Search tips
Search criteria 


Logo of molcellbPermissionsJournals.ASM.orgJournalMCB ArticleJournal InfoAuthorsReviewers
Mol Cell Biol. 1993 December; 13(12): 7935–7941.
PMCID: PMC364865

Nuclear RNase MRP is required for correct processing of pre-5.8S rRNA in Saccharomyces cerevisiae.


RNase MRP is a site-specific ribonucleoprotein endoribonuclease that cleaves RNA from the mitochondrial origin of replication in a manner consistent with a role in priming leading-strand DNA synthesis. Despite the fact that the only known RNA substrate for this enzyme is complementary to mitochondrial DNA, the majority of the RNase MRP activity in a cell is found in the nucleus. The recent characterization of this activity in Saccharomyces cerevisiae and subsequent cloning of the gene coding for the RNA subunit of the yeast enzyme have enabled a genetic approach to the identification of a nuclear role for this ribonuclease. Since the gene for the RNA component of RNase MRP, NME1, is essential in yeast cells and RNase MRP in mammalian cells appears to be localized to nucleoli within the nucleus, we utilized both regulated expression and temperature-conditional mutations of NME1 to assay for a possible effect on rRNA processing. Depletion of the RNA component of the enzyme was accomplished by using the glucose-repressed GAL1 promoter. Shortly after the shift to glucose, the RNA component of the enzyme was found to be depleted severely, and rRNA processing was found to be normal at all sites except the B1 processing site. The B1 site, at the 5' end of the mature 5.8S rRNA, is actually composed of two cleavage sites 7 nucleotides apart. This cleavage normally generates two species of 5.8S rRNA at a ratio of 10:1 (small to large) in most eukaryotes. After RNase MRP depletion, yeast cells were found to have almost exclusively the larger species of 5.8S rRNA. In addition, an aberrant 309-nucleotide precursor that stretched from the A2 to E processing sites of rRNA accumulated in these cells. Temperature-conditional mutations in the RNase MRP RNA gene gave an identical phenotype.Translation in yeast cells depleted of the smaller 5.8S rRNA was found to remain robust, suggesting a possible function for two 5.8S rRNAs in the regulated translation of select messages. These results are consistent with RNase MRP playing a role in a late step of rRNA processing. The data also indicate a requirement for having the smaller form of 5.8S rRNA, and they argue for processing at the B1 position being composed of two separate cleavage events catalyzed by two different activities.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1.4M), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Amberg DC, Goldstein AL, Cole CN. Isolation and characterization of RAT1: an essential gene of Saccharomyces cerevisiae required for the efficient nucleocytoplasmic trafficking of mRNA. Genes Dev. 1992 Jul;6(7):1173–1189. [PubMed]
  • Bowman LH, Goldman WE, Goldberg GI, Hebert MB, Schlessinger D. Location of the initial cleavage sites in mouse pre-rRNA. Mol Cell Biol. 1983 Aug;3(8):1501–1510. [PMC free article] [PubMed]
  • Chang DD, Clayton DA. A novel endoribonuclease cleaves at a priming site of mouse mitochondrial DNA replication. EMBO J. 1987 Feb;6(2):409–417. [PubMed]
  • Chang DD, Clayton DA. A mammalian mitochondrial RNA processing activity contains nucleus-encoded RNA. Science. 1987 Mar 6;235(4793):1178–1184. [PubMed]
  • Chang DD, Clayton DA. Mouse RNAase MRP RNA is encoded by a nuclear gene and contains a decamer sequence complementary to a conserved region of mitochondrial RNA substrate. Cell. 1989 Jan 13;56(1):131–139. [PubMed]
  • Forster AC, Altman S. Similar cage-shaped structures for the RNA components of all ribonuclease P and ribonuclease MRP enzymes. Cell. 1990 Aug 10;62(3):407–409. [PubMed]
  • Fournier MJ, Maxwell ES. The nucleolar snRNAs: catching up with the spliceosomal snRNAs. Trends Biochem Sci. 1993 Apr;18(4):131–135. [PubMed]
