InnateDB: Systems Biology of the Innate Immune Response

Homo sapiens Protein: CHMP4A

Summary

InnateDB Protein

IDBP-3677.6

Last Modified

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

Gene Symbol

CHMP4A

Protein Name

Charged multivesicular body protein 4a

Synonyms

Species

Homo sapiens

Ensembl Protein

ENSP00000324205

InnateDB Gene

IDBG-547484 (CHMP4A)

Protein Structure

UniProt Annotation

Function

Probable core 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. When overexpressed, membrane-assembled circular arrays of CHMP4A filaments can promote or stabilize negative curvature and outward budding. Via its interaction with PDCD6IP involved in HIV-1 p6- and p9-dependent virus release. {ECO:0000269PubMed:12860994, ECO:0000269PubMed:14505569, ECO:0000269PubMed:14519844, ECO:0000269PubMed:14583093, ECO:0000269PubMed:18209100}.

Subcellular Localization

Cytoplasmic vesicle membrane. Late endosome membrane {ECO:0000305}; Peripheral membrane protein {ECO:0000305}. Note=Membrane-associated. Localizes to large vesicle-like structures. Localizes to the midbody of dividing cells. Localized in two distinct rings on either side of the Fleming body.

Disease Associations

Tissue Specificity

Widely expressed. Expressed at higher level in heart, kidney, liver and skeletal muscle. Also expressed in brain, placenta, lung and pancreas. {ECO:0000269PubMed:14678797}.

Comments

Interactions

Number of Interactions

This gene and/or its encoded proteins are associated with 30 experimentally validated interaction(s) in this database.

Experimentally validated
Total	30 [view]
Protein-Protein	30 [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:0008289	lipid binding
GO:0042802	identical protein binding
GO:0042803	protein homodimerization activity
GO:0051117	ATPase binding

Biological Process

GO:0006620	posttranslational protein targeting to membrane
GO:0006900	membrane budding
GO:0007034	vacuolar transport
GO:0015031	protein transport
GO:0016032	viral process
GO:0016197	endosomal transport
GO:0019058	viral life cycle
GO:0051260	protein homooligomerization
GO:0061024	membrane organization
GO:0097320	membrane tubulation
GO:1901215	negative regulation of neuron death
GO:1902902	negative regulation of autophagic vacuole assembly

Cellular Component

GO:0000815	ESCRT III complex
GO:0005634	nucleus
GO:0005737	cytoplasm
GO:0005829	cytosol
GO:0009898	cytoplasmic side of plasma membrane
GO:0030496	midbody
GO:0030659	cytoplasmic vesicle membrane
GO:0031902	late endosome membrane
GO:0070062	extracellular vesicular exosome