GP78 Antibody – Rabbit Polyclonal

This locus encodes a glycosylated transmembrane receptor. Its ligand, autocrine motility factor, is a tumor motility-stimulating protein secreted by tumor cells. The encoded receptor is also a member of the E3 ubiquitin ligase family of proteins. It catalyzes ubiquitination and endoplasmic reticulum-associated degradation of specific proteins. [provided by RefSeq, Feb 2012]

AMFR: E3 ubiquitin-protein ligase that mediates the polyubiquitination of a number of proteins such as CD3D, CYP3A4, CFTR and APOB for proteasomal degradation. Component of a VCP/p97- AMFR/gp78 complex that participates in the final step of endoplasmic reticulum-associated degradation (ERAD). The VCP/p97- AMFR/gp78 complex is involved in the sterol-accelerated ERAD degradation of HMGCR through binding to the HMGCR-INSIG complex at the ER membrane and initiating ubiquitination of HMGCR. The ubiquitinated HMGCR is then released from the ER by the complex into the cytosol for subsequent destruction. Also acts as a scaffold protein to assemble a complex that couples ubiquitination, retranslocation and deglycosylation. Mediates tumor invasion and metastasis. Interacts with RNF5. Also forms an ERAD complex containing VCP/p97, NGLY1; PSMC1; SAKS1 AND RAD23B required for coupling retrotranslocation, ubiquitination and deglycosylation. Interacts with DRL1. Interacts (through a region distinct from the RING finger) with UBE2G2/UBC7. Component of the VCP/p97-AMFR/gp78 complex that enhances VCP/p97 binding to polyubiquitinated proteins for their degradation by the endoplasmic reticulum-associated degradation (ERAD) pathway. Interacts (via the VIM) with VCP/p97. Interacts (via its membrane domain) with INSIG1; the interaction initiates the sterol-mediated ubiquitination and degradation of HMGCR by the ERAD pathway. 2 isoforms of the human protein are produced by alternative splicing.

Protein type: EC 6.3.2.-; EC 6.3.2.19; Endoplasmic reticulum; Ligase; Membrane protein, integral; Membrane protein, multi-pass; Motility/polarity/chemotaxis; Receptor, misc.; Ubiquitin conjugating system; Ubiquitin ligase

Chromosomal Location of Human Ortholog: 16q13

Cellular Component: endoplasmic reticulum membrane; integral to endoplasmic reticulum membrane; membrane; perinuclear region of cytoplasm; protein complex

Molecular Function: chaperone binding; protein binding; protein binding, bridging; receptor activity; ubiquitin-protein ligase activity

Biological Process: cell motility; ER-associated protein catabolic process; positive regulation of protein binding; protein autoubiquitination; protein oligomerization; protein polyubiquitination; protein ubiquitination during ubiquitin-dependent protein catabolic process; signal transduction; ubiquitin-dependent protein catabolic process; unfolded protein response