CTD kinase I is involved in RNA polymerase I transcription.
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.
Bouchoux
Céline
C
Service de Biochimie et Génétique Moléculaire, CEA/Saclay, 91191 Gif/Yvette, France.
Hautbergue
Guillaume
G
Grenetier
Sabrina
S
Carles
Christophe
C
Riva
Michel
M
Goguel
Valérie
V
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
D009097:Multienzyme Complexes; D011494:Protein Kinases; C060137:carboxy-terminal domain kinase; D012318:RNA Polymerase I