Insulin-stimulated tyrosine protein kinase. Characterization and relation to the insulin receptor.

Abstract

Utilizing histone phosphorylation as the basis for a quantitative assay, the insulin-stimulated protein kinase in human placenta has been characterized, The kinase copurifies through wheat germ agglutinin-Sepharose and DEAE-cellulose in constant ratio to the insulin binding function.Both activities are bound to the same extent on insulin-Sepharose, and the immobilized kinase, after extensive washing, exhibits activity versus histone, which closely approaches that of the insulin-stimulated, solubilized kinase.In addition, the bound kinase retains the ability to phosphorylate the