Expression of the mitochondrial genome in HeLa cells: XI. Isolation and characterization of transcription complexes of mitochondrial DNA

摘要: Abstract Transcription complexes of HeLa cell mitochondrial DNA have been isolated by sedimentation velocity in a sucrose gradient and buoyant density fractionation CsCl/ethidium bromide density-gradient characterized the electron microscope biochemical tests. Both open closed circular molecules carrying nascent RNA chains observed, with forms showing signs more intensive transcriptive activity terms number size attached to them. At least 25 bushes were counted same transcription complex. The largest estimated correspond as long whole molecule. observation that treatment protein denaturant such sodium dodecyl sulfate failed cause release from good part of, if not all, chains, strongly suggests base-paring, addition polymerase, has role holding together. Measurement rate labeling transcripts heavy light strands indicated two are transcribed at similar rate.