%0 Journal Article %A Yamamoto, Mami %A Aizaki, Hideki %A Fukasawa, Masayoshi %A Teraoka, Tohru %A Miyamura, Tatsuo %A Wakita, Takaji %A Suzuki, Tetsuro %T Structural requirements of virion-associated cholesterol for infectivity, buoyant density and apolipoprotein association of hepatitis C virus %D 2011 %J Journal of General Virology, %V 92 %N 9 %P 2082-2087 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.032391-0 %I Microbiology Society, %X Our earlier study has demonstrated that hepatitis C virus (HCV)-associated cholesterol plays a key role in virus infectivity. In this study, the structural requirement of sterols for infectivity, buoyant density and apolipoprotein association of HCV was investigated further. We removed cholesterol from virions with methyl β-cyclodextrin, followed by replenishment with 10 exogenous cholesterol analogues. Among the sterols tested, dihydrocholesterol and coprostanol maintained the buoyant density of HCV and its infectivity, and 7-dehydrocholesterol restored the physical appearance of HCV, but suppressed its infectivity. Other sterol variants with a 3β-hydroxyl group or with an aliphatic side chain did not restore density or infectivity. We also provide evidence that virion-associated cholesterol contributes to the interaction between HCV particles and apolipoprotein E. The molecular basis for the effects of different sterols on HCV infectivity is discussed. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.032391-0