scholarly journals A Novel Drosophila Minute Locus Encodes Ribosomal Protein S13

Genetics ◽  
1996 ◽  
Vol 143 (2) ◽  
pp. 877-885 ◽  
Author(s):  
Stein Saeboe-Larssen ◽  
Andrew Lambertsson

Abstract Minutes comprise >50 phenotypically similar Drosophila mutations believed to affect ribosomal protein genes. Common traits of the Minute phenotype are short and thin bristles, slow development, and recessive lethality. To further investigate the proposed Minute to ribosomal protein correspondence, loss-of-function Minute mutations were induced by P-element mutagenesis. Here, we report a previously undescribed Minute locus that maps to 32A on chromosome 2L; this Minute allele is named P{lac-W}M(2)32A1 and the gene M(2)32A. Flies heterozygous for P{lacW}M(2)32A1 have a medium Minute phenotype. The gene interrupted by the P-element insertion was cloned. Sequence analyses revealed that it encodes the Drosophila homologue of eukaryotic ribosomal protein S13. It is a singlecopy gene and the level of RPS13 transcript is reduced to ~50% in P{lacW}M(2)32A1 heterozygotes. Both transcript level and phenotype are restored to wild type by remobilizing the P element, demonstrating that the mutation is caused by insertion of the P-element construct. These results further strengthen the notion that Minutes encode ribosomal proteins and demonstrate that P-element mutagenesis is a fruitful approach to use in these studies.

1983 ◽  
Vol 3 (3) ◽  
pp. 457-465
Author(s):  
C H Kim ◽  
J R Warner

In Saccharomyces cerevisiae the synthesis of ribosomal proteins declines temporarily after a culture has been subjected to a mild temperature shock, i.e., a shift from 23 to 36 degrees C, each of which support growth. Using cloned genes for several S. cerevisiae ribosomal proteins, we found that the changes in the synthesis of ribosomal proteins parallel the changes in the concentration of mRNA of each. The disappearance and reappearance of the mRNA is due to a brief but severe inhibition of the transcription of each of the ribosomal protein genes, although the total transcription of mRNA in the cells is relatively unaffected by the temperature shock. The precisely coordinated response of these genes, which are scattered throughout the genome, suggests that either they or the enzyme which transcribes them has unique properties. In certain S. cerevisiae mutants, the synthesis of ribosomal proteins never recovers from a temperature shift. Yet both the decline and the resumption of transcription of these genes during the 30 min after the temperature shift are indistinguishable from those in wild-type cells. The failure of the mutant cells to grow at the restrictive temperature appears to be due to their inability to process the RNA transcribed from genes which have introns (Rosbash et al., Cell 24:679-686, 1981), a large proportion of which appear to be ribosomal protein genes.


Genetics ◽  
1992 ◽  
Vol 132 (2) ◽  
pp. 375-386 ◽  
Author(s):  
A Vincent ◽  
S W Liebman

Abstract The accurate synthesis of proteins is crucial to the existence of a cell. In yeast, several genes that affect the fidelity of translation have been identified (e.g., omnipotent suppressors, antisuppressors and allosuppressors). We have found that the dominant omnipotent suppressor SUP46 encodes the yeast ribosomal protein S13. S13 is encoded by two similar genes, but only the sup46 copy of the gene is able to fully complement the recessive phenotypes of SUP46 mutations. Both copies of the S13 genes contain introns. Unlike the introns of other duplicated ribosomal protein genes which are highly diverged, the duplicated S13 genes have two nearly identical DNA sequences of 25 and 31 bp in length within their introns. The SUP46 protein has significant homology to the S4 ribosomal protein in prokaryotic-type ribosomes. S4 is encoded by one of the ram (ribosomal ambiguity) genes in Escherichia coli which are the functional equivalent of omnipotent suppressors in yeast. Thus, SUP46 and S4 demonstrate functional as well as sequence conservation between prokaryotic and eukaryotic ribosomal proteins. SUP46 and S4 are most similar in their central amino acid sequences. Interestingly, the alterations resulting from the SUP46 mutations and the segment of the S4 protein involved in binding to the 16S rRNA are within this most conserved region.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Edmund Ui-Hang Sim ◽  
Stella Li-Li Chan ◽  
Kher-Lee Ng ◽  
Choon-Weng Lee ◽  
Kumaran Narayanan

Apart from their canonical role in ribosome biogenesis, there is increasing evidence of ribosomal protein genes’ involvement in various cancers. A previous study by us revealed significant differential expression of three ribosomal protein genes (RPeL27, RPeL41, and RPeL43) between cell lines derived from tumor and normal nasopharyngeal epithelium. However, the results therein were based on a semiquantitative assay, thus preliminary in nature. Herein, we provide findings of a deeper analysis of these three genes in the context to nasopharyngeal carcinoma (NPC) tumorigenesis. Their expression patterns were analyzed in a more quantitative manner at transcript level. Their protein expression levels were also investigated. We showed results that are contrary to previous report. Rather than downregulation, these genes were significantly overexpressed in NPC cell lines compared to normal control at both transcript and protein levels. Nevertheless, their association with NPC has been established. Immunoprecipitation pulldown assays indicate the plausible interaction of either RPeL27 or RPeL43 with POTEE/TUBA1A and ACTB/ACTBL2 complexes. In addition, RPeL43 is shown to bind with MRAS and EIF2S1 proteins in a NPC cell line (HK1). Our findings support RPeL27, RPeL41, and RPeL43 as potential markers of NPC and provide insights into the interaction targets of RPeL27 and RPeL43 proteins.


