Synergistic defect in 60S ribosomal subunit assembly caused by a mutation of Rrs1p, a ribosomal protein L11-binding protein, and 3'-extension of 5S rRNA in Saccharomyces cerevisiae

Ribosomal protein L1 from Saccharomyces cerevisiae binds 5S rRNA and can be released from intact 60S ribosomal subunits as an L1-5S ribonucleoprotein (RNP) particle. To understand the nature of the interaction between L1 and 5S rRNA and to assess the role of L1 in ribosome assembly and function, we cloned the RPL1 gene encoding L1. We have shown that RPL1 is an essential single-copy gene. A conditional null mutant in which the only copy of RPL1 is under control of the repressible GAL1 promoter was constructed. Depletion of L1 causes instability of newly synthesized 5S rRNA in vivo. Cells depleted of L1 no longer assemble 60S ribosomal subunits, indicating that L1 is required for assembly of stable 60S ribosomal subunits but not 40S ribosomal subunits. An L1-5S RNP particle not associated with ribosomal particles was detected by coimmunoprecipitation of L1 and 5S rRNA. This pool of L1-5S RNP remained stable even upon cessation of 60S ribosomal subunit assembly by depletion of another ribosomal protein, L16. Preliminary results suggest that transcription of RPL1 is not autogenously regulated by L1.

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Molecular genetics of cryptopleurine resistance in Saccharomyces cerevisiae: expression of a ribosomal protein gene family.

Genetics ◽

10.1093/genetics/135.3.719 ◽

1993 ◽

Vol 135 (3) ◽

pp. 719-730

Author(s):

A G Paulovich ◽

J R Thompson ◽

J C Larkin ◽

Z Li ◽

J L Woolford

Keyword(s):

Saccharomyces Cerevisiae ◽

Ribosomal Protein ◽

Gene Fusion ◽

Null Allele ◽

Ribosomal Subunit ◽

Null Alleles ◽

Protein Synthesis Inhibitor ◽

Lacz Gene ◽

Ribosomal Subunits ◽

Cry1 Gene

Abstract The Saccharomyces cerevisiae CRY1 gene encodes the 40S ribosomal subunit protein rp59 and confers sensitivity to the protein synthesis inhibitor cryptopleurine. A yeast strain containing the cry1-delta 1::URA3 null allele is viable, cryptopleurine sensitive (CryS), and expresses rp59 mRNA, suggesting that there is a second functional CRY gene. The CRY2 gene has been isolated from a yeast genomic library cloned in bacteriophage lambda, using a CRY1 DNA probe. The DNA sequence of the CRY2 gene contains an open reading frame encoding ribosomal protein 59 that differs at five residues from rp59 encoded by the CRY1 gene. The CRY2 gene was mapped to the left arm of chromosome X, centromere-proximal to cdc6 and immediately adjacent to ribosomal protein genes RPS24A and RPL46. Ribosomal protein 59 is an essential protein; upon sporulation of a diploid doubly heterozygous for cry1-delta 2::TRP1 cry2-delta 1::LEU2 null alleles, no spore clones containing both null alleles were recovered. Several results indicate that CRY2 is expressed, but at lower levels than CRY1: (1) Introduction of CRY2 on high copy plasmids into CryR yeast of genotype cry1 CRY2 confers a CryS phenotype. Transformation of these CryR yeast with CRY2 on a low copy CEN plasmid does not confer a CryS phenotype. (2) Haploids containing the cry1-delta 2::TRP1 null allele have a deficit of 40S ribosomal subunits, but cry2-delta 1::LEU2 strains have wild-type amounts of 40S ribosomal subunits. (3) CRY2 mRNA is present at lower levels than CRY1 mRNA. (4) Higher levels of beta-galactosidase are expressed from a CRY1-lacZ gene fusion than from a CRY2-lacZ gene fusion. Mutations that alter or eliminate the last amino acid of rp59 encoded by either CRY1 or CRY2 result in resistance to cryptopleurine. Because CRY2 (and cry2) is expressed at lower levels than CRY1 (and cry1), the CryR phenotype of cry2 mutants is only expressed in strains containing a cry1-delta null allele.

