Functional Analysis of Endoplasmic Reticulum Glucosyltransferase (UGGT) Using Synthetic Glycans

Abstract

UGGT1 is called a folding sensor protein that recognizes misfolded glycoproteins and selectively glucosylates high-mannose-type glycans on the proteins. However, the use of conventional naturally occurring glycoproteins is insufficient for performing quantitative analysis of the unique properties of UGGT1. We have demonstrated that high-mannose-type glycans, in which various hydrophobic aglycons were introduced, act as good substrates for UGGT1 and are useful analytical tools for its characterization. Moreover, we found that UGGT2, an isoform UGGT1, is also capable of glucosylating these synthetic substrates.