Abstract
Growing evidence indicates that the processing of asparagine-linked oligosaccharides is coupled with the quality control of glycoproteins in cells. Namely, the intracellular lectins operating as molecular chaperones, cargo receptors, and ubiquitin ligases recognize partially trimmed intermediates of high-mannose-type glycans and thereby govern the intracellular processes of folding, transport, and degradation of carrier polypeptides. These intracellular lectins have unique mechanisms to check folding states of glycoproteins and to sense the subcellular environmental conditions. This review provides an overview on our current knowledge of the structural and molecular basis for glycoprotein-fate determination in cells through sugar recognition by the lectins.
