Spatial relationships of the proteins of vesicular stomatitis virus: induction of reversible oligomers by cleavable protein cross-linkers and oxidation.
To delineate the proximity and spatial arrangement of the major structural proteins of intact vesicular stomatitis (VS) virions, protein complexes formed by oxidation or by bivalent cross-linkers were analyzed by two-dimensional electrophoresis on polyacrylamide slab gels. H2O2 oxidation of VS virions produced an N-polypeptide dimer (molecular weight, approximately equal to 110,000) on a first dimension gel that could be reduced to N monomers (molecular weight, approximately equal to 50,000). Proteins extracted from unreduced and unoxidized VS virions contained dimeric and trimeric forms of M-protein complexes as well as a heterodimer of M and N protein. Qualitatively similar VS viral protein complexes were generated by exposing VS virions to the reversible protein cross-linkers methyl-4-mercaptobutyrimidate (MMB), tartryl diazide (TDA), and dithiobis(succinimidyl proprionate) (DTBSP); cross-linked complexes on first-dimension gels were cleaved by reduction with 2-mercaptoethanol (MMB or DTBSP cross-linked) or by periodate oxidation (TDA cross-linked). In addition to covalently linked homodiamers of M and N proteins and a protein M-N heterodimer, the protein cross-linkers also generated homo-oligomers of G protein and a G-M heterodimer. These data suggest that the glycoprotein spike of VS virus is composed of more than one G protein. The existence of N-M and G-M heterodimers is consistent with the hypothesis that the matrix (M) protein may serve as a bridge between the G and N proteins in assembly of the VS virion.
D002460:Cell Line; D006023:Glycoproteins / Q000032:analysis; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010455:Peptides / Q000032:analysis / Q000378:metabolism; D011487:Protein Conformation; D014721:Vesicular stomatitis Indiana virus / Q000378:metabolism / Q000648:ultrastructure*; D014764:Viral Proteins / Q000032:analysis* / Q000378:metabolism
D006023:Glycoproteins; D010455:Peptides; D014764:Viral Proteins