Oligosaccaryltransferase

See also: Dolichyl-diphosphooligosaccharide–protein glycotransferase

In molecular biology, OST4 (Dolichyl-diphosphooligosaccharide—protein glycosyltransferase subunit 4) is a subunit of the oligosaccharyltransferase complex.^[1] OST4 is a very short, approximately 30 amino acids, protein found from fungi to vertebrates. It appears to be an integral membrane protein that mediates the en bloc transfer of a pre-assembled high-mannose oligosaccharide onto asparagine residues of nascent polypeptides as they enter the lumen of the rough endoplasmic reticulum.^[2][3]

Oligosaccaryltransferase
nmr structure of yeast oligosaccharyltransferase subunit ost4p
Identifiers
Symbol	Ost4
Pfam	PF10215
InterPro	IPR018943
OPM superfamily	242
OPM protein	2lat
Membranome	465
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary