The Endoplasmic Reticulum Chaperone Cosmc Directly Promotes in Vitro Folding of T-synthase

The T-synthase is the key β3-galactosyltransferase essential for biosynthesis of core 1 O-glycans (Galβ1–3GalNAcα1-Ser/Thr) in animal cell glycoproteins. Here we describe the novel ability of an endoplasmic reticulum-localized molecular chaperone termed Cosmc to specifically interact with partly den...

Full description

Saved in:
Bibliographic Details
Published in:The Journal of biological chemistry 2010-01, Vol.285 (4), p.2456-2462
Main Authors: Aryal, Rajindra P., Ju, Tongzhong, Cummings, Richard D.
Format: Article
Language:English
Subjects:
Adenosine Triphosphate - metabolism
Biomarkers, Tumor - metabolism
Chaperones/Protein Folding
Cosmc
Endoplasmic Reticulum
Endoplasmic Reticulum - enzymology
Galactosyltransferase
Galactosyltransferases - chemistry
Galactosyltransferases - metabolism
Gene Expression - physiology
Glycobiology and Extracellular Matrices
Hot Temperature
Humans
In Vitro Techniques
Luciferases - genetics
Molecular Chaperone
Molecular Chaperones - chemistry
Molecular Chaperones - genetics
Molecular Chaperones - metabolism
N-Acetylgalactosaminyltransferases
Oligopeptides - metabolism
Protein Denaturation
Protein Folding
Solubility
T-synthase
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The T-synthase is the key β3-galactosyltransferase essential for biosynthesis of core 1 O-glycans (Galβ1–3GalNAcα1-Ser/Thr) in animal cell glycoproteins. Here we describe the novel ability of an endoplasmic reticulum-localized molecular chaperone termed Cosmc to specifically interact with partly denatured T-synthase in vitro to cause partial restoration of activity. By contrast, a mutated form of Cosmc observed in patients with Tn syndrome has reduced chaperone function. The chaperone activity of Cosmc is specific, does not require ATP in vitro, and is effective toward T-synthase but not another β-galactosyltransferase. Cosmc represents the first ER chaperone identified to be required for folding of a glycosyltransferase.
ISSN:0021-9258
1083-351X
DOI:10.1074/jbc.M109.065169