endosome membrane	IEA GO_REF:0000044	ACCEPT	Summary: Late endosome membrane is a core localization site for CHMP1B during MVB cargo sorting. Reason: Correct localization - CHMP1B preferentially localizes to late endosomal membranes for MVB formation. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md CHMP1B shows more robust colocalization with late endosomal markers including Lamp1, suggesting preferential recruitment to MVBs and late endosomal compartments where degradative cargo sorting occurs
GO:0032585 multivesicular body membrane	IEA GO_REF:0000117	ACCEPT	Summary: Core localization site where CHMP1B mediates ILV formation. Reason: MVB membrane is a central localization for CHMP1B function. Extensively supported by experimental IDA evidence.
GO:0039702 viral budding via host ESCRT complex	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: CHMP1B has a moderate role in HIV-1 budding, less essential than CHMP2/CHMP4 family members. Reason: CHMP1B does participate in viral budding but with lower essentiality (8-fold reduction) compared to CHMP2/CHMP4 (95-166 fold). This is a valid but non-core function. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md Co-depletion of CHMP1A and CHMP1B reduced HIV-1 virus release modestly (>2-fold), whereas co-depletion of CHMP2A and CHMP2B or CHMP4A, CHMP4B, and CHMP4C produced dramatically more severe defects (95-fold and 166-fold reductions respectively). Individual CHMP1B depletion reduced viral titers 8-fold, making it a moderate contributor to HIV budding
GO:0043162 ubiquitin-dependent protein catabolic process via the multivesicular body sorting pathway	IEA GO_REF:0000117	ACCEPT	Summary: Core CHMP1B function in sorting ubiquitinated cargo into ILVs for lysosomal degradation. Reason: This precisely describes CHMP1B's central role in the MVB pathway for degrading ubiquitinated membrane proteins like activated receptor tyrosine kinases. Supporting Evidence: file:human/CHMP1B/CHMP1B-deep-research-perplexity.md The involvement of CHMP1B in this process is particularly important for trafficking of ubiquitinated cargo destined for lysosomal degradation
GO:0046761 viral budding from plasma membrane	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: Related to CHMP1B's role in HIV-1 release via ESCRT machinery. Reason: CHMP1B contributes to HIV budding but it is not a core function - more of an accessory role compared to other ESCRT-III proteins.
GO:0051301 cell division	IEA GO_REF:0000043	MODIFY	Summary: CHMP1B participates in cytokinetic abscission which is part of cell division, but this term is too broad. Reason: While CHMP1B does function in cell division, the more specific term "midbody abscission" (GO:0061952) better captures its precise role. Proposed replacements: midbody abscission
GO:0061952 midbody abscission	IEA GO_REF:0000117	ACCEPT	Summary: CHMP1B recruits spastin to midbodies for cytokinetic abscission - a well-established core function. Reason: Well-supported by experimental evidence showing CHMP1B's essential role in recruiting spastin for membrane scission during cytokinesis. Supporting Evidence: file:human/CHMP1B/CHMP1B-uniprot.txt Involved in cytokinesis. Involved in recruiting VPS4A and/or VPS4B and SPAST to the midbody of dividing cells
GO:0071985 multivesicular body sorting pathway	IEA GO_REF:0000117	ACCEPT	Summary: Core pathway for CHMP1B function in cargo sorting and ILV biogenesis. Reason: Central to CHMP1B's primary function. Well-supported by experimental evidence.
GO:0097352 autophagosome maturation	IEA GO_REF:0000117	ACCEPT	Summary: CHMP1B is required for fusion of autophagosomes with lysosomes during autophagy. Reason: Experimental evidence (IMP PMID:17984323) demonstrates CHMP1B's requirement for autophagosome maturation and clearance of protein aggregates. Supporting Evidence: file:human/CHMP1B/CHMP1B-uniprot.txt Functional multivesicular bodies are required for autophagic clearance of protein aggregates
GO:1901673 regulation of mitotic spindle assembly	IEA GO_REF:0000117	KEEP AS NON CORE	Summary: Non-core pleiotropic function during mitosis. Reason: Experimental evidence supports this but it represents a secondary mitotic role, not core ESCRT-III function.
GO:1902774 late endosome to lysosome transport	IEA GO_REF:0000117	ACCEPT	Summary: Core CHMP1B function in MVB-lysosome fusion for cargo degradation. Reason: This correctly describes CHMP1B's role in mediating fusion of MVBs with lysosomes to enable degradation of sorted cargo.
GO:1904930 amphisome membrane	IEA GO_REF:0000117	ACCEPT	Summary: Amphisomes are hybrid organelles formed by fusion of autophagosomes with endosomes. Valid localization. Reason: Supported by experimental IDA evidence (PMID:17984323) in context of autophagy.
