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bioRxiv · 10.1101/2021.08.27.457903

An integrated model for termination of RNA polymerase III transcription

Xie, J.·Aiello, U.·Clement, Y.·Haidara, N.·Girbig, M.·Schmitzova, J.·Pena, V.·Muller, C. W.·Libri, D.·Porrua, O.
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Abstract

RNA polymerase III (RNAPIII) synthesizes essential and abundant non-coding RNAs such as tRNAs. Controlling RNAPIII span of activity by accurate and efficient termination is a challenging necessity to ensure robust gene expression and to prevent conflicts with other DNA-associated machineries. The mechanism of RNAPIII termination is believed to be simpler than that of other eukaryotic RNA polymerases, solely relying on the recognition of a T-tract in the non-template strand. Here we combine high-resolution genome-wide analyses and in vitro transcription termination assays to revisit the mechanism of RNAPIII transcription termination in budding yeast. We show that T-tracts are necessary but not always sufficient for termination and that secondary structures of the nascent RNAs are important auxiliary cis-acting elements. Moreover, we show that the helicase Sen1 plays a key role in a fail-safe termination pathway. Our results provide a comprehensive model illustrating how multiple mechanisms cooperate to ensure efficient RNAPIII transcription termination.

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Xie, J., Aiello, U., Clement, Y., Haidara, N., Girbig, M., Schmitzova, J., Pena, V., Muller, C. W., Libri, D., Porrua, O.. 2021-08-28. An integrated model for termination of RNA polymerase III transcription. https://doi.org/10.1101/2021.08.27.457903

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