COMPLEMENTATION AND TRANSFORMATION BY TEMPERATURE-SENSITIVE MUTANTS OF POLYOMA VIRUS

Temperature-sensitive mutants of polyoma virus have been studied in an attempt to understand the genetic structure of the virus, and to identify the viral functions required to promote malignant transformation. Six temperature-sensitive mutants of polyoma fall into three classes on the basis of complementation and transformation at the nonpermissive temperature. Two mutants (class I) are able to synthesize infectious viral DNA, but not mature virus particles. These two mutants transform normally at the nonpermissive temperature. Three mutants (class II) are defective in the synthesis of infectious viral DNA and are also defective in transformation. One mutant (class III) is defective in the synthesis of infectious viral DNA, but transforms normally. © 1969.