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Structural basis for RNA polymerase III transcription repression by Maf1.

ABSTRACT: Maf1 is a conserved inhibitor of RNA polymerase III (Pol III) that influences phenotypes ranging from metabolic efficiency to lifespan. Here, we present a 3.3-Å-resolution cryo-EM structure of yeast Maf1 bound to Pol III, establishing that Maf1 sequesters Pol III elements involved in transcription initiation and binds the mobile C34 winged helix 2 domain, sealing off the active site. The Maf1 binding site overlaps with that of TFIIIB in the preinitiation complex.

SUBMITTER: Vorlander MK

PROVIDER: S-EPMC7104376 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature

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Structural basis for RNA polymerase III transcription repression by Maf1.

Vorländer Matthias K MK Baudin Florence F Moir Robyn D RD Wetzel René R Hagen Wim J H WJH Willis Ian M IM Müller Christoph W CW

Nature structural & molecular biology 20200217 3

Maf1 is a conserved inhibitor of RNA polymerase III (Pol III) that influences phenotypes ranging from metabolic efficiency to lifespan. Here, we present a 3.3-Å-resolution cryo-EM structure of yeast Maf1 bound to Pol III, establishing that Maf1 sequesters Pol III elements involved in transcription initiation and binds the mobile C34 winged helix 2 domain, sealing off the active site. The Maf1 binding site overlaps with that of TFIIIB in the preinitiation complex. ...[more]

PMID: 32066962

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