Several aspects of total genomic DNA transcription in a HeLa cell extract.

Several aspects of total genomic DNA transcription in a HeLa cell extract were described. (1) By using in vitro transcripts from total genomic DNA as probes, we elucidated several structures of short interspersed elements which are transcribed by RNA polymerase III (designated as Pol III/SINEs. (2) To know whether the repetitive sequence we cloned and sequenced comprises a major or minor family, we developed in vitro run-off transcription assay of total genomic DNA. (3) Unlike in vitro transcription of total genomic DNA from vertebrates, major in vitro transcripts from macronuclear total DNA of Tetrahymena were found to be tRNA themselves.