The U6 gene of Saccharomyces cerevisiae is transcribed by RNA polymerase C (III) in vivo and in vitro.
Unlike the majority of genes encoding small nuclear RNAs, which are transcribed by RNA polymerase B, the U6 gene contains features found in both class B and class C genes, indicating the involvement of a combination of transcription factors normally specific to each class of genes. We present direct genetic and biochemical evidence that the U6 gene of Saccharomyces cerevisiae is transcribed by RNA polymerase C in vivo as well as in vitro. A mutant strain with a temperature-sensitive defect in the large subunit of RNA polymerase C that results in defective transcription of tRNA and 5S RNA genes shows a corresponding defect in U6 RNA levels. Also, purified RNA polymerase C transcribes the U6 gene when supplemented with partially purified TFIIIB. The other class C transcription factors, TFIIIA and Tau (TFIIIC), are not required in this system.
Département de Biologie, CEN de Saclay, Commissariat à l'Energie Atomique, Gif sur Yvette, France.
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Moenne
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Camier
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Anderson
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Margottin
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Beggs
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Sentenac
D001483:Base Sequence; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization; D012320:RNA Polymerase III / Q000378:metabolism*; D012341:RNA, Ribosomal, 5S / Q000235:genetics; D012342:RNA, Small Nuclear / Q000235:genetics*; D012343:RNA, Transfer / Q000235:genetics; D015183:Restriction Mapping; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D015719:Single-Strand Specific DNA and RNA Endonucleases; D035361:Transcription Factor TFIIIB; D014157:Transcription Factors / Q000494:pharmacology; D014158:Transcription, Genetic
D012341:RNA, Ribosomal, 5S; D012342:RNA, Small Nuclear; D035361:Transcription Factor TFIIIB; D014157:Transcription Factors; D012343:RNA, Transfer; D012321:DNA-Directed RNA Polymerases; D012320:RNA Polymerase III; D015719:Single-Strand Specific DNA and RNA Endonucleases