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bioRxiv · 10.1101/433375

RNA polymerase I transcription fidelity, speed and processivity depend on the interplay of its lobe binding subunits

Tschochner, H.·Merkl, P. E.·Pilsl, M.·Fremter, T.·Längst, G.·Milkereit, P.·Griesenbeck, J.
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Abstract

Eukaryotic RNA polymerases I and III (Pol I and III) consist of core subunits, which are conserved in RNA polymerase II (Pol II). Additionally, Pol I and III have specific subunits, associating with the so-called lobe structure first described within Pol II. In Pol I of the yeast S. cerevisiae, these are Rpa34.5, and the N-terminal domains of Rpa49 and Rpa12.2, here referred to as the lobe-binding module (lb-module). We analyzed functions of the lb-module in a defined in vitro transcription system. Cooperation between lb-module components influenced transcription fidelity, elongation speed, and release of stalled Pol I complexes to continue elongation. Interestingly, lb-module containing Pol I and III, but not Pol II, were able to transcribe nucleosomal templates. Our data suggest, how the Pol I specific subunits may contribute to accurate and processive transcription of ribosomal RNA genes.

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Tschochner, H., Merkl, P. E., Pilsl, M., Fremter, T., Längst, G., Milkereit, P., Griesenbeck, J.. 2018-10-02. RNA polymerase I transcription fidelity, speed and processivity depend on the interplay of its lobe binding subunits. https://doi.org/10.1101/433375

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