Viruses 2014, 6, 1149-1187; doi:10.3390/v6031149 OPEN ACCESS viruses ISSN 1999-4915 www.mdpi.com/journal/viruses Review Incorporation of Hepatitis C Virus E1 and E2 Glycoproteins: The Keystones on a Peculiar Virion Gabrielle Vieyres 1,*, Jean Dubuisson 2,3,4,5 and Thomas Pietschmann 1 1 Institute of Experimental Virology, Twincore, Center for Experimental and Clinical Infection Research, a Joint Venture between the Medical School Hannover and the Helmholtz Center for Infection Research, 30625 Hannover, Germany; E-Mail:
[email protected] 2 Institut Pasteur de Lille, Center for Infection & Immunity of Lille (CIIL), F-59019 Lille, France; E-Mail:
[email protected] 3 CNRS UMR8204, F-59021 Lille, France 4 Inserm U1019, F-59019 Lille, France 5 Université Lille Nord de France, F-59000 Lille, France * Author to whom correspondence should be addressed; E-Mail:
[email protected]; Tel.: +49-511-22-00-27-134; Fax: +49-511-22-00-27-139. Received: 18 December 2013; in revised form: 21 February 2014 / Accepted: 27 February 2014 / Published: 11 March 2014 Abstract: Hepatitis C virus (HCV) encodes two envelope glycoproteins, E1 and E2. Their structure and mode of fusion remain unknown, and so does the virion architecture. The organization of the HCV envelope shell in particular is subject to discussion as it incorporates or associates with host-derived lipoproteins, to an extent that the biophysical properties of the virion resemble more very-low-density lipoproteins than of any virus known so far. The recent development of novel cell culture systems for HCV has provided new insights on the assembly of this atypical viral particle.