CHMP1A
Description
The CHMP1A (charged multivesicular body protein 1A) is a protein-coding gene located on chromosome 16.
CHMP1A is a protein encoded by the CHMP1A gene in humans. It belongs to the CHMP/Chmp family, which plays a crucial role in the sorting of proteins to lysosomes via multivesicular bodies (MVBs). The initial prediction of CHMP1A's function suggested a metallopeptidase role, but recent findings have established its involvement in MVB sorting. CHMP1A interacts with VPS4A, and its function is critical for the formation and proper function of MVBs.
CHMP1A is a component of the ESCRT-III complex, which is essential for the formation of multivesicular bodies (MVBs). MVBs are responsible for sorting and delivering proteins to lysosomes for degradation. CHMP1A plays a role in the invagination and scission of the endosome membrane, forming intraluminal vesicles (ILVs) within MVBs. The ESCRT machinery operates in a sequential manner, with ESCRT-O, -I, -II, and -III complexes working together to achieve this process. CHMP1A detaches from the membrane before the ILV is released. Beyond its role in MVB biogenesis, CHMP1A is also involved in cytokinesis, recruiting VPS4A and/or VPS4B to the midbody of dividing cells. It may contribute to chromosome condensation and the silencing of Polycomb group (PcG) genes by targeting the BMI1/PCGF4 protein to condensed chromatin.
CHMP1A is also known as CHMP1, PCH8, PCOLN3, PRSM1, VPS46-1, VPS46A.