PROCESS FOR DETERMINING THE ACTIVITY OF SPECIFIC PHOSPHOTYROSINE PHOSPHATASES AND SPECIFIC EFFECTORS THEREOF IN INTACT CELLS

摘要

In order to determine the activity of a specific protein tyrosine phosphatase (PTPase) in intact cells, intact cells that contain a substrate of the specific PTPase are incubated, optionally after stimulating substrate phosphorylation, with a substance capable of entering the intact cells and selectively inhibiting phosphorylation of the substrate. The phosphorylation degree of the substrate is measured if required several times at different moments in time and the activity of the specific PTPase is determined from the measured phosphorylation degree of the substrate. In order to determine the effectors of the specific PTPase, an additional measurement is carried out in the presence of a test substance and the effector activity of the test substance is determined by comparing the various phosphorylation degrees.