Cloning and activation of the Syrian hamster neu proto-oncogene.

Point mutations of the Syrian hamster neu proto-oncogene have been observed in the transmembrane domain of N-nitroso-N-ethylurea (ENU)-induced neurofibromas. Genomic DNA derived from tumor tissue showed transforming activity in an NIH 3T3 assay and a cDNA clone of the hamster neu gene, containing the entire protein-coding region, was isolated from a transformant cDNA library. The encoded product is 92 and 88% homologous to the rat neu and the human c-erbB-2, respectively. The product of the mutated hamster neu gene showed increased autophosphorylation of Tyr residues.