Structural analysis of the spleen focus-forming virus envelope gene product.
The structure of the envelope gene product (gp52) of the spleen focus-forming virus was analyzed and compared to that of envelope proteins (gp70 and p15E) of another pathogenic Friend virus recombinant, Friend mink cell focus-inducing virus (F-MCF). This has enabled us to confirm and extend previous nucleotide sequence data regarding the make up of specific domains of the SFFV glycoprotein. Amino-terminal 23,000-Da V8 protease fragments from gp52 of the Lilly-Steeves strain of SFFV and from gp70 of a pathogenic F-MCF isolate produced tryptic peptide fingerprints in which the mobilities of the trypsin-generated peptides were identical. The carboxyl-terminal, 21,000 Da, V8 protease fragment of gp52, however, has a unique fingerprint that contained a single highly charged trypsin-generated peptide. This peptide migrated to the same position as a peptide in F-MCF p15E, thus indicating that the p15E-related nucleotide sequences, that follow the large envelope deletion, are translated in the same reading frame as those in the standard p15E. Although R peptide determinants can be detected in F-MCF Pr15E, they could not be detected in gp52. The amino-terminal 23K domain of gp52, like that of MCF gp70, contains two oligosaccharide attachment sites. The other two attachment sites are located within the 21K carboxyl-terminal domain.
D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D005622:Friend murine leukemia virus / Q000235:genetics*; D005796:Genes; D005814:Genes, Viral; D006027:Glycosides / Q000032:analysis; D007668:Kidney; D051379:Mice; D008970:Molecular Weight; D010446:Peptide Fragments / Q000032:analysis; D051381:Rats; D011916:Rats, Inbred F344; D014759:Viral Envelope Proteins / Q000235:genetics* / Q000302:isolation & purification
D006027:Glycosides; D010446:Peptide Fragments; D014759:Viral Envelope Proteins