CALNEXIN, CALRETICULIN AND THE FOLDING OF GLYCOPROTEINS

Calnexin and calreticulin are molecular chaperones in the endoplasmic reticulum (ER). They are lectins that interact with newly synthesized glycoproteins that have undergone partial trimming of their core N-lin ked oligosaccharides. Together with the enzymes responsible for glucos e removal and a glucosyltransferase that re-glucosylates already-trimm ed glycoproteins, they provide a novel mechanism for promoting folding , oligomeric assembly and quality control in the ER.