Abstract
POLYOMA middle-T antigen is required for tumorigenesis in animals and for viral transformation of a variety of cells in culture (reviewed in ref. 1). Middle-T associates with and thereby activates p60c-src, a cellular tyrosine kinase homologous to the oncogene product of Rous sarcoma virus2,3. Activation of p60c-src by middle-T is accompanied both by dephosphorylation of tyrosine 527, a site which negatively regulates src kinase activity (reviewed in refs 4-6) and by autophosphorylation on tyrosine 416 (refs 7-10). Phosphoprotein p60c-src is subject to cell cycle-specific regulation. It is most active during mitosis and repressed in interphase11. Here we report that mitotic p60c-src is dephosphorylated at tyrosine 527. We also show that in cells expressing middle-T, src kinase activity is high both in mitosis and during interphase. An oncogenic mutant src protein, p60c-src(527F), where tyrosine 527 is substituted by phenylalanine, is also highly active in all phases of the cell cycle.
Original language | English (US) |
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Pages (from-to) | 431-433 |
Number of pages | 3 |
Journal | Nature |
Volume | 350 |
Issue number | 6317 |
DOIs | |
State | Published - 1991 |
Externally published | Yes |
ASJC Scopus subject areas
- General