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The GTP-binding Protein YlqF Participates in the Late Step of 50 S Ribosomal Subunit Assembly inBacillus subtilis

Journal of Biological Chemistry ◽

10.1074/jbc.m512556200 ◽

2006 ◽

Vol 281 (12) ◽

pp. 8110-8117 ◽

Cited By ~ 60

Author(s):

Yoshitaka Matsuo ◽

Takuya Morimoto ◽

Masayoshi Kuwano ◽

Pek Chin Loh ◽

Taku Oshima ◽

...

Keyword(s):

Binding Protein ◽

Ribosomal Subunit ◽

Gtp Binding Protein ◽

Subunit Assembly ◽

Gtp Binding ◽

Late Step

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Developmental expression and 5S rRNA-binding activity of Xenopus laevis ribosomal protein L5

Molecular and Cellular Biology ◽

10.1128/mcb.9.12.5281-5288.1989 ◽

1989 ◽

Vol 9 (12) ◽

pp. 5281-5288

Author(s):

W M Wormington

Keyword(s):

Ribosomal Protein ◽

Mammalian Cells ◽

Ribosomal Proteins ◽

5S Rrna ◽

Yeast Cells ◽

Developmental Expression ◽

Rrna Synthesis ◽

Ribosome Assembly ◽

Subunit Assembly ◽

Ribosomal Protein L5

Ribosomal protein L5 binds specifically to 5S rRNA to form a complex that is a precursor to 60S subunit assembly in vivo. Analyses in yeast cells, mammalian cells, and Xenopus embryos have shown that the accumulation of L5 is not coordinated with the expression of other ribosomal proteins. In this study, the primary structure and developmental expression of Xenopus ribosomal protein L5 were examined to determine the basis for its distinct regulation. These analyses showed that L5 expression could either coincide with 5S rRNA synthesis and ribosome assembly or be controlled independently of these events at different stages of Xenopus development. L5 synthesis during oogenesis was uncoupled from the accumulation of 5S rRNa but coincided with subunit assembly. In early embryos, the inefficient translation of L5 mRNA resulted in the accumulation of a stable L5-5S rRNA complex before ribosome assembly at later stages of development. Additional results demonstrated that L5 protein synthesized in vitro bound specifically to 5S rRNA.

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Developmental expression and 5S rRNA-binding activity of Xenopus laevis ribosomal protein L5.

Molecular and Cellular Biology ◽

10.1128/mcb.9.12.5281 ◽

1989 ◽

Vol 9 (12) ◽

pp. 5281-5288 ◽

Cited By ~ 35

Author(s):

W M Wormington

Keyword(s):

Ribosomal Protein ◽

Mammalian Cells ◽

Ribosomal Proteins ◽

5S Rrna ◽

Yeast Cells ◽

Developmental Expression ◽

Rrna Synthesis ◽

Ribosome Assembly ◽

Subunit Assembly ◽

Ribosomal Protein L5

Ribosomal protein L5 binds specifically to 5S rRNA to form a complex that is a precursor to 60S subunit assembly in vivo. Analyses in yeast cells, mammalian cells, and Xenopus embryos have shown that the accumulation of L5 is not coordinated with the expression of other ribosomal proteins. In this study, the primary structure and developmental expression of Xenopus ribosomal protein L5 were examined to determine the basis for its distinct regulation. These analyses showed that L5 expression could either coincide with 5S rRNA synthesis and ribosome assembly or be controlled independently of these events at different stages of Xenopus development. L5 synthesis during oogenesis was uncoupled from the accumulation of 5S rRNa but coincided with subunit assembly. In early embryos, the inefficient translation of L5 mRNA resulted in the accumulation of a stable L5-5S rRNA complex before ribosome assembly at later stages of development. Additional results demonstrated that L5 protein synthesized in vitro bound specifically to 5S rRNA.

