GENERATION OF pFastBacl-HT AND ISOLATION OF ErbB-2, ErbB-3 AND ErbB-4 cDNAs by RT-PCR
Over-expression of the ErbB receptor tyrosine kinase subfamily has been implicated in various types of human cancers. In the current study, ErbB-2, ErbB-3, and ErbB-4 tyrosine kinase domain cDNAs were isolated by RT-PCR and subcloned into a pFastBac-HT vector created through genetic engineering for the purpose of placing a his- tag on the ErbB protein receptors for purification. In isolating the ErbB-4 cDNA, an alternate receptor containing a 48 base-pair deletion in the tyrosine kinase region of the receptor was recovered. This result confirms an earlier report of an alternate splicing pattern in the ErbB-4 mRNA. Isolation of the ErbB TKD cDNAs allows for further research for the development of a diagnostic test of cancer tissues for over-expression of the ErbB receptors similar to the Herceptest, which tests for over-expression of ErbB-2.