title: CTD kinase I is involved in RNA polymerase I transcription.
abstract: RNA polymerase II carboxy terminal domain (CTD) kinases are key elements in the control of mRNA synthesis. Yeast CTD kinase I (CTDK-I), is a non-essential complex involved in the regulation of mRNA synthesis at the level of transcription elongation, pre-mRNA 3' formation and nuclear export. Here, we report that CTDK-I is also involved in ribosomal RNA synthesis. We show that CTDK-I is localized in part in the nucleolus. In its absence, nucleolar structure and RNA polymerase I transcription are affected. In vitro experiments show an impairment of the Pol I transcription machinery. Remarkably, RNA polymerase I co-precipitates from cellular extracts with Ctk1, the kinase subunit of the CTDK-I complex. In vitro analysis further demonstrates a direct interaction between RNA polymerase I and Ctk1. The results suggest that CTDK-I might participate in the regulation of distinct nuclear transcriptional machineries, thus playing a role in the adaptation of the global transcriptional response to growth signalling.
authors.affiliation: Service de Biochimie et Génétique Moléculaire, CEA/Saclay, 91191 Gif/Yvette, France.
authors.forename: Céline
authors.initials: C
authors.lastname: Bouchoux
authors.forename: Guillaume
authors.initials: G
authors.lastname: Hautbergue
authors.forename: Sabrina
authors.initials: S
authors.lastname: Grenetier
authors.forename: Christophe
authors.initials: C
authors.lastname: Carles
authors.forename: Michel
authors.initials: M
authors.lastname: Riva
authors.forename: Valérie
authors.initials: V
authors.lastname: Goguel
mesh_terms: D002466:Cell Nucleolus / Q000737:chemistry / Q000648:ultrastructure; D009097:Multienzyme Complexes / Q000032:analysis; D009154:Mutation; D011494:Protein Kinases / Q000032:analysis / Q000235:genetics / Q000502:physiology*; D012318:RNA Polymerase I / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D009097:Multienzyme Complexes; D011494:Protein Kinases; C060137:carboxy-terminal domain kinase; D012318:RNA Polymerase I