title: GAR1 is an essential small nucleolar RNP protein required for pre-rRNA processing in yeast.
abstract: Among the few proteins of the eukaryotic nucleolus that have been characterized, four proteins, nucleolin, fibrillarin, SSB1 and NSR1, possess a common structural motif, the GAR domain, which is rich in glycine and arginine residues. In order to examine whether the presence of this domain is characteristic of a family of nucleolar proteins, we investigated whether other yeast genes encode proteins containing GAR domains. We report here the sequence and the characterization of a new yeast gene, GAR1, which encodes a protein of 205 residues containing two GAR domains. GAR1 is a non-ribosomal protein, localized in the yeast nucleolus, which is essential for cell growth. Immunoprecipitation with anti-GAR1 antibodies shows that GAR1 is associated with a subset of snoRNAs, including snR10 and snR30. Depletion of GAR1 by expression under the control of a regulated GAL promoter, impairs processing of the 35S primary transcript of pre-rRNA and prevents synthesis of 18S rRNA. GAR1 is thus the fifth member of a family of nucleolar proteins containing GAR domains, and is involved in rRNA metabolism.
authors.affiliation: CRBGC du CNRS, Toulouse, France.
authors.forename: J P
authors.initials: JP
authors.lastname: Girard
authors.forename: H
authors.initials: H
authors.lastname: Lehtonen
authors.forename: M
authors.initials: M
authors.lastname: Caizergues-Ferrer
authors.forename: F
authors.initials: F
authors.lastname: Amalric
authors.forename: D
authors.initials: D
authors.lastname: Tollervey
authors.forename: B
authors.initials: B
authors.lastname: Lapeyre
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015139:Blotting, Southern; D003001:Cloning, Molecular; D004271:DNA, Fungal / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000235:genetics; D005656:Fungal Proteins / Q000235:genetics*; D005800:Genes, Fungal; D008969:Molecular Sequence Data; D005810:Multigene Family; D009687:Nuclear Proteins / Q000235:genetics*; D012322:RNA Precursors / Q000235:genetics*; D012323:RNA Processing, Post-Transcriptional; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D015183:Restriction Mapping; D012261:Ribonucleoproteins / Q000235:genetics* / Q000378:metabolism*; D017411:Ribonucleoproteins, Small Nuclear; D020718:Ribonucleoproteins, Small Nucleolar; D012270:Ribosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D009687:Nuclear Proteins; D012322:RNA Precursors; D011993:Recombinant Fusion Proteins; D012261:Ribonucleoproteins; D017411:Ribonucleoproteins, Small Nuclear; D020718:Ribonucleoproteins, Small Nucleolar; D029701:Saccharomyces cerevisiae Proteins; C073180:GAR1 protein, S cerevisiae; D001616:beta-Galactosidase