The unexpected structures of hepatitis C virus envelope proteins

Hepatitis C virus (HCV) envelope proteins are essential not only for maintaining the viral life cycle, but also for evading the host's immune response and in clinical intervention. A thorough understanding of HCV envelope proteins depends on the availability of detailed structural information. Two crystal structures of the E2 core portion and of the E2 ectodomain, and one structure of the N-terminus of E1 ectodomain have shed new light on the complexity of HCV envelope proteins. In addition, the full-length E1-E2 complex has recently been modeled. The present review focuses on these advancements, introduces the recently solved structures and their biological implications and proposes novel ideas for studying the full-length E1-E2 complex.