Assembly of the rotavirus outer capsid is the final step of a complex pathway. In vivo, the later steps include a maturational membrane penetration that is dependent on the scaffolding activity of a viral nonstructural protein. In vitro, simply adding the recombinant outer capsid proteins VP4 and VP7 to authentic double-layered rotavirus subviral particles (DLPs) in the presence of calcium and ...

Birnavirus-encoded viral protein 4 (VP4) utilizes a Ser/Lys catalytic dyad mechanism to process polyprotein. Here three phosphorylated amino acid residues Ser538, Tyr611 and Thr674 within the VP4 protein of the infectious bursal disease virus (IBDV), a member of the genus Avibirnavirus of the family Birnaviridae, were identified by mass spectrometry. Anti-VP4 monoclonal antibodies finely mappin...

Most strains of animal rotaviruses are able to agglutinate erythrocytes, and the surface protein VP4 is the virus hemagglutinin. To map the hemagglutination domain on VP4 while preserving the conformation of the protein, we constructed full-length chimeras between the VP4 genes of hemagglutinating (YM) and nonhemagglutinating (KU) rotavirus strains. The parental and chimeric genes were expresse...

Numerous prior studies have indicated that viable rotavirus reassortants containing structural proteins of heterologous parental origin may express unexpected phenotypes, such as changes in infectivity and immunogenicity. To provide a structural basis for alterations in phenotypic expression, a three-dimensional structural analysis of these reassortants was conducted. The structures of the reas...

cDNA clones representing the VP4 gene of symptomatic human rotavirus strain KU (VP7 serotype 1) or DS-1 (VP7 serotype 2) or asymptomatic human rotavirus strain 1076 (VP7 serotype 2) were constructed and inserted into a baculovirus expression vector under the control of the polyhedrin promoter. The resulting recombinants expressed the appropriate authentic VP4 rotavirus outer capsid protein. Gui...

The polyprotein of infectious bursal disease virus (IBDV), an avian birnavirus, is processed by the viral protease, VP4. Previous data obtained on the VP4 of infectious pancreatic necrosis virus (IPNV), a fish birnavirus, and comparative sequence analysis between IBDV and IPNV suggest that VP4 is an unusual eukaryotic serine protease that shares properties with prokaryotic leader peptidases and...

Coxsackievirus B4 (CVB4)-induced production of alpha interferon (IFN-alpha) by peripheral blood mononuclear cells (PBMC) is enhanced in vitro by nonneutralizing anti-CVB4 antibodies from healthy subjects and, to a higher extent, from patients with insulin-dependent diabetes mellitus. In this study, we focused on identification of the viral target of these antibodies in CVB systems. High levels ...

Nonenveloped viruses are generally released from the cell by the timely lysis of host cell membranes. SV40 has been used as a model virus for the study of the lytic nonenveloped virus life cycle. The expression of SV40 VP4 at later times during infection is concomitant with cell lysis. To investigate the role of VP4 in viral release and its mechanism of action, VP4 was expressed and purified fr...

Background: VP4 protein is as spikes on rotavirus outer capsid shell which is responsible for virus attachment to the host. VP4 induces production of neutralizing antibodies which could be used for serotyping of different isolates. Methods: Simian rotavirus SA11 gene 4 cDNA was cloned into a cloning plasmid pDONRTM by recombination reaction using clonase II enzyme mix. The resulting clone was c...