Transformation-specific antigen induced by oncogenic human adenovirus

Abstract

A TEMPERATURE-SENSITIVE (ts) mutant of the highly oncogenic group A (ref. 1) human adenovirus type 12 (H12), H12ts401 (ref. 2) is unable to establish stable transformation of cells in restrictive conditions³. Cells transformed by ts401 at the permissive temperature and shifted to nonpermissive temperatures show a reversion to a normal phenotype; wild-type H12-transformed cells, in contrast, exhibit a transformed phenotype when grown in either restrictive or permissive conditions⁴. The temperature sensitivity of the transformed phenotype of the ts401 mutant-transformed cells suggests that the continued expression of gene 401 is required for maintenance of the transformed cell phenotype. This study was initiated to detect the H12 transformation-specific protein(s) in H12-transformed cell lines. We identify here a 60,000 molecular weight transformation-specific antigen in H12-transformed rat 3Y1 cells^5,6 by immunoprecipitation of ³⁵S-methionine labelled polypeptides with serum from H12 tumour-bearing hamsters. Furthermore, the expression of this antigen is temperature dependent in 3Y1 cells transformed by ts401. Further characterisation of the 60,000 MW antigen may lead to an understanding of the molecular mechanism of adenovirus cell transformation.