Mediator is essential for small nuclear and nucleolar RNA transcription in yeast.

Fiche publication


Date publication

octobre 2018

Journal

Molecular and cellular biology

Auteurs

Membres identifiés du Cancéropôle Est :
Dr DEVYS Didier


Tous les auteurs :
Tourigny JP, Saleh MM, Schumacher K, Devys D, Zentner GE

Résumé

Eukaryotic RNA polymerase II (RNAPII) transcribes mRNA genes and non-protein coding RNA (ncRNA) genes including those encoding small nuclear and nucleolar RNAs (sn/snoRNAs). In metazoans, RNAPII transcription of sn/snoRNAs is facilitated by a number of specialized complexes, but no such complexes have been discovered in yeast. It has been proposed that yeast sn/snoRNA and mRNA expression relies on a set of common factors, but the extent to which regulators of mRNA genes function at yeast sn/snoRNA genes is unclear. Here, we investigated a potential role for the Mediator complex, essential for mRNA gene transcription, in sn/snoRNA gene transcription. We found that the Mediator maps to sn/snoRNA gene regulatory regions and that rapid depletion of the essential structural subunit Med14 strongly reduces RNAPII and TFIIB occupancy as well as nascent transcription of sn/snoRNA genes. Deletion of Med3 and Med15, subunits of the activator-interacting Mediator tail module, does not affect Mediator recruitment to, or RNAPII and TFIIB occupancy of, sn/snoRNA genes. Our analyses suggest that Mediator promotes PIC formation and transcription at sn/snoRNA genes, expanding the role of this critical regulator beyond its known functions in mRNA gene transcription and demonstrating further mechanistic similarity between the transcription of mRNA and sn/snoRNA genes.

Mots clés

Mediator, RNA polymerase II, snRNA, snoRNA

Référence

Mol. Cell. Biol.. 2018 Oct 1;: