A Molecular Titration System Coordinates Ribosomal Protein Gene Transcription with Ribosomal RNA Synthesis.
Cell growth potential is determined by the rate of ribosome biogenesis, a complex process that requires massive and coordinated transcriptional output. In the yeast Saccharomyces cerevisiae, ribosome biogenesis is highly regulated at the transcriptional level. Although evidence for a system that coordinates ribosomal RNA (rRNA) and ribosomal protein gene (RPG) transcription has been described, the molecular mechanisms remain poorly understood. Here we show that an interaction between the RPG transcriptional activator Ifh1 and the rRNA processing factor Utp22 serves to coordinate RPG transcription with that of rRNA. We demonstrate that Ifh1 is rapidly released from RPG promoters by a Utp22-independent mechanism following growth inhibition, but that its long-term dissociation requires Utp22. We present evidence that RNA polymerase I activity inhibits the ability of Utp22 to titrate Ifh1 from RPG promoters and propose that a dynamic Ifh1-Utp22 interaction fine-tunes RPG expression to coordinate RPG and rRNA transcription.
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Benjamin
B
Albert
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Britta
B
Knight
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Jason
J
Merwin
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Victoria
V
Martin
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Diana
D
Ottoz
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Yvonne
Y
Gloor
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland.
Maria Jessica
MJ
Bruzzone
Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA.
Adam
A
Rudner
Department of Molecular Biology and Institute for Genetics and Genomics in Geneva (iGE3), 30 quai Ernest-Ansermet, 1211 Geneva, Switzerland. Electronic address: david.shore@unige.ch.
David
D
Shore
D015966:Gene Expression Regulation, Fungal; D001678:Organelle Biogenesis; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012318:RNA Polymerase I / Q000235:genetics / Q000378:metabolism; D012335:RNA, Ribosomal / Q000096:biosynthesis / Q000235:genetics*; D012269:Ribosomal Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism; D015534:Trans-Activators / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic
C094046:IFH1 protein, S cerevisiae; D012335:RNA, Ribosomal; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; C588166:Utp22 protein, S cerevisiae; D012318:RNA Polymerase I
CURI complex; Ifh1; Saccharomyces cerevisiae; Utp22; ribosomal RNA; ribosomal protein gene; transcription; transcription factor titration