EMC4

EMC4 (ER Membrane Protein Complex Subunit 4) functions in apoptotic process, protein folding in endoplasmic reticulum

Full Name

ER Membrane Protein Complex Subunit 4

Research Area

Part of the endoplasmic reticulum membrane protein complex (EMC) that enables the energy-independent insertion into endoplasmic reticulum membranes of newly synthesized membrane proteins (PubMed:30415835, PubMed:29809151, PubMed:29242231, PubMed:32459176, PubMed:32439656).

Preferentially accommodates proteins with transmembrane domains that are weakly hydrophobic or contain destabilizing features such as charged and aromatic residues (PubMed:30415835, PubMed:29809151, PubMed:29242231).

Involved in the cotranslational insertion of multi-pass membrane proteins in which stop-transfer membrane-anchor sequences become ER membrane spanning helices (PubMed:30415835, PubMed:29809151).

It is also required for the post-translational insertion of tail-anchored/TA proteins in endoplasmic reticulum membranes (PubMed:29809151, PubMed:29242231).

By mediating the proper cotranslational insertion of N-terminal transmembrane domains in an N-exo topology, with translocated N-terminus in the lumen of the ER, controls the topology of multi-pass membrane proteins like the G protein-coupled receptors (PubMed:30415835).

By regulating the insertion of various proteins in membranes, it is indirectly involved in many cellular processes (Probable).

Biological Process

Apoptotic process Source: UniProtKB-KW
Protein insertion into ER membrane by stop-transfer membrane-anchor sequence Source: UniProtKB
Tail-anchored membrane protein insertion into ER membrane Source: UniProtKB

Cellular Location

Endoplasmic reticulum membrane. Could also be a single-pass transmembrane protein with cytosolic N-terminus and lumenal C-terminus.

Topology

Cytoplasmic: 2-66
Helical: 67-87
Lumenal: 88-98
Helical: 99-120
Cytoplasmic: 121-127
Helical: 128-148
Lumenal: 149-183