AN UNEXPECTED TRANSFORMING GENE IN CALF-THYMUS CARRIER DNA - BOVINE HST

During a search for transforming genes by transfecting a human cDNA ex pression library together with calf thymus carrier-DNA into NIH/3T3 ce lls, we found a focus which was induced by a plasmid containing a sequ ence highly homologous to human HST (a transforming gene from Human ST omach cancer). However, PCR analysis identified the source of this seq uence as calf thymus DNA. The deduced amino acid (aa) sequence of bovi ne HST shows 91 and 81% identity to the human and mouse HST aa sequenc es, respectively. These data suggest that the hst of calf thymus carri er-DNA could induce transformation of NIH/3T3 cells.