Phosphatidylinositol kinase type I activity associates with various oncogene products.

Published

Journal Article

We have assayed immunoprecipitates of several oncogene products from retrovirally infected chicken embryo fibroblasts (CEF) for phosphatidylinositol (PI) kinase activity. Immunoprecipitates of P68gag-ros, P130gag-tps, P47gag-crk, polyoma middle T (mT)-p60c-src complex, and mT-p62c-yrs complex exhibited PI kinase activity when assayed without detergents. This activity was sensitive to the nonionic detergent, Triton X-100, and the product was indistinguishable from phosphatidylinositol-3-phosphate, the product of kinase type I. Immunoprecipitates of p21Ha-ros protein did not contain any PI kinase type I activity. It has been suggested that an 81 kD protein phosphorylated in in vitro kinase assays of immunoprecipitates from mT-transformed rodent cells is responsible for the PI kinase type I activity seen in these immunoprecipitates. We have detected a chicken homologue of this 81 kD protein in immunoprecipitates of lysates from mT-transformed CEF. However, the chicken 81 kD protein sedimented more quickly than the PI kinase activity in sucrose gradients. In addition, the 81 kD protein was not detectable in protein kinase assays of immunoprecipitates of P68gag-ros or P130gag-fps. These results suggest that the 81 kD protein may not be the PI kinase.

Full Text

Duke Authors

Cited Authors

  • Fukui, Y; Kornbluth, S; Jong, SM; Wang, LH; Hanafusa, H

Published Date

  • January 1989

Published In

Volume / Issue

  • 4 / 4

Start / End Page

  • 283 - 292

PubMed ID

  • 2549489

Pubmed Central ID

  • 2549489

International Standard Serial Number (ISSN)

  • 0890-6467

Language

  • eng