title: Hepatitis C virus core protein is efficiently released into the culture medium in insect cells.
abstract: Hepatitis C virus (HCV) is a causal agent of the chronic liver infection. To understand HCV morphogenesis, we studied the assembly of HCV structural proteins in insect cells. We constructed recombinant baculovirus expression vectors consisting of either HCV core alone, core-E1, or core-E1-E2. These structural proteins were expressed in insect cells and were examined to assemble into particles. Neither core-E1 nor core-E1-E2 was capable of assembling into virus-like particles (VLPs). It was surprising that the core protein alone was assembled into core-like particles. These particles were released into the culture medium as early as 2 days after infection. In our system, HCV structural proteins including envelope proteins did not assemble into VLPs. Instead, the core protein itself has the intrinsic capacity to assemble into amorphous core-like particles. Furthermore, released core particles were associated with HCV RNA, indicating that core proteins were assembled into nucleocapsids. These results suggest that HCV may utilize a unique core release mechanism to evade the hosts defense mechanism, thus contributing to the persistence of HCV infection.
authors.affiliation: Ilsong Institute of Life Science, Hallym University, Chuncheon 200-702, Korea.
authors.forename: Soo Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: So Yeon
authors.initials: SY
authors.lastname: Kim
authors.forename: Kyu Jin
authors.initials: KJ
authors.lastname: Park
authors.forename: Yeon Joo
authors.initials: YJ
authors.lastname: Kim
authors.forename: Soon Bong
authors.initials: SB
authors.lastname: Hwang
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D003470:Culture Media / Q000737:chemistry*; D016174:Hepacivirus / Q000378:metabolism* / Q000472:pathogenicity; D006801:Humans; D007313:Insecta; D014758:Viral Core Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
chemical_list: D003470:Culture Media; D014758:Viral Core Proteins; C069130:nucleocapsid protein, Hepatitis C virus