charged multivesicular body protein 1A; chromatin-modifying protein 1a; CHMP1a; vacuolar protein sorting-associated protein 46-1; Vps46-1; hVps46-1 (CHMP1A, CHMP1, KIAA0047, PCOLN3, PRSM1)

Function

• component of ESCRT3 in the multivesicular body pathway
• interaction with VPS4A & VPS4B mediates ATP-dependent disassembly of the ESCRT3
• self-associates
• interacts with CHMP1B, VPS4A, VPS4B, PHF1, IST1

Structure

belongs to the SNF7 family

Compartment

• cytoplasm, endosome
• endosomal membrane, peripheral membrane
• nuclear form remains associated with the chromosome scaffold during mitosis
• on overexpression,localizes to nuclear bodies characterized by nuclease-resistant condensed chromatin

Alternative splicing

named isoforms=2

Expression

• expressed in placenta, cultured skin, fibroblasts, osteoblast cell line MG63
• induced by muristerone

Notes

• originally thought to be a metalloprotease PRSM1, based on a wrong translation of the ORF
• procollagen-3 & CHMP1 are encoded by different ORFs in the PCOLN3 gene

More general terms

• charged multivesicular body protein (CHMP)

Component of

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

Database

• OMIM: https://mirror.omim.org/entry/164010
• UniProt: http://www.uniprot.org/uniprot/Q9HD42.html