title: The isoelectric point of the p30 polypeptide as a marker of mouse endogenous viruses.
abstract: The isoelectric point (PI) of the p30 polypeptide of members of the three known classes of mouse C-type endogenous viruses was determined both by column and by thin-layer gel isoelectric focusing. Each class was found to be characterized by a particular variant of p30 (isop30), with pI values of 6.1 for class I (ecotropic), 5.7 for class II (xenotropic), and 5.5 for class III (NZB, NIH, ATS124, also xenotropic). The 6.1-isop30 was found as a minor component of rat-grown NZB virus and of a number of laboratory strains of mouse C-type viruses.
mesh_terms: D000818:Animals; D017988:Gammaretrovirus / Q000032:analysis*; D007526:Isoelectric Point; D051379:Mice; D008815:Mice, Inbred Strains; D010455:Peptides / Q000032:analysis*; D012190:Retroviridae / Q000032:analysis*; D014764:Viral Proteins / Q000032:analysis*
chemical_list: D010455:Peptides; D014764:Viral Proteins