Relationship of phosphorylation to the oligomerization of SV40 T antigen and its association with p53.

The potential significance of the phosphorylation of SV40 large T antigen for oligomers and complexes with the cellular protein p53 was investigated. We observed that T antigen oligomers remain stable after enzymatic dephosphorylation by alkaline phosphatase up to 80%. Separate analysis of free and p53-bound T antigen revealed a considerably lower phosphorylation of the p53-bound subclass. Therefore, a simple correlation between the overall phosphorylation of T antigen and the formation of oligomers and T-p53 complexes is highly unlikely.