Induction and characterization of tyrosine aminotransferase and its mRNA isolated from D. hydei salivary glands
Belew, Karla Jean Davidson
MetadataShow full item record
A puff at band II-48C on the salivary gland polytene chromosomes of D_. hydei is induced by pyridoxine. Pyridoxine also induces a 40,000. protein and tyrosine aminotransferase activity. Tyrosine aminotransferase (TAT) was purified and used to prepare antibody in rabbits. The anti-TAT immunoprecipitated the newly synthesized 40,000 D. polypeptide. TAT mRNA containing polysomes were immunoprecipitated. The TAT mRNA was translated in an in vitro translation system. The polypeptide translated had a molecular weight of 40,000 D. and was nuncprecipitated by anti-TAT. Tritiated RNA extracted from TAT mRNA containinq polysomes was in situ hybridized to D. hydei salivary gland squashes. Silver grains were found over the nucleolus and band II-48C. These data identify II-48C as the locus coding for TAT.