Stimulation of tyrosine phosphorylation in lectin treated human lymphocytes.

摘要: Large increases in tyrosine phosphorylation have been detected subcellular matrixes isolated from lectin treated human lymphocytes. In stimulated cells proteins of molecular weight 105, 75, 58 and 35 kDa contained phosphotyrosine (P-tyr) whereas non-stimulated had no 105 low levels P-tyr kDa. increased kinase activity was also shown using gastrin as substrate. both the phosphoprotein most heavily labelled, after partial proteolysis different phosphopeptides were generated. A peptide with a sequence analogous to autophosphorylated site pp60src inhibited cells. The lymphocyte system provides useful tool study normal protein kinases their role cellular proliferation.