Papovavirus structural polypeptides: comparison of human and rabbit papilloma viruses with simian virus 40

A comparative study of the structural polypeptides of purified human papilloma virus, rabbit papilloma virus, and simian virus 40 (SV40) was performed by electrophoretic analysis on 10% polyacrylamide gels containing sodium dodecyl sulfate either by Coomassie blue staining or by electrophoresing purified virus preparations labeled with radioactive iodine. Analysis of human papilloma virus on stained gels revealed 6 bands with a major polypeptide of molecular weight 63,000 daltons comprising 60% of the virion protein. Analysis of rabbit papilloma virus on stained gels revealed 5 bands with a major polypeptide of molecular weight 60,000 daltons comprising 48% of the virion protein. Under conditions which yielded 6 polypeptides for SV40, in agreement with published data, 4 and 7 polypeptides were regularly detected in iodinated preparations of human and rabbit papilloma viruses, respectively. Isoelectrofocusing of iodinated virions revealed isoelectric points of pH 3.7 for SV40 and pH 4.0 for both rabbit and human papilloma viruses.