1985 ◽  
Vol 5 (1) ◽  
pp. 99-108
Author(s):  
H M Fried ◽  
H G Nam ◽  
S Loechel ◽  
J Teem

We placed a regulatory sequence derived from the GAL10 locus of Saccharomyces cerevisiae at various distances from the start sites of transcription of two yeast ribosomal protein genes, tcm1 and cyh2. The hybrid ribosomal protein genes were transcribed at wild-type levels in the presence of galactose. In the absence of galactose, the hybrid genes were transcribed either at a reduced level or essentially not at all. Yeast cells which transcribe the ribosomal protein genes at a reduced rate continued to grow, suggesting that enhanced translation of the ribosomal protein mRNA may permit an adequate rate of synthesis of the corresponding protein. Consistent with this suggestion is the finding that preexisting mRNA decayed at a reduced rate when transcription was halted abruptly by removal of galactose. Yeast cells unable to transcribe tcm1 or cyh2 without galactose did not grow. These conditional lethal strains demonstrate that the ribosomal proteins encoded by tcm1 and cyh2 are essential; furthermore, these strains are potentially useful for isolating mutations in the tcm1 and cyh2 proteins affecting their transport, assembly, or function.


1985 ◽  
Vol 5 (1) ◽  
pp. 99-108 ◽  
Author(s):  
H M Fried ◽  
H G Nam ◽  
S Loechel ◽  
J Teem

We placed a regulatory sequence derived from the GAL10 locus of Saccharomyces cerevisiae at various distances from the start sites of transcription of two yeast ribosomal protein genes, tcm1 and cyh2. The hybrid ribosomal protein genes were transcribed at wild-type levels in the presence of galactose. In the absence of galactose, the hybrid genes were transcribed either at a reduced level or essentially not at all. Yeast cells which transcribe the ribosomal protein genes at a reduced rate continued to grow, suggesting that enhanced translation of the ribosomal protein mRNA may permit an adequate rate of synthesis of the corresponding protein. Consistent with this suggestion is the finding that preexisting mRNA decayed at a reduced rate when transcription was halted abruptly by removal of galactose. Yeast cells unable to transcribe tcm1 or cyh2 without galactose did not grow. These conditional lethal strains demonstrate that the ribosomal proteins encoded by tcm1 and cyh2 are essential; furthermore, these strains are potentially useful for isolating mutations in the tcm1 and cyh2 proteins affecting their transport, assembly, or function.


1983 ◽  
Vol 3 (3) ◽  
pp. 457-465 ◽  
Author(s):  
C H Kim ◽  
J R Warner

In Saccharomyces cerevisiae the synthesis of ribosomal proteins declines temporarily after a culture has been subjected to a mild temperature shock, i.e., a shift from 23 to 36 degrees C, each of which support growth. Using cloned genes for several S. cerevisiae ribosomal proteins, we found that the changes in the synthesis of ribosomal proteins parallel the changes in the concentration of mRNA of each. The disappearance and reappearance of the mRNA is due to a brief but severe inhibition of the transcription of each of the ribosomal protein genes, although the total transcription of mRNA in the cells is relatively unaffected by the temperature shock. The precisely coordinated response of these genes, which are scattered throughout the genome, suggests that either they or the enzyme which transcribes them has unique properties. In certain S. cerevisiae mutants, the synthesis of ribosomal proteins never recovers from a temperature shift. Yet both the decline and the resumption of transcription of these genes during the 30 min after the temperature shift are indistinguishable from those in wild-type cells. The failure of the mutant cells to grow at the restrictive temperature appears to be due to their inability to process the RNA transcribed from genes which have introns (Rosbash et al., Cell 24:679-686, 1981), a large proportion of which appear to be ribosomal protein genes.


2013 ◽  
Vol 12 (3) ◽  
pp. 450-459 ◽  
Author(s):  
Rongpeng Li ◽  
Xuesong Li ◽  
Lei Sun ◽  
Feifei Chen ◽  
Zhenxing Liu ◽  
...  