  • Gold HA, Topper JN, Clayton DA, Craft J. The RNA processing enzyme RNase MRP is identical to the Th RNP and related to RNase P. Science. 1989 Sep 22;245(4924):1377–1380. [PubMed]
  • Hughes JM, Konings DA, Cesareni G. The yeast homologue of U3 snRNA. EMBO J. 1987 Jul;6(7):2145–2155. [PubMed]
  • Karwan R, Bennett JL, Clayton DA. Nuclear RNase MRP processes RNA at multiple discrete sites: interaction with an upstream G box is required for subsequent downstream cleavages. Genes Dev. 1991 Jul;5(7):1264–1276. [PubMed]
  • Lindahl L, Archer RH, Zengel JM. A new rRNA processing mutant of Saccharomyces cerevisiae. Nucleic Acids Res. 1992 Jan 25;20(2):295–301. [PMC free article] [PubMed]
  • Patterson B, Guthrie C. An essential yeast snRNA with a U5-like domain is required for splicing in vivo. Cell. 1987 Jun 5;49(5):613–624. [PubMed]
  • Reimer G, Raska I, Scheer U, Tan EM. Immunolocalization of 7-2-ribonucleoprotein in the granular component of the nucleolus. Exp Cell Res. 1988 May;176(1):117–128. [PubMed]
  • Rubin GM. Three forms of the 5.8-S ribosomal RNA species in Saccharomyces cerevisiae. Eur J Biochem. 1974 Jan 3;41(1):197–202. [PubMed]
  • Schimmang T, Tollervey D, Kern H, Frank R, Hurt EC. A yeast nucleolar protein related to mammalian fibrillarin is associated with small nucleolar RNA and is essential for viability. EMBO J. 1989 Dec 20;8(13):4015–4024. [PubMed]
  • Schmitt ME, Bennett JL, Dairaghi DJ, Clayton DA. Secondary structure of RNase MRP RNA as predicted by phylogenetic comparison. FASEB J. 1993 Jan;7(1):208–213. [PubMed]
  • Schmitt ME, Brown TA, Trumpower BL. A rapid and simple method for preparation of RNA from Saccharomyces cerevisiae. Nucleic Acids Res. 1990 May 25;18(10):3091–3092. [PMC free article] [PubMed]
  • Schmitt ME, Clayton DA. Yeast site-specific ribonucleoprotein endoribonuclease MRP contains an RNA component homologous to mammalian RNase MRP RNA and essential for cell viability. Genes Dev. 1992 Oct;6(10):1975–1985. [PubMed]
  • Seraphin B, Rosbash M. Identification of functional U1 snRNA-pre-mRNA complexes committed to spliceosome assembly and splicing. Cell. 1989 Oct 20;59(2):349–358. [PubMed]
  • Sherman F. Getting started with yeast. Methods Enzymol. 1991;194:3–21. [PubMed]
  • Shuai K, Warner JR. A temperature sensitive mutant of Saccharomyces cerevisiae defective in pre-rRNA processing. Nucleic Acids Res. 1991 Sep 25;19(18):5059–5064. [PMC free article] [PubMed]
  • Sikorski RS, Hieter P. A system of shuttle vectors and yeast host strains designed for efficient manipulation of DNA in Saccharomyces cerevisiae. Genetics. 1989 May;122(1):19–27. [PubMed]
  • Smith SD, Banerjee N, Sitz TO. Gene heterogeneity: a basis for alternative 5.8S rRNA processing. Biochemistry. 1984 Jul 31;23(16):3648–3652. [PubMed]
  • Stohl LL, Clayton DA. Saccharomyces cerevisiae contains an RNase MRP that cleaves at a conserved mitochondrial RNA sequence implicated in replication priming. Mol Cell Biol. 1992 Jun;12(6):2561–2569. [PMC free article] [PubMed]
  • Tollervey D. A yeast small nuclear RNA is required for normal processing of pre-ribosomal RNA. EMBO J. 1987 Dec 20;6(13):4169–4175. [PubMed]
  • Topper JN, Bennett JL, Clayton DA. A role for RNAase MRP in mitochondrial RNA processing. Cell. 1992 Jul 10;70(1):16–20. [PubMed]
  • Topper JN, Clayton DA. Characterization of human MRP/Th RNA and its nuclear gene: full length MRP/Th RNA is an active endoribonuclease when assembled as an RNP. Nucleic Acids Res. 1990 Feb 25;18(4):793–799. [PMC free article] [PubMed]
  • Warner JR. Synthesis of ribosomes in Saccharomyces cerevisiae. Microbiol Rev. 1989 Jun;53(2):256–271. [PMC free article] [PubMed]
  • Warner JR. Labeling of RNA and phosphoproteins in Saccharomyces cerevisiae. Methods Enzymol. 1991;194:423–428. [PubMed]
  • Woolford JL., Jr The structure and biogenesis of yeast ribosomes. Adv Genet. 1991;29:63–118. [PubMed]

Articles from Molecular and Cellular Biology are provided here courtesy of American Society for Microbiology (ASM)