Nuclear beta-globin RNA transcripts initiated in vitro with gamma-thio nucleoside triphosphate.

We have been able to obtain significant levels of apparently in vitro-initiated beta-globin transcripts from isolated nuclei using mouse Friend cells. The level of hybrid selected beta-globin transcripts was increased 3-9-fold in nuclei after the cells were induced with dimethylsulfoxide. The newly initiated transcripts were detected through incorporation of gamma-thio ATP and isolation by Hg-agarose chromatography. The 5'-terminus was identified by recovery of the thio tetraphosphate in hydrolysis products from in vitro initiated RNA using gamma-35S ATP.