Insulin receptor has tyrosine kinase activity toward Shc in rat liver

Autor: E.V. Páez-Espinosa, C.R.O. Carvalho, L.A. Velloso, M.J.A. Saad
Jazyk: angličtina
Rok vydání: 1998
Předmět:
Zdroj: Brazilian Journal of Medical and Biological Research, Vol 31, Iss 11, Pp 1415-1419 (1998)
Druh dokumentu: article
ISSN: 0100-879X
1414-431X
DOI: 10.1590/S0100-879X1998001100008
Popis: Insulin induces tyrosine phosphorylation of Shc in cell cultures and in insulin-sensitive tissues of the intact rat. However, the ability of insulin receptor (IR) tyrosine kinase to phosphorylate Shc has not been previously demonstrated. In the present study, we investigated insulin-induced IR tyrosine kinase activity towards Shc. Insulin receptor was immunoprecipitated from liver extracts, before and after a very low dose of insulin into the portal vein, and incubated with immunopurified Shc from liver of untreated rats. The kinase assay was performed in vitro in the presence of exogenous ATP and the phosphorylation level was quantified by immunoblotting with antiphosphotyrosine antibody. The results demonstrate that Shc interacted with insulin receptor after infusion of insulin, and, more important, there was insulin receptor kinase activity towards immunopurified Shc. The description of this pathway in animal tissue may have an important role in insulin receptor tyrosine kinase activity toward mitogenic transduction pathways.
Databáze: Directory of Open Access Journals