Oncogenic activation of p185neu stimulates tyrosine phosphorylation in vivo.

p185, the product of the neu/erbB2 proto-oncogene, is oncogenically activated by a point mutation that substitutes glutamic acid for valine in the transmembrane domain of the protein. We have found that the transforming form of p185 differs from its normal counterpart in inducing increased tyrosine phosphorylation of other proteins in vivo and in having a much shorter half-life. These results support the model that the transforming p185 resembles a ligand-activated receptor.