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Ribosomal protein L32 of Saccharomyces cerevisiae influences both the splicing of its own transcript and the processing of rRNA.

Molecular and Cellular Biology ◽

10.1128/mcb.17.4.1959 ◽

1997 ◽

Vol 17 (4) ◽

pp. 1959-1965 ◽

Cited By ~ 92

Author(s):

J Vilardell ◽

J R Warner

Keyword(s):

Saccharomyces Cerevisiae ◽

Ribosomal Protein ◽

Ribosomal Subunit ◽

Mutant Gene ◽

Mutant Form ◽

Hydrophobic Domain ◽

Rna Molecules ◽

Reduced Rate ◽

And Function ◽

Isoleucine Residue

Ribosomal protein L32 of Saccharomyces cerevisiae binds to and regulates the splicing and the translation of the transcript of its own gene. Selecting for mutants deficient in the regulation of splicing, we have identified a mutant form of L32 that no longer binds to the transcript of RPL32 and therefore does not regulate its splicing. The mutation is the deletion of an isoleucine residue from a highly conserved hydrophobic domain near the middle of L32. The mutant protein supports growth, at a reduced rate, and is found at normal levels in mature ribosomes. However, in cells homozygous for the mutant gene, the rate of processing of the ribosomal RNA component of the 60S ribosomal subunit is severely reduced, leading to an insufficiency of 60S subunits. L32 must be considered a remarkable protein. Composed of only 104 amino acids, it appears to interact with three distinct RNA molecules to influence three different elements of RNA processing and function in three different locations of the cell: the processing of pre-rRNA in the nucleolus, the splicing of the RPL32 transcript in the nucleus, and the translation of the spliced RPL32 mRNA in the cytoplasm.

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Mapping of the Saccharomyces cerevisiae Oxa1-Mitochondrial Ribosome Interface and Identification of MrpL40, a Ribosomal Protein in Close Proximity to Oxa1 and Critical for Oxidative Phosphorylation Complex Assembly

Eukaryotic Cell ◽

10.1128/ec.00219-09 ◽

2009 ◽

Vol 8 (11) ◽

pp. 1792-1802 ◽

Cited By ~ 37

Author(s):

Lixia Jia ◽

Jasvinder Kaur ◽

Rosemary A. Stuart

Keyword(s):

Saccharomyces Cerevisiae ◽

Oxidative Phosphorylation ◽

Ribosomal Protein ◽

Ribosomal Proteins ◽

Close Association ◽

Ribosomal Subunit ◽

Inner Membrane ◽

Mitochondrial Inner Membrane ◽

Mitochondrial Ribosome ◽

Encoded Proteins

ABSTRACT The Oxa1 protein plays a central role in facilitating the cotranslational insertion of the nascent polypeptide chains into the mitochondrial inner membrane. Mitochondrially encoded proteins are synthesized on matrix-localized ribosomes which are tethered to the inner membrane and in physical association with the Oxa1 protein. In the present study we used a chemical cross-linking approach to map the Saccharomyces cerevisiae Oxa1-ribosome interface, and we demonstrate here a close association of Oxa1 and the large ribosomal subunit protein, MrpL40. Evidence to indicate that a close physical and functional relationship exists between MrpL40 and another large ribosomal protein, the Mrp20/L23 protein, is also provided. MrpL40 shares sequence features with the bacterial ribosomal protein L24, which like Mrp20/L23 is known to be located adjacent to the ribosomal polypeptide exit site. We propose therefore that MrpL40 represents the Saccharomyces cerevisiae L24 homolog. MrpL40, like many mitochondrial ribosomal proteins, contains a C-terminal extension region that bears no similarity to the bacterial counterpart. We show that this C-terminal mitochondria-specific region is important for MrpL40's ability to support the synthesis of the correct complement of mitochondrially encoded proteins and their subsequent assembly into oxidative phosphorylation complexes.

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