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 | ||||||||
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References
edit- ^ Kelleher DJ, Gilmore R (2006). "An evolving view of the eukaryotic oligosaccharyltransferase". Glycobiology. 16 (4): 47R–62R. doi:10.1093/glycob/cwj066. PMID 16317064.
- ^ Gayen S, Kang C (2011). "Solution structure of a human minimembrane protein Ost4, a subunit of the oligosaccharyltransferase complex". Biochem Biophys Res Commun. 409 (3): 572–6. doi:10.1016/j.bbrc.2011.05.050. PMID 21609714.
- ^ Spirig U, Bodmer D, Wacker M, Burda P, Aebi M (2005). "The 3.4-kDa Ost4 protein is required for the assembly of two distinct oligosaccharyltransferase complexes in yeast". Glycobiology. 15 (12): 1396–406. doi:10.1093/glycob/cwj025. hdl:20.500.11850/30954. PMID 16096346.
Chi, J.H., Roos, J. and N. Dean. (1996) The OST4 gene of Saccharomyces cerevisiae encodes an unusually small protein required for normal levels of oligosaccharyltransferase activity J. Biol. Chem. 271;3132-3140.