Adenovirus Type 12 Gene 401 Function and Temperature Sensitivity of Cytochalasin B Effects on Transformed Cells

Rat (3Y1) cells transformed by wild-type adenovirus type 12 or the temperature-sensitive mutant ts401 with an active function required for transformation maintenance were exposed at the permissive(36 degrees) or nonpermissive (40 degrees) temperature to cytochalasin B (CB). At 40 degrees, the ts401-transformed cells, but not the wild-type transformants, exhibited, at least partially, the untransformed 3Y1 cell phenotype; most of the cells became bi- and trinucleated and DNA synthesis was inhibited. AT 36 degrees, both groups of cells became highly multinucleated, and there was no apparent inhibition of DNA synthesis by CB. These characteristics were exhibited also by the wild-type transformants at 40 degrees. These findings provide additional evidence that an active 401 gene function is required for maintenance of the adenovirus-transformed cell phenotype.