The core (C) protein of hepatitis C virus (HCV) appears to be a multifunctional protein that is involved in many viral and cellular processes. Although its effects on host cells have been extensively discussed in the literature, little is known about its main function, the assembly and packaging of the viral genome. We have studied the in vitro assembly of several deleted versions of recombinant HCV C protein expressed in E. coli. We demonstrated that the 75 N-terminal residues of the C protein were sufficient to assemble and generate nucleocapsid-like particles (NLPs) in vitro. However, homogeneous particles of regular size and shape were observed only when NLPs were produced from at least the first 79 N-terminal amino acids of the C protein. This small protein unit fused to the endoplasmic reticulum-anchoring domain also generated NLPs in yeast cells. These data suggest that the N-terminal half of the C protein is important for formation of NLPs. Similarities between the HCV C protein and C proteins of other members of the Flaviviridae are discussed.
AcharyaN.,
VarshneyU.2002; Biochemical properties of single-stranded DNA-binding protein from Mycobacterium smegmatis , a fast-growing mycobacterium and its physical and functional interaction with uracil DNA glycosylases. J Mol Biol 318:1251–1264
Acosta-RiveroN.,
MusacchioA.,
LorenzoL.,
AlvarezC.,
MoralesJ.2002; Processing of the hepatitis C virus precursor protein expressed in the methylotrophic yeast Pichia pastoris
. Biochem Biophys Res Commun 295:81–84
AndreP.,
Komurian-PradelF.,
DeforgesS.7 other authors2002; Characterization of low- and very-low-density hepatitis C virus RNA-containing particles. J Virol 76:6919–6928
ChooQ.,
KuoG.,
RalstonR.15 other authors1994; Vaccination of chimpanzees against infection by the hepatitis C virus. Proc Natl Acad Sci U S A 91:1294–1298
DeresK.,
SchroderC. H.,
PaessensA.17 other authors2003; Inhibition of hepatitis B virus replication by drug-induced depletion of nucleocapsids. Science 299:893–896
FalconV.,
GarciaC.,
RosaM. C. d. I.,
MenendezI.,
SeoaneJ.,
GrilloJ. M.1999; Ultrastructural and immunocytochemical evidences of core-particle formation in the methylotrophic Pichia pastoris yeast when expressing HCV structural proteins (core-E1). Tissue Cell 31:117–125
FalconV.,
Acosta-RiveroN.,
ChineaG.7 other authors2003; Ultrastructural evidences of HCV infection in hepatocytes of chronically HCV-infected patients. Biochem Biophys Res Commun 305:1085–1090
GrakouiA.,
WychowskiC.,
LinC.,
FeinstoneS. M.,
RiceC.1993; Expression and identification of hepatitis C virus polyprotein cleavage products. J Virol 67:1385–1395
HopeR. G.,
McLauchlanJ.2000; Sequence motifs required for lipid droplet association and protein stability are unique to the hepatitis C virus core protein. J Gen Virol 81:1913–1925
HopeR. G.,
MurphyD. J.,
McLauchlanJ.2002; The domains required to direct core proteins of hepatitis C virus and GB virus-B to lipid droplets share common features with plant oleosin proteins. J Biol Chem 277:4261–4270
HüssyP.,
LangenH.,
MousJ.,
JacobsenH.1996; Hepatitis C virus core protein: carboxy-terminal boundaries of two processed species suggest cleavage by a signal peptide peptidase. Virology 224:93–104
IlariA.,
JohnsonK. A.,
NastopoulosV.,
VerziliD.,
ZamparelliC.,
ColottiG.,
TsernoglouD.,
ChianconeE.2002; The crystal structure of the sorcin calcium binding protein domain provides a model of Ca2+-dependent processes in the full-length protein. J Mol Biol 317:447–458
LiD.,
TakyarS. T.,
LottW. B.,
GowansE. J.2003; Amino acids 1–20 of the hepatitis C virus (HCV) core protein specifically inhibit HCV IRES-dependent translation in HepG2 cells, and inhibit both HCV IRES- and cap-dependent translation in HuH7 and CV-1 cells. J Gen Virol 84:815–825
LinC.,
LindenbachB. D.,
PragalB. M.,
McCourtD. W.,
RiceC. M.1994; Processing in the hepatitis C virus E2–NS2 region: identification of p7 and two distinct E2-specific products with different C termini. J Virol 68:5063–5073
LiuQ.,
TackneyC.,
BhatR.,
PrinceA.,
ZhangP.1997; Regulated processing of hepatitis C virus core protein is linked to subcellular localization. J Virol 71:657–662
LorenzoL. J.,
Duenas-CarreraS.,
FalconV.,
Acosta-RiveroN.,
GonzalezE.,
de la RosaM. C.,
MenendezI.,
MoralesJ.2001; Assembly of truncated HCV core antigen into virus-like particles in Escherichia coli
. Biochem Biophys Res Commun 281:962–965
LyonsA. J.,
RobertsonH. D.2003; Detection of tRNA-like structure through RNase P cleavage of viral internal ribosome entry site RNAs near the AUG start triplet. J Biol Chem 278:26844–26850
MaH.-C.,
KeC.-H.,
HsiehT.-Y.,
LoS.-Y.2002; The first hydrophobic domain of the hepatitis C virus E1 protein is important for interaction with the capsid protein. J Gen Virol 83:3085–3092
MaillardP.,
KrawczynskiK.,
NitkiewiczJ.7 other authors2001; Nonenveloped nucleocapsids of hepatitis C virus in the serum of infected patients. J Virol 75:8240–8250
MandlC. W.,
HeinzF. X.,
KunzC.1988; Sequence of the structural proteins of tick-borne encephalitis virus (western subtype) and comparative analysis with other flaviviruses. Virology 166:197–205
McLauchlanJ.,
LembergM. K.,
HopeG.,
MartoglioB.2002; Intramembrane proteolysis promotes trafficking of hepatitis C virus core protein to lipid droplets. EMBO J 21:3980–3988
NolandtO.,
KernV.,
MüllerH.,
PfaffE.,
TheilmannL.,
WelkerR.,
KräusslichH.-G.1997; Analysis of hepatitis C virus core protein interaction domains. J Gen Virol 79:1331–1340
ShimizuY.,
FeinstoneS.,
KoharaM.,
PurcellR.,
YoshikuraH.1996; Hepatitis C virus: detection of intracellular virus particles by electron microscopy. Hepatology 23:205–209
ToyodaH.,
KumadaT.,
TokudaA.13 other authors2000; Long-term follow-up of sustained responders to interferon therapy, in patients with chronic hepatitis C. J Viral Hepat 6:414–419
XiangJ.,
KlinzmanD.,
McLindenJ.,
SchmidtW. N.,
LaBrecqueD. R.,
GishR.,
StapletonJ. T.1998; Characterization of hepatitis G virus (GB-C virus) particles: evidence for a nucleocapsid and expression of sequences upstream of the E1 protein. J Virol 72:2738–2744
YasuiK.,
WakitaT.,
Tsukiyama-KoharaK.,
FunahashiS.-I.,
IchikawaM.,
KajitaT.,
MoradpourD.,
WandsJ. R.,
KoharaM.1998; The native form and maturation process of hepatitis C virus core protein. J Virol 72:6048–6055