[Expression of ts-3 mutant of polyoma virus in mouse cells (author's transl)]

A thermosensitive mutant (ts-3) of polyoma virus produces T antigen, viral DNA and V antigen in BalbC/3T3 cells only at the permissive temperature (31 degrees C). At the non-permissive temperature (39 degrees C) these cells are unable to complement the viral defect. The pulse technique reveals only transitory cellular DNA induction between 15 and 25 h after infection at 39 degrees C. However, at both temperatures, cytoplasmic penetration is observed, and the viral DNA reaches the nuclei. Similarly, the myoblast cell line PCD2 does not complement the viral defect. In other idfferent types of cells tested (3T6, mouse kidney or secondary embryo cultures), the ts-3 mutant is expressed equally at 31 degrees C and 39 degrees C.