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Structural basis of TFIIIC-dependent RNA Polymerase III transcription initiation.

ABSTRACT: RNA Polymerase III (Pol III) is responsible for transcribing 5S ribosomal RNA (5S rRNA), tRNAs, and other short non-coding RNAs. Its recruitment to the 5S rRNA promoter requires transcription factors TFIIIA, TFIIIC, and TFIIIB. Here we use cryo-electron microscopy to visualize the S. cerevisiae complex of TFIIIA and TFIIIC bound to the promoter. Brf1-TBP binding further stabilizes the DNA, resulting in the full-length 5S rRNA gene wrapping around the complex. Our smFRET study reveals that the DNA undergoes both sharp bending and partial dissociation on a slow timescale, consistent with the model predicted from our cryo-EM results. Our findings provide new insights into the mechanism of how the transcription initiation complex assembles on the 5S rRNA promoter, a crucial step in Pol III transcription regulation.

SUBMITTER: Talyzina A

PROVIDER: S-EPMC10245719 | biostudies-literature | 2023 May

REPOSITORIES: biostudies-literature

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Structural basis of TFIIIC-dependent RNA Polymerase III transcription initiation.

Talyzina Anna A Han Yan Y Banerjee Chiranjib C Fishbain Susan S Reyes Alexis A Vafabakhsh Reza R He Yuan Y

bioRxiv : the preprint server for biology 20230516

RNA Polymerase III (Pol III) is responsible for transcribing 5S ribosomal RNA (5S rRNA), tRNAs, and other short non-coding RNAs. Its recruitment to the 5S rRNA promoter requires transcription factors TFIIIA, TFIIIC, and TFIIIB. Here we use cryo-electron microscopy to visualize the <i>S. cerevisiae</i> complex of TFIIIA and TFIIIC bound to the promoter. Brf1-TBP binding further stabilizes the DNA, resulting in the full-length 5S rRNA gene wrapping around the complex. Our smFRET study reveals that ...[more]

PMID: 37292922

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Structural basis of TFIIIC-dependent RNA polymerase III transcription initiation.

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