S17 Protein Research Articles

Analysis of the meiotic role of the mitochondrial ribosomal proteins Mrps17 and Mrpl37 in Saccharomyces cerevisiae

Sporulation in the yeast Saccharomyces cerevisiae is a complex and tightly regulated pathway that involves the induction of a large number of genes. We have identified MRPS17 in a cDNA library enriched for sporulation-specific genes. Homology searches show that the first one-third of Mrps17 has strong sequence similarity to bacterial S17 proteins, suggesting that Mrps17 is a potential mitochondrial ribosomal protein. This is further supported by the fact that mrps17Delta cells are respiratory-deficient and that a Mrps17-GFP fusion localizes to the mitochondria. We have confirmed by Northern blot analysis that both MRPS17 and MRPL37 are strongly induced during the middle stages of sporulation and that this induction is dependent on the presence of a middle sporulation element (MSE) in the promoters of these genes. Interestingly, we found that Mrps17 and Mrpl37, but not other mitochondrial ribosomal proteins, accumulate during the middle stages of sporulation. These results suggest that Mrps17 and Mrpl37 may have additional meiosis-specific roles.

Nucleotide sequence of the gene for ribosomal protein S17 from Dictyostelium discoideum

The nucleotide sequence of the gene for the Dictyostelium homologue of eukaryotic ribosomal protein S17 has been assembled from cDNA and genomic DNA clones. The predicted primary structure of the S17 protein displays a similar level of sequence identity with its counterparts from higher eukaryotes (53%) as other Dictyostelium ribosomal proteins. Although Dictyostelium genes usually are organized in a rather simple manner, the rps17 gene harbors two introns. One of them, located immediately 3′ from the ATG initiator codon, appears to be ubiquitously conserved in eukaryotic rps17 genes.

The Drosophila melanogaster RPS17 gene encoding ribosomal protein S17

A human ribosomal protein S 17 cDNA [Chen et al., Proc. Natl. Acad.β Sci. USA 83 (1986) 6907–6911] was used as heterologous probe to isolate S17 clones from Drosophila genomic and cDNA recombinant libraries. Five S17 genomic clones were recognized; all contained overlapping regions of a single chromosomal site. Subsequently the Drosophila RPS17 gene was mapped by in situ hybridization to chromosome 3L, band 67B 1–5. The locus spans approximately 1000 bp of DNA and includes four exons. It is preceded by conventional CAAT and TATA RNA polymerase II promoter motifs. The 131 amino acid protein encoded within Drosophila RPS 17 is similar to ribosomal proteins from several other eukaryotes. Comparison of eukaryotic S17 proteins' primary structures as well as the number and location of their genes' intervening sequences suggest that S 17 is a relatively recent addition to the ribosomal protein family, probably post-dating divergence of eukaryotes and prokaryotes.

Low temperature growth of AIN and Al 2O 3 films by the simultaneous use of a microwave ion source and an ionized cluster beam system Hiroshi Takaoka et al,Thin Solid Films,157, 1988, 143–158

A human ribosomal protein S 17 cDNA [Chen et al., Proc. Natl. Acad.β Sci. USA 83 (1986) 6907–6911] was used as heterologous probe to isolate S17 clones from Drosophila genomic and cDNA recombinant libraries. Five S17 genomic clones were recognized; all contained overlapping regions of a single chromosomal site. Subsequently the Drosophila RPS17 gene was mapped by in situ hybridization to chromosome 3L, band 67B 1–5. The locus spans approximately 1000 bp of DNA and includes four exons. It is preceded by conventional CAAT and TATA RNA polymerase II promoter motifs. The 131 amino acid protein encoded within Drosophila RPS 17 is similar to ribosomal proteins from several other eukaryotes. Comparison of eukaryotic S17 proteins' primary structures as well as the number and location of their genes' intervening sequences suggest that S 17 is a relatively recent addition to the ribosomal protein family, probably post-dating divergence of eukaryotes and prokaryotes.

