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Yeast Rrn7 and human TAF1B are TFIIB-related RNA polymerase I general transcription factors.

ABSTRACT: Eukaryotic and archaeal multisubunit RNA polymerases (Pols) are structurally related and require several similar components for transcription initiation. However, none of the Pol I factors were known to share homology with transcription factor IIB (TFIIB) or TFIIB-related proteins, key factors in the initiation mechanisms of the other Pols. Here we show that Rrn7, a subunit of the yeast Pol I core factor, and its human ortholog TAF1B are TFIIB-like factors. Although distantly related, Rrn7 shares many activities associated with TFIIB-like factors. Domain swaps between TFIIB-related factors show that Rrn7 is most closely related to the Pol III general factor Brf1. Our results point to the conservation of initiation mechanisms among multisubunit Pols and reveal a key function of yeast core factor/human SL1 in Pol I transcription.

SUBMITTER: Knutson BA

PROVIDER: S-EPMC3319074 | biostudies-literature | 2011 Sep

REPOSITORIES: biostudies-literature

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Yeast Rrn7 and human TAF1B are TFIIB-related RNA polymerase I general transcription factors.

Knutson Bruce A BA Hahn Steven S

Science (New York, N.Y.) 20110901 6049

Eukaryotic and archaeal multisubunit RNA polymerases (Pols) are structurally related and require several similar components for transcription initiation. However, none of the Pol I factors were known to share homology with transcription factor IIB (TFIIB) or TFIIB-related proteins, key factors in the initiation mechanisms of the other Pols. Here we show that Rrn7, a subunit of the yeast Pol I core factor, and its human ortholog TAF1B are TFIIB-like factors. Although distantly related, Rrn7 share ...[more]

PMID: 21921198

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Dataset Information

Yeast Rrn7 and human TAF1B are TFIIB-related RNA polymerase I general transcription factors.

Publications

Yeast Rrn7 and human TAF1B are TFIIB-related RNA polymerase I general transcription factors.

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