Q5R658 · VPS4B_PONAB
- ProteinVacuolar protein sorting-associated protein 4B
- GeneVPS4B
- StatusUniProtKB reviewed (Swiss-Prot)
- Amino acids444 (go to sequence)
- Protein existenceEvidence at transcript level
- Annotation score4/5
Function
function
Involved in late steps of the endosomal multivesicular bodies (MVB) pathway. Recognizes membrane-associated ESCRT-III assemblies and catalyzes their disassembly, possibly in combination with membrane fission. Redistributes the ESCRT-III components to the cytoplasm for further rounds of MVB sorting. 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. VPS4A/B are required for the exosomal release of SDCBP, CD63 and syndecan (By similarity).
(Microbial infection) In conjunction with the ESCRT machinery also appears to function in topologically equivalent membrane fission events, such as the terminal stages of cytokinesis and enveloped virus budding (lentiviruses).
Catalytic activity
- ATP + H2O = ADP + phosphate + H+
Features
Showing features for binding site.
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | late endosome membrane | |
Molecular Function | ATP binding | |
Molecular Function | ATP hydrolysis activity | |
Biological Process | cell division | |
Biological Process | endosomal transport | |
Biological Process | protein transport | |
Biological Process | vacuole organization |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended nameVacuolar protein sorting-associated protein 4B
- EC number
Gene names
Organism names
- Taxonomic lineageEukaryota > Metazoa > Chordata > Craniata > Vertebrata > Euteleostomi > Mammalia > Eutheria > Euarchontoglires > Primates > Haplorrhini > Catarrhini > Hominidae > Pongo
Accessions
- Primary accessionQ5R658
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Late endosome membrane ; Peripheral membrane protein
Note: Membrane-associated in the prevacuolar endosomal compartment.
Keywords
- Cellular component
PTM/Processing
Features
Showing features for chain, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000331379 | 1-444 | Vacuolar protein sorting-associated protein 4B | |||
Sequence: MSSTSPNLQKAIDLASKAAQEDKAGNYEEALQLYQHAVQYFLHVVKYEAQGDKAKQSIRAQCTEYLDRAEKLKEYLKNKEKKAQKPVKEGQPSPADEKGNDSDGEGESDDPEKKKLQNQLQGAIVIERPNVKWSDVAGLEGAKEALKEAVILPIKFPHLFTGKRTPWRGILLFGPPGTGKSYLAKAVATEANNSTFFSISSSDLVSKWLGESEKLVKNLFQLARENKPSIIFIDEIDSLCGSRSENESEAARRIKTEFLVQMRGVGVDNDGILVLGATNIPWVLDSAIRRRFEKRIYIPLPEPHARAAMFKLHLGTTQNSLTEADFRELGRKTDGYSGADISIIVRDALMQPVRKVQSATHFKKVRGPSRADPNHLVDDLLTPCSPGDPGAIEMTWMDVPGDKLLEPVVSMSDMLRSLSNTKPTVNEHDLLKLKKFTEDFGQEG | ||||||
Modified residue | 93 | Phosphoserine | ||||
Sequence: S | ||||||
Modified residue | 102 | Phosphoserine | ||||
Sequence: S | ||||||
Modified residue | 108 | Phosphoserine | ||||
Sequence: S | ||||||
Modified residue | 410 | Phosphoserine | ||||
Sequence: S |
Keywords
- PTM
Interaction
Subunit
Proposed to be monomeric or homodimeric in nucleotide-free form and to oligomerize upon binding to ATP to form two stacked hexameric or heptameric rings with a central pore through which ESCRT-III substrates are translocated in an ATP-dependent manner. In vitro, associates on the inside of a helical tubular structure formed by a CHMP2A-CHMP3 polymer. Interacts with CHMP1A, CHMP1B, CHMP2A, CHMP4B and CHMP6. Interacts with VPS4A; the interaction suggests a heteromeric assembly with VPS4A. Interacts with VTA1 (By similarity).
Protein-protein interaction databases
Structure
Family & Domains
Features
Showing features for domain, coiled coil, compositional bias, region.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 4-82 | MIT | ||||
Sequence: TSPNLQKAIDLASKAAQEDKAGNYEEALQLYQHAVQYFLHVVKYEAQGDKAKQSIRAQCTEYLDRAEKLKEYLKNKEKK | ||||||
Coiled coil | 19-82 | |||||
Sequence: AQEDKAGNYEEALQLYQHAVQYFLHVVKYEAQGDKAKQSIRAQCTEYLDRAEKLKEYLKNKEKK | ||||||
Compositional bias | 78-116 | Basic and acidic residues | ||||
Sequence: NKEKKAQKPVKEGQPSPADEKGNDSDGEGESDDPEKKKL | ||||||
Region | 78-117 | Disordered | ||||
Sequence: NKEKKAQKPVKEGQPSPADEKGNDSDGEGESDDPEKKKLQ |
Domain
The MIT domain serves as an adapter for ESCRT-III proteins. It forms an asymmetric three-helix bundle that binds amphipathic MIM (MIT interacting motif) helices along the groove between MIT helices 2 and 3 present in a subset of ESCRT-III proteins thus establishing the canonical MIM-MIT interaction. In an extended conformation along the groove between helices 1 and 3, also binds to a type-2 MIT interacting motif (MIM2).
Sequence similarities
Belongs to the AAA ATPase family.
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length444
- Mass (Da)49,330
- Last updated2004-12-21 v1
- ChecksumB6549F4E19C210F4
Features
Showing features for compositional bias.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Compositional bias | 78-116 | Basic and acidic residues | ||||
Sequence: NKEKKAQKPVKEGQPSPADEKGNDSDGEGESDDPEKKKL |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
CR860638 EMBL· GenBank· DDBJ | CAH92758.1 EMBL· GenBank· DDBJ | mRNA |