| Autor: |
Freund GG; Department of Pathology and Laboratory Medicine, University of Rochester School of Medicine and Dentistry, New York 14642., Wittig JG, Mooney RA |
| Jazyk: |
angličtina |
| Zdroj: |
Biochemical and biophysical research communications [Biochem Biophys Res Commun] 1995 Jan 05; Vol. 206 (1), pp. 272-8. |
| DOI: |
10.1006/bbrc.1995.1038 |
| Abstrakt: |
Insulin receptor tyrosine kinase activity accounts for tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1), but the serine kinase(s) responsible for serine phosphorylation of IRS-1 is(are) unknown. In vitro kinase assays performed on PI3-kinase and IRS-1 immunoprecipitates demonstrated insulin-dependent serine phosphorylation of IRS-1. IRS-1 was associated with both insulin-dependent and independent serine kinases. Only the insulin-dependent serine kinase preferred Mn2+ over Mg2+ and was recovered from cell lysates containing dithiothreitol. In complexes of tyrosine phosphorylated recombinant IRS-1 and PI3-kinase, phosphorylation of IRS-1 was associated with decreased phosphorylation of the p85 subunit of PI3-kinase. These results are consistent with PI3-kinase being responsible for insulin-dependent serine phosphorylation of IRS-1 and suggest that this phosphorylation reaction may affect functions of both IRS-1 and the PI3-kinase. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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