Efficient infection of cells by human papillomaviruses (HPVs) and pseudovirions requires primary interaction with cell surface proteoglycans with apparent preference for species carrying heparan sulfate (HS) side chains. To identify residues contributing to virus/cell interaction, we performed point mutational analysis of the HPV16 major capsid protein, L1, targeting surface-exposed amino acid residues. Replacement of lysine residues 278, 356, or 361 for alanine reduced cell binding and infectivity of pseudovirions.
View Article and Find Full Text PDFBackground: Infections with papillomaviruses induce type-specific immune responses, mainly directed against the major capsid protein, L1. Based on the propensity of the L1 protein to self-assemble into virus-like particles (VLPs), type-specific vaccines have already been developed. In order to generate vaccines that target a broader spectrum of HPV types, extended knowledge of neutralizing epitopes is required.
View Article and Find Full Text PDFPapillomaviruses enter cells via endocytosis (H. C. Selinka et al.
View Article and Find Full Text PDFMinor capsid protein L2 of papillomaviruses plays an essential role in virus assembly by recruiting viral components to PML bodies, the proposed sites of virus morphogenesis. We demonstrate here that the function of L2 in virus assembly requires the chaperone Hsc70. Hsc70 was found dispersed in naturally infected keratinocytes and cultured cells.
View Article and Find Full Text PDFIn this report, the tropism of papillomaviruses, the structure of virions, the function of viral proteins and the use of pseudovirions for the analysis of the immune response against papillomaviruses and the search for the viral receptor are briefly described.
View Article and Find Full Text PDFThe major and minor capsid proteins of polyomavirus are preassembled in the cytoplasm and translocated to the nucleus only as a VP1-VP2/VP3 complex. In this study, we describe independent nuclear translocation of the L1 major protein and the L2 minor capsid protein of human papillomavirus type 33 by several approaches. First, we observed that expression and nuclear translocation of L2 in natural lesions precede expression of L1.
View Article and Find Full Text PDFNuclear domains (ND) 10 are associated with proteins implicated in transcriptional regulation, growth suppression, and apoptosis. We now show that the minor capsid protein L2 of human papillomavirus (HPV) type 33 induces a reorganization of ND10-associated proteins. Whereas the promyelocytic leukemia protein, the major structural component of ND10, was unaffected by L2, Sp100 was released from ND10 upon L2 expression.
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