Analysis of minimal sequences on JC virus VP1 required for capsid assembly

Abstract

Human JC virus (JCV) belongs to the family of Polyomaviridae. The viral capsid is composed of 72 capsomeres. Five VP1 molecules make up a capsomere structure. To investigate the minimal sequences on JCV VP1 polypeptide required for capsid assembly, the first 12 ( &#106 N12) and 19 ( &#106 N19) amino acids at the Nterminus and the last 16 ( &#106 C16), 17 ( &#106 C17), and 31 ( &#106 C31) amino acids at the C-terminus of VP1 were truncated and expressed in E. coli . The VP1 proteins of &#106 N12 and &#106 C16 were able to self-assemble into a virus-like particle similar to that of wild-type (WT) VP1. However, the mutant proteins of &#106 N19, &#106 C17, and &#106 C31 formed a pentameric capsomere structure as demonstrated by a 10-50% sucrose gradient centrifugation and electron microscopy. These results suggest that the 12 amino-terminal and 16 carboxy-terminal amino acids of VP1 are dispensable for the formation of virus-like particles, and further truncation at either end of VP1 leads to the loss of this property. Journal of NeuroVirology (2001) 7, 298-301.

• Jc Virus Vp1 Polypeptide Capsid Assembly