Disease relevance of VP2

• Location of the sequences coding for capsid proteins VP1 and VP2 on polyoma virus DNA [1].
• Comparison of the chain lengths of the capsid proteins with the size of the viral mRNAs coding for them suggests that VP1 and VP2 are entirely virus-coded [1].
• Coproduction of the capsid proteins VP1, VP2, and VP3 was achieved by infecting Sf9 cells with the three recombinant baculovirus species at equal multiplicities [2].
• We consider the implications of this unusual modification on encapsidation and suggest that VP2 may be a scaffolding protein for virion assembly [3].
• Here we show that VP2 from both polyoma virus and simian virus 40 (SV40) is covalently linked to myristic acid; this is the first report of a myristylated protein in the nucleus and of a fatty acid being important in the structure of a nonenveloped virus [3].

High impact information on VP2

• Overlapping of the VP2-VP3 gene and the VP1 gene in the SV40 genome [4].
• The 16S RNA codes only for polyoma capsid protein VP1, while the 19S RNA codes in addition for capsid protein VP2 [1].
• Since the 19S and 16S species have been previously mapped on the viral genome, these results allow us to deduce the location of the sequences coding for VP1 and VP2 [1].
• When VP1 was coexpressed with VP2, the nonphysiologic serine phosphorylation of VP1 was decreased, and a tryptic peptide containing Thr-63, a site modified during virus infection of mouse cells, was phosphorylated [5].
• A stretch of 49 amino acids of VP2 served as an anchor molecule, either expressed as a fusion protein with green fluorescent protein (GFP) or covalently linked to methotrexate (MTX) [6].

Chemical compound and disease context of VP2

• The polyomavirus minor late capsid antigen, VP2, is myristylated on its N-terminal glycine, this modification being required for efficient infection of mouse cells [7].
• The VP2-size in vitro product contained all the virion VP2 methionine-labeled tryptic peptides, as shown by cation- and anion-exchange chromatography and two-dimensional fingerprinting on cellulose [8].
• To study the function of this modification and the role of VP2 in the life cycle of polyomavirus, the N-terminal glycine, critical to the myristylation consensus sequence, has been altered to a glutamic acid or a valine residue by site-directed oligonucleotide mutagenesis [9].
• However, a large amount of (3H) tryptophan was found in the viral polypeptide VP3 relative to that incorporated into the capsid polypeptides VP1 and VP2 [10].
• Polyoma capsid proteins VP1 and VP2 have been identified in the cell-free product by polyacrylamide gel electrophoresis, specific immunoprecipitation, and tryptic peptide fingerprinting [11].

Biological context of VP2

• The sequence information needed for assigning genotypes can be captured by VP1, VP2, VP3, or large T-gene sequencing [12].
• Three putative capsid proteins VP1, VP2, and VP3 are encoded by alternative open reading frames [13].
• The change in phosphorylation resulting from coexpression of two structural proteins identifies the potential of the baculovirus system for studying protein-protein interactions and defines a functional role for the VP1-VP2 interaction [5].
• Polyoma virus DNA: complete nucleotide sequence of the gene which codes for polyoma virus capsid protein VP1 and overlaps the VP2/VP3 genes [14].
• Myristylated polyomavirus VP2: role in the life cycle of the virus [9].

Anatomical context of VP2

• VP2 and VP3, but not VP1, caused the permeabilization of bacterial membranes [15].
• That a glycine at VP2 221 will inhibit virus replication in chicken embryo fibroblasts (CEFs) has been previously reported [16].
• Simian virus 40 capsid proteins VP-1, VP-2, and VP-3 have been synthesized in wheat germ and reticulocyte cell-free systems in response to either poly(A)-containing mRNA from the cytoplasm of infected cells or viral RNA purified by hybridization to simian virus 40 DNA linked to Sepharose [17].

Associations of VP2 with chemical compounds

• Other experiments showed that the VP2 and VP3 can be labeled with formyl methionine from initiator tRNA [18].
• The N-terminal glycine of the VP2 coat protein has been shown to be cotranslationally acylated with myristic acid [9].
• VP1, VP2, and vp3 were all labeled with [35S] formylmethionine when they were synthesized in the presence of [35S] formylmethionyl-tRNAfmet [19].
• Polyoma mRNA species have been isolated by preparative hybridization to purified viral DNA immobilized on cellulose nitrate filters and shown to code for both VP1 and VP2 [11].
• In contrast, six of seven of the new APVs isolated in CEFs had a glycine at VP2 221 [16].

Physical interactions of VP2

• Recombinant VP1 coimmunoprecipitated with recombinant VP2 or truncated VP2 (delta C12VP2), which lacked the carboxy-terminal 12 amino acids [20].

Other interactions of VP2

• The NCCRs of the several Indian endemic strains were analysed by sequencing PCR products, amplified directly from urine samples, with oligonucleotide primers designed from the constant region of T-Antigen and VP2 coding sequences [21].

Analytical, diagnostic and therapeutic context of VP2

• Immunoprecipitation of lysates from co-infected cells demonstrated an association between VP1 and VP2 [22].
• As determined by immunogold electron microscopy, when expressed alone VP2 was associated with membrane structures in the cytoplasm and VP3 was diffusely localized in the cytoplasm [22].
• This protein-protein interaction was substantiated by laser scanning confocal microscopy of Sf9 cells that were co-infected with VP1, VP2 and VP3 recombinant viruses [23].
• Polyclonal serum to this protein which reacted specifically with recombinant VP2 as well as polyomavirus virion VP2 and VP3 on Western blots (immunoblots) was produced [20].
• The three cytoplasmic polyadenylated mRNA's which separately encode the three capsid proteins (VP1, VP2, and VP3) of polyoma virus were mapped on the viral genome by one- and two-dimensional gel electrophoreses of nuclease S1-resistant RNA-DNA hybrids [24].

References