InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: CHMP1A

Summary

InnateDB Protein

IDBP-234334.6

Last Modified

2014-10-13 [Report errors or provide feedback]

Gene Symbol

CHMP1A

Protein Name

charged multivesicular body protein 1A

Synonyms

CHMP1; PCH8; PCOLN3; PRSM1; VPS46-1; VPS46A;

Species

Homo sapiens

Ensembl Protein

ENSP00000380998

InnateDB Gene

IDBG-47864 (CHMP1A)

Protein Structure

UniProt Annotation

Function

Probable peripherally associated component of the endosomal sorting required for transport complex III (ESCRT-III) which is involved in multivesicular bodies (MVBs) formation and sorting of endosomal cargo proteins into MVBs. MVBs contain intraluminal vesicles (ILVs) that are generated by invagination and scission from the limiting membrane of the endosome and mostly are delivered to lysosomes enabling degradation of membrane proteins, such as stimulated growth factor receptors, lysosomal enzymes and lipids. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. ESCRT- III proteins mostly dissociate from the invaginating membrane before the ILV is released. The ESCRT machinery also functions in topologically equivalent membrane fission events, such as the terminal stages of cytokinesis and the budding of enveloped viruses (HIV-1 and other lentiviruses). ESCRT-III proteins are believed to mediate the necessary vesicle extrusion and/or membrane fission activities, possibly in conjunction with the AAA ATPase VPS4. Involved in cytokinesis. Involved in recruiting VPS4A and/or VPS4B to the midbody of dividing cells. May also be involved in chromosome condensation. Targets the Polycomb group (PcG) protein BMI1/PCGF4 to regions of condensed chromatin. May play a role in stable cell cycle progression and in PcG gene silencing. {ECO:0000269PubMed:11559747, ECO:0000269PubMed:11559748, ECO:0000269PubMed:19129479, ECO:0000269PubMed:23045692}.

Subcellular Localization

Cytoplasm. Endosome membrane; Peripheral membrane protein. Nucleus matrix. Note=The cytoplasmic form is partially membrane-associated and localizes to early endosomes. The nuclear form remains associated with the chromosome scaffold during mitosis. On overexpression, it localizes to nuclear bodies characterized by nuclease-resistant condensed chromatin.

Disease Associations

Pontocerebellar hypoplasia 8 (PCH8) [MIM:614961]: An autosomal recessive neurodevelopmental disorder characterized by severe psychomotor retardation, abnormal movements, hypotonia, spasticity, and variable visual defects. Brain MRI shows pontocerebellar hypoplasia, decreased cerebral white matter, and a thin corpus callosum. {ECO:0000269PubMed:23023333}. Note=The disease is caused by mutations affecting the gene represented in this entry.

Tissue Specificity

Expressed in placenta, cultured skin fibroblasts and in osteoblast cell line MG-63. {ECO:0000269PubMed:8863740}.

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 18 experimentally validated interaction(s) in this database.

Experimentally validated
Total	18 [view]
Protein-Protein	18 [view]
Protein-DNA	0
Protein-RNA	0
DNA-DNA	0
RNA-RNA	0
DNA-RNA	0

Gene Ontology

Molecular Function

Accession	GO Term
GO:0005515	protein binding
GO:0008237	metallopeptidase activity
GO:0008270	zinc ion binding
GO:0019904	protein domain specific binding
GO:0042803	protein homodimerization activity

Biological Process

GO:0000910	cytokinesis
GO:0006351	transcription, DNA-templated
GO:0006508	proteolysis
GO:0007034	vacuolar transport
GO:0007076	mitotic chromosome condensation
GO:0015031	protein transport
GO:0016192	vesicle-mediated transport
GO:0016458	gene silencing
GO:0045014	negative regulation of transcription by glucose
GO:0045892	negative regulation of transcription, DNA-templated

Cellular Component

GO:0000794	condensed nuclear chromosome
GO:0005769	early endosome
GO:0005815	microtubule organizing center
GO:0010008	endosome membrane
GO:0012505	endomembrane system
GO:0016363	nuclear matrix
GO:0070062	extracellular vesicular exosome