GO:0005515 protein binding	IPI PMID:16730941 A systematic analysis of human CHMP protein interactions: ad...	MODIFY	Summary: Generic protein binding term - uninformative. Actual interactions include CHMP1A, STAMBP, VPS4A. Reason: This generic term doesn't provide useful information about CHMP1B function. The paper identifies specific binding partners. More specific terms like "MIT domain binding" or "identical protein binding" are more informative. Proposed replacements: identical protein binding MIT domain binding Supporting Evidence: PMID:16730941 May 30. A systematic analysis of human CHMP protein interactions: additional MIT domain-containing proteins bind to multiple components of the human ESCRT III complex.
GO:0005515 protein binding	IPI PMID:17711858 The MIT domain of UBPY constitutes a CHMP binding and endoso...	MODIFY	Summary: Generic protein binding - this paper shows UBPY/USP8 binding to CHMP1B. Should use more specific term. Reason: Paper demonstrates USP8 deubiquitinase binding to CHMP1B via MIT domain. More informative to annotate as MIT domain binding. Proposed replacements: MIT domain binding Supporting Evidence: PMID:17711858 2007 Aug 21. The MIT domain of UBPY constitutes a CHMP binding and endosomal localization signal required for efficient epidermal growth factor receptor degradation.
GO:0005515 protein binding	IPI PMID:17928862 ESCRT-III recognition by VPS4 ATPases	MODIFY	Summary: Generic term - paper shows VPS4 ATPase binding via MIT-MIM interaction. Reason: This paper characterizes ESCRT-III recognition by VPS4 MIT domains. MIT domain binding is more specific. Proposed replacements: MIT domain binding Supporting Evidence: PMID:17928862 ESCRT-III recognition by VPS4 ATPases.
GO:0005515 protein binding	IPI PMID:19302785 Ab initio protein modelling reveals novel human MIT domains	MODIFY	Summary: Generic protein binding for USP8 interaction. Should be MIT domain binding. Reason: Paper identifies MIT domains including USP8 binding to CHMP1B. Proposed replacements: MIT domain binding Supporting Evidence: PMID:19302785 2009 Feb 12. Ab initio protein modelling reveals novel human MIT domains.
GO:0005515 protein binding	IPI PMID:19525971 Structural basis for ESCRT-III protein autoinhibition	ACCEPT	Summary: Paper on ESCRT-III autoinhibition showing IST1 and CHMP1B binding. Generic term uninformative. Reason: Keep this as evidence of IST1-CHMP1B interaction which is critical for copolymer formation, though generic. Supporting Evidence: PMID:19525971 Jun 14. Structural basis for ESCRT-III protein autoinhibition.
GO:0005515 protein binding	IPI PMID:21827950 Structural basis for ESCRT-III CHMP3 recruitment of AMSH	ACCEPT	Summary: Generic term for STAMBP/AMSH recruitment to CHMP1B. Reason: Documents important CHMP1B-STAMBP interaction though term is generic. Supporting Evidence: PMID:21827950 Structural basis for ESCRT-III CHMP3 recruitment of AMSH.
GO:0005515 protein binding	IPI PMID:21988832 Toward an understanding of the protein interaction network o...	ACCEPT	Summary: Large-scale liver interactome study with STAMBP interaction. Reason: Large-scale proteomic evidence for interactions, keep as supporting evidence. Supporting Evidence: PMID:21988832 Toward an understanding of the protein interaction network of the human liver.
GO:0005515 protein binding	IPI PMID:25416956 A proteome-scale map of the human interactome network	ACCEPT	Summary: Large-scale human interactome with STAMBP. Reason: Large-scale proteomic data supporting protein interactions. Supporting Evidence: PMID:25416956 A proteome-scale map of the human interactome network.
GO:0005515 protein binding	IPI PMID:26634441 Structure and membrane remodeling activity of ESCRT-III heli...	ACCEPT	Summary: ESCRT-III helical polymer structure showing IST1 binding. Reason: Critical structural paper on IST1-CHMP1B copolymers. Supporting Evidence: PMID:26634441 2015 Dec 3. Structure and membrane remodeling activity of ESCRT-III helical polymers.
GO:0005515 protein binding	IPI PMID:31515488 Extensive disruption of protein interactions by genetic vari...	ACCEPT	Summary: Genetic variants affecting protein interactions with STAMBP. Reason: Evidence for CHMP1B-STAMBP interaction. Supporting Evidence: PMID:31515488 Extensive disruption of protein interactions by genetic variants across the allele frequency spectrum in human populations.
GO:0005515 protein binding	IPI PMID:32296183 A reference map of the human binary protein interactome	ACCEPT	Summary: Binary protein interactome with STAMBP, MITD1, VTA1, PICK1. Reason: Large-scale systematic interaction data. Supporting Evidence: PMID:32296183 Apr 8. A reference map of the human binary protein interactome.