Glycosylation of hepatitis C virus envelope proteins.

Enveloped viruses are surrounded by a membrane derived from the host-cell that contains proteins called "envelope proteins". These proteins play a major role in virus assembly and entry. In most of the enveloped viruses, they are modified by N-linked glycosylation which is supposed to play a role in their stability, antigenicity and biological functions. Glycosylation is also known to play a major role in the biogenesis of proteins by being directly and/or indirectly involved in protein folding. Recent studies on hepatitis C virus (HCV) envelope proteins have revealed a complex interplay between cleavage by signal peptidase, folding and glycosylation. The knowledge that has been accumulated on the early steps of glycosylation of these proteins is presented in this review.