title: Glycogen synthase kinase-3 is involved in regulation of ribosome biogenesis in yeast.
abstract: Secretory defects cause transcriptional repression of both ribosomal proteins and ribosomal RNA genes in Saccharomyces cerevisiae. Rrs1, a trans-acting factor that participates in ribosome biogenesis, is involved in the signaling pathway induced by secretory defects. Here, we found that Rrs1 interacts with two homologs of the glycogen synthase kinase-3 (GSK-3), Rim11, and Mrk1. Rrs1 possesses a repetitive consensus amino acid sequence for phosphorylation by GSK-3, and mutation of this sequence abolished the interaction of Rrs1 with Rim11 and Mrk1. Although this mutation did not affect vegetative cell growth or secretory response, disruption of all four genes encoding GSK-3 homologs, especially Mck1, diminished the transcriptional repression of ribosomal protein genes in response to secretory defects. Among the four GSK-3 kinases, Mck1 appears to be the primary mediator of this response, while the other GSK-3 kinases contribute redundantly.
authors.affiliation: a Department of Biofunctional Science and Technology , Graduate School of Biosphere Science, Hiroshima University , Higashi-Hiroshima , Japan.
authors.forename: Yukari
authors.initials: Y
authors.lastname: Yabuki
authors.forename: Yushi
authors.initials: Y
authors.lastname: Kodama
authors.forename: Masako
authors.initials: M
authors.lastname: Katayama
authors.forename: Akiko
authors.initials: A
authors.lastname: Sakamoto
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Kanemaru
authors.forename: Kun
authors.initials: K
authors.lastname: Wan
authors.forename: Keiko
authors.initials: K
authors.lastname: Mizuta
mesh_terms: D017353:Gene Deletion; D038362:Glycogen Synthase Kinase 3 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D012269:Ribosomal Proteins / Q000235:genetics; D012270:Ribosomes / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D009687:Nuclear Proteins; C485770:RRS1 protein, S cerevisiae; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D038362:Glycogen Synthase Kinase 3; C068124:MCK1 protein, S cerevisiae
keywords: Mck1; Rrs1; glycogen synthase kinase-3 (GSK-3); ribosome synthesis; secretory defect