ABSTRACTDeletion of ribosomal protein L32 genes resulted in a nonsexual flocculation of fission yeast. Nonsexual flocculation also occurred when two other ribosomal protein genes,rpl21-2andrpl9-2, were deleted. However, deletion of two nonribosomal protein genes,mpgandfbp, did not cause flocculation. Overall transcript levels ofrpl32inrpl32-1Δ andrpl32-2Δ cells were reduced by 35.9% and 46.9%, respectively, and overall ribosome levels inrpl32-1Δ andrpl32-2Δ cells dropped 31.1% and 27.8%, respectively, compared to wild-type cells. Interestingly, ribosome protein expression levels and ribosome levels were also reduced greatly in sexually flocculating diploid YHL6381/WT (h+/h−) cells compared to a mixture of YHL6381 (h+) and WT (h−) nonflocculating haploid cells. Transcriptome analysis indicated that the reduction of ribosomal levels in sexual flocculating cells was caused by more-extensive suppression of ribosomal biosynthesis gene expression, while the reduction of ribosomal levels caused by deleting ribosomal protein genes in nonsexual flocculating cells was due to an imbalance between ribosomal proteins. We propose that once the reduction of ribosomal levels is below a certain threshold value, flocculation is triggered.


1990 ◽  
Vol 10 (10) ◽  
pp. 5235-5243 ◽  
Author(s):  
D M Baronas-Lowell ◽  
J R Warner

In the yeast Saccharomyces cerevisiae, L30 is one of many ribosomal proteins that is encoded by two functional genes. We have cloned and sequenced RPL30B, which shows strong homology to RPL30A. Use of mRNA as a template for a polymerase chain reaction demonstrated that RPL30B contains an intron in its 5' untranslated region. This intron has an unusual 5' splice site, C/GUAUGU. The genomic copies of RPL30A and RPL30B were disrupted by homologous recombination. Growth rates, primer extension, and two-dimensional ribosomal protein analyses of these disruption mutants suggested that RPL30A is responsible for the majority of L30 production. Surprisingly, meiosis of a diploid strain carrying one disrupted RPL30A and one disrupted RPL30B yielded four viable spores. Ribosomes from haploid cells carrying both disrupted genes had no detectable L30, yet such cells grew with a doubling time only 30% longer than that of wild-type cells. Furthermore, depletion of L30 did not alter the ratio of 60S to 40S ribosomal subunits, suggesting that there is no serious effect on the assembly of 60S subunits. Polysome profiles, however, suggest that the absence of L30 leads to the formation of stalled translation initiation complexes.


1990 ◽  
Vol 10 (10) ◽  
pp. 5235-5243
Author(s):  
D M Baronas-Lowell ◽  
J R Warner

In the yeast Saccharomyces cerevisiae, L30 is one of many ribosomal proteins that is encoded by two functional genes. We have cloned and sequenced RPL30B, which shows strong homology to RPL30A. Use of mRNA as a template for a polymerase chain reaction demonstrated that RPL30B contains an intron in its 5' untranslated region. This intron has an unusual 5' splice site, C/GUAUGU. The genomic copies of RPL30A and RPL30B were disrupted by homologous recombination. Growth rates, primer extension, and two-dimensional ribosomal protein analyses of these disruption mutants suggested that RPL30A is responsible for the majority of L30 production. Surprisingly, meiosis of a diploid strain carrying one disrupted RPL30A and one disrupted RPL30B yielded four viable spores. Ribosomes from haploid cells carrying both disrupted genes had no detectable L30, yet such cells grew with a doubling time only 30% longer than that of wild-type cells. Furthermore, depletion of L30 did not alter the ratio of 60S to 40S ribosomal subunits, suggesting that there is no serious effect on the assembly of 60S subunits. Polysome profiles, however, suggest that the absence of L30 leads to the formation of stalled translation initiation complexes.


Cancers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 582 ◽  
Author(s):  
Jung ◽  
Lee ◽  
Kim ◽  
Sim ◽  
Ahn ◽  
...  

Among ribosomal proteins essential for protein synthesis, the functions of ribosomal protein L5 (RPL5) and RPL11 still remain unclear to date. Here, the roles of RPL5 and RPL11 were investigated in association with p53/p21 signaling in the antitumor effect of puromycin mainly in HCT116 and H1299 cancer cells. Cell proliferation assays using 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assays and colony formation assays, cell cycle analysis, Reverse transcription polymerase chain reaction (RT-PCR) and Western blotting were performed in cancer cells. Puromycin exerted cytotoxic and anti-proliferative effects in p53 wild-type HCT116 more than in p53 null H1299 cells. Consistently, puromycin increased sub-G1, cleaved Poly (ADP-ribose) polymerase (PARP), activated p53, p21, and Mouse double minute 2 homolog (MDM2), and attenuated expression of c-Myc in HCT116 cells. Notably, puromycin upregulated the expression of RPL5 and RPL11 to directly bind to MDM2 in HCT116 cells. Conversely, deletion of RPL5 and RPL11 blocked the activation of p53, p21, and MDM2 in HCT116 cells. Also, puromycin enhanced the antitumor effect with reactivating p53 and inducing tumor apoptosis (RITA) or doxorubicin in HCT116 cells. These findings suggest that puromycin induces p53-dependent apoptosis via upregulation of RPL5 or RPL11 for binding with MDM2, and so can be used more effectively in p53 wild-type cancers by combination with RITA or doxorubicin.


Sign in / Sign up

Export Citation Format

Share Document