Activation of murine T cells by antigen, antibodies binding the T cell antigen receptor, or
stimulatory anti-Thy-1 antibodies results in rapid phosphorylation of the T cell receptor f
chain on tyrosine residues. The T cell receptor is itself unlikely to be a tyrosine kinase;
rather, it is probable that this receptor is coupled to a nonreceptor tyrosine kinase. To
understand further this protein kinase pathway, additional targets of the tyrosine kinase have
been sought by comparing antiphosphotyrosine antibody immunoblots of cellular proteins …