Molecular cloning and nucleotide sequences of cDNAs specific for rat liver ribosomal proteins S17 and L30

cDNA clones coding for rat liver ribosomal proteins S17 and L30 have been isolated by positive hybridization-translation assay from a cDNA library prepared from 8-9S poly(A) + RNA from free polysomes of regenerating rat liver. The cDNA clone specific for S 17 protein (pRS 17-2) has a 466-bp insert with the poly(A) tail. The complete amino acid(aa) sequence of S 17 protein was deduced from the nucleotide sequence of the cDNA. S17 protein consists of 134 aa residues with an M r of 15377. The N-terminal aa sequence of S17 protein determined by automatic Edman degradation is consistent with the sequence data. The aa sequence of S17 shows strong homology (76.9%) to that of yeast ribosomal protein 51 [Teem and Rosbash, Proc. Natl. Acad. Sci. USA 80 (1983) 4403-4407] in the two-thirds N-terminal region. The cDNA clone specific for L30 protein (pRL30) has a 394-bp insert. The aa sequence of L30 protein was deduced from the nucleotide sequence of the cDNA. The protein consists of 114 aa residues with an M r of 12652. When compared with the N-terminal aa sequence of rat liver L30 protein [Wool, Annu. Rev. Biochem. 48 (1979) 719-754], pRL30 was found not to contain the initiation codon and 5'-noncoding region. The cDNA showed twelve silent changes in the coding region, one point mutation and one base deletion in the 3 ' -noncoding region, compared with mouse genomic DNA for L30 protein [Wiedemann and Perry, Mol. Cell Biol. 4 (1984) 2518-2528].

Altered ribosomal proteins in emetine resistant strains in the fungus Podospora anserina

Emetine resistant mutants have been isolated in the fungus Podospora anserina. Genetic analysis of 75 mutants has shown that resistance is controlled by at least two genes, EmR1 and EmR2. In vitro studies showed that resistance to emetine in EmR1 and EMR2 mutants was due to alterations in the protein synthesis machinery. Reconstitution experiments with ribosomal subunits prepared from wild-type and resistant strains indicated that emetine resistance is associated with the 40S subunit.The strains resistant to emetine are also hypersensitive to anisomycin in vivo. In poly-U directed polyphenylalanine synthesis or run off of polysomes, it was shown that mutant ribosomes do not differ from those of wild-type with regard to anisomycin sensitivity, pointing out that initiation would be lso an anisomycin target. The ribosomal proteins isolated from resistant mutants were analyzed by two dimensional gel electrophoresis and compared with the proteins of wild-type ribosomes. The EmR40 mutant was found to have an altered S14 protein. In EmR69, three proteins of the small subunit S13, S15 and S17 were altered, nevertheless only altered S13 and S17 proteins segregate with the resistance character. The comparison of proteolytic digestion of S13 and S17 on SDS gel allowed us to conclude that S13 and S17 would be homologous proteins.

Alteration of ribosomal protein S17 by mutation linked to neamine resistance in Escherichia coli: II. Localization of the amino acid replacement in protein S17 from a neaA mutant

A mutant of Escherichia coli strain K12S, nea R301, resistant to the antibiotic neamine was found to have an altered 30 S ribosomal protein S17. The modification involves a change in the electrophoretic mobility of this protein. S17 proteins wore purified from the mutant and the parental strain, respectively, and the amino acid compositions of all tryptic peptides were compared. The results show that the mutational alteration involves a replacement of histidine by proline in peptide T8 from mutant nea R301. The amino acid replacement is located at position 30 of the S17 protein chain. We conclude, therefore, that the mutation nea R301 affects the structural gene for protein S17 ( rps Q).

Alteration of ribosomal protein S17 by mutation linked to neamine resistance in Escherichia coli: I. General properties of neaA mutants

A mutant of Escherichia coli strain K12S isolated after selection for resistance to the amino glycoside antibiotic neamine shows severe restriction of amber suppressors in vivo . Ribosomes from the mutant exhibit low neamine-induced misreading in vitro and a decreased affinity for the related antibiotic streptomycin. The S17 ribosomal protein from the mutant strain shows altered electrophoretic mobility on two-dimensional polyacrylamide gels and also differs in chromatographical behaviour from the S17 protein from the parental strain. When ribosomes from the mutant strain are reconstituted in the presence of a molar excess of the S17 protein from the wild type species, the particles exhibit normal druginduced misreading properties as well as a normal capacity for binding streptomycin. The gene involved in the alteration of protein S17 ( rpxQ ) is located inside the ribosomal protein gene cluster at 64 minutes on the E. coli genetic map and cotransduces at 96% with rpxE (S5).