The T/t common region of simian virus 40 large T antigen contains a distinct transformation-governing sequence.
Simian virus 40 large T antigen (T) can transform cultured cells, but the mechanisms by which it functions are not entirely understood. Several lines of evidence have suggested that the amino-terminal approximately 130 residues of T may be sufficient to confer the transforming capability. Oligonucleotide-directed mutagenesis was used to generate a series of deletion and substitution mutants within the amino-terminal 82 residues of T, the segment which is shared with simian virus 40 small t antigen (t). Results of stability and transformation assays of these mutants strongly suggest that the 1-to-82 region of T contains sequences which govern T transforming activity and affect in vivo stability. Instability and a defect in transforming activity could be separated from one another genetically. Thus, the 1-to-82 region appears to contain a specific region that contributes to the transforming function of the protein. This segment operates by means other than the simple binding of pRb and/or p107.
Marsilio
E
E
Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115.
Cheng
S H
SH
Schaffhausen
B
B
Paucha
E
E
Livingston
D M
DM
D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000235:genetics* / Q000302:isolation & purification / Q000502:physiology; D015153:Blotting, Western; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D002872:Chromosome Deletion; D051379:Mice; D013539:Simian virus 40 / Q000235:genetics*
D000952:Antigens, Polyomavirus Transforming