charged multivesicular body protein 2A; chromatin-modifying protein 2a; CHMP2a; breast adenocarcinoma marker BC-2; vacuolar protein sorting-associated protein 2-1; Vps2-1; hVps2-1 (CHMP2A, BC2, CHMP2)

Function

• component of ESCRT3 in the multivesicular body pathway
• in the ESCRT3 complex, it interacts directly with CHMP3 & CHMP4A
• mediates ATP-dependent disassembly of ESCRT3 via interaction with VPS4A & VPS4B
• in vitro, heteromerizes with CHMP3 (but not CHMP4) to form helical tubular structures that expose membrane-interacting sites on the outside whereas VPS4B can associate on the inside of the tubule
• interacts with CHMP1B, CHMP2B, CHMP3, CHMP4A, CHMP4B, CHMP4C & CHMP5
• interacts with MITD1
• interacts with VTA1
  • interaction probably involves the open conformation of CHMP2A

Structure

• the acidic C-terminus & the basic N-termminus are thought to render the protein in a closed, soluble & inactive conformation through an autoinhibitory intramolecular interaction
• the open & active conformation, which enables membrane binding & oligomerization, is facilitate by interaction with other ESCRT components
• belongs to the SNF7 family

Compartment

• late endosome membrane
• peripheral membrane, cytoplasmic side
• localizes to the midbody of dividing cells
• localized in two distinct rings on either side of the midbody

Pathology

• overexpression strongly inhibits HIV-1 release (HIV-1 highjacks ESCRT3 for budding & exocytosis of viral proteins)

More general terms

• charged multivesicular body protein (CHMP)
• phosphoprotein

Component of

• endosomal sorting complex required for transport-3 (ESCRT3)

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=27243
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:27243
• OMIM: https://mirror.omim.org/entry/610893
• UniProt: http://www.uniprot.org/uniprot/O43633.html