THE FUNCTIONAL E1–E2 HETERODIMER HCV GLYCOPROTEINS

,

Abstract

Introduction: The two HCV envelope glycoproteins E1 and E2 are released from
HCV polyprotein by signal peptidase cleavages. These glycoproteins are type I transmembrane
proteins with a highly glycosylated N-terminal ectodomain and a C-terminal hydrophobic
anchor. Methods and pathways: After their synthesis, HCV glycoproteins E1 and E2 associate
as a non covalent heterodimer. The transmembrane domains of HCV envelope glycoproteins
play a major role in E1–E2 heterodimer assembly and subcellular localization. The envelope
glycoprotein complex E1–E2 has been proposed to be essential for HCV entry. Results and
conclusions: However, for a long time, HCV entry studies have been limited by the lack of a
robust cell culture system for HCV replication and viral particle production. Recently, a model
mimicking the entry process of HCV lifecycle has been developed by pseudo typing retroviral
particles with native HCV envelope glycoproteins, allowing the characterization of functional
E1–E2 envelope glycoproteins., we review our understanding to date on the assembly of the
functional HCV glycoprotein heterodimer.