Tyrosine phosphorylation within the amino-terminal domain of pp60c-src molecules associated with polyoma virus middle-sized tumor antigen.
AUTOR(ES)
Yonemoto, W
RESUMO
We have examined the in vitro phosphorylation of cellular src protein (pp60c-src) molecules associated with the polyoma virus middle-sized tumor antigen in polyoma virus-transformed cells. These pp60c-src molecules possessed an enhanced tyrosyl kinase activity, migrated aberrantly on NaDodSO4/polyacrylamide gels, and contained a novel site of tyrosine phosphorylation within the amino-terminal region of the molecule. The pp60c-src molecules not associated with the middle-sized tumor antigen were phosphorylated exclusively on a tyrosine residue within the carboxyl-terminal domain of pp60c-src. A similar modified form of the middle-sized tumor antigen-associated pp60c-src protein was detected in lysates from polyoma virus-transformed cells labeled in vivo with [32P]orthophosphate in the presence of sodium orthovanadate, an inhibitor of phosphotyrosyl phosphatases.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=390426Documentos Relacionados
- Altered sites of tyrosine phosphorylation in pp60c-src associated with polyomavirus middle tumor antigen.
- Increased pp60c-src tyrosyl kinase activity in human neuroblastomas is associated with amino-terminal tyrosine phosphorylation of the src gene product.
- Structural and functional modification of pp60c-src associated with polyoma middle tumor antigen from infected or transformed cells.
- Mapping of the amino-terminal half of polyomavirus middle-T antigen indicates that this region is the binding domain for pp60c-src.
- Transformation by polyoma virus is drastically reduced by substitution of phenylalanine for tyrosine at residue 315 of middle-sized tumor antigen.
