VPS33B

Description

The VPS33B (VPS33B late endosome and lysosome associated) is a protein-coding gene located on chromosome 15.

Vacuolar protein sorting-associated protein 33B is a protein encoded by the VPS33B gene in humans. It is involved in vesicle-mediated protein sorting, a crucial process for segregating intracellular molecules into different organelles. This gene belongs to the Sec-1 domain family and is the human counterpart of rat Vps33b, which shares homology with the yeast class C Vps33 protein. The mammalian class C Vps proteins primarily reside in late endosomes/lysosomes and, like their yeast counterparts, may be involved in vesicle trafficking steps within the endosome/lysosome pathway.

VPS33B plays a key role in vesicle-mediated protein transport to lysosomes, influencing membrane docking and fusion events within late endosomes/lysosomes. It is essential for the correct trafficking and localization of lysyl hydroxylase 3 (LH3), an enzyme that modifies collagen, to intracellular collagen. VPS33B mediates phagolysosomal fusion in macrophages, suggesting its involvement in immune responses. In association with VIPAS39, VPS33B contributes to endosomal maturation and regulates the apical recycling pathway in epithelial cells, maintaining apical-basolateral polarity. It also appears to participate in the sorting of specific cargos from the trans-Golgi network to alpha-granule-destined multivesicular bodies (MVBs) in megakaryocytes, promoting MVB maturation. VPS33B interacts with RAB11A, VIPAS39, and RAB25, and associates with adapter protein complex 3 (AP-3), clathrin:AP-3, and clathrin:HGS complexes, highlighting its involvement in diverse protein sorting and trafficking pathways. VPS33B also interacts with M.tuberculosis PtpA, suggesting a role in microbial infection.

VPS33B is also known as KDIDAR, PFIC12.

Associated Diseases

WES Whole Exome Sequencing

Clinical Exome Sequencing