Inhibitory Tyrosine Protein Kinase p50 Is Associated with Protein-tyrosine Phosphatase PTP-PEST in Hemopoietic and Non-hemopoietic Cells

Interleukin-3 induces association of the protein-tyrosine phosphatase SHP2 and phosphatidylinositol 3-kinase with a 100-kDa tyrosine-phosphorylated protein in hemopoietic cells.

We have observed previously the co-immunoprecipitation of the p85 subunit of phosphatidylinositol-3 kinase (PI3K) and SHP2 in murine lymphohemopoietic cells after stimulation with interleukin-3. We have investigated this interaction in more detail and now report the identification of a potentially novel 100-kDa protein (termed p100), which is inducibly phosphorylated on tyrosine after interleuk...

Activation of the Abelson tyrosine kinase activity is associated with suppression of apoptosis in hemopoietic cells.

A chromosomal translocation uniquely associated with chronic myeloid leukemia leads to the formation of a chimeric gene, bcr-abl, on the Philadelphia chromosome. The BRC-ABL protein displays an uncontrolled tyrosine kinase activity similar to that seen with the transforming oncogene of the Abelson murine leukemia (ABL) virus (v-abl). An interleukin 3 dependent cell line, IC.DP, has been transfe...

Activation of the Abelson Tyrosine Kinase Activity Is Associated with Suppression of Apoptosis in Hemopoietic Cells1

A chromosomal translocation uniquely associated with chronic myeloid leukemia leads to the formation of a chimeric gene, bcr-abl, on the Phil adelphia chromosome. The BRC-ABL protein displays an uncontrolled tyrosine kinase activity similar to that seen with the transforming onco gene of the Abelson murine leukemia (ABL) virus (\-abl). An interleukin 3 dependent cell line, IC.DP, has been trans...

Phosphatase (PTP)-PEST Activation via Linkage to Protein Tyrosine CD2BP1 Modulates CD2-Dependent T Cell

Identification of p130(cas) as a substrate for the cytosolic protein tyrosine phosphatase PTP-PEST.

PTP-PEST is a ubiquitously expressed, cytosolic, mammalian protein tyrosine phosphatase (PTP) which exhibits high specific activity in vitro. We have investigated the substrate specificity of PTP-PEST by a novel substrate-trapping approach in combination with in vitro dephosphorylation experiments. We initially identified a prominent 130-kDa tyrosine-phosphorylated protein in pervanadate-treate...