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Demirci H Murphy F Belardinelli R Kelley AC Ramakrishnan V Gregory ST Dahlberg AE Jogl G 《RNA (New York, N.Y.)》2010,16(12):2319-2324
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Vemanna S. Ramu Akashata Dawane Seonghee Lee Sunhee Oh Hee-Kyung Lee Liang Sun Muthappa Senthil-Kumar Kirankumar S. Mysore 《Molecular Plant Pathology》2020,21(11):1481-1494
Ribosomes play an integral part in plant growth, development, and defence responses. We report here the role of ribosomal protein large (RPL) subunit QM/RPL10 in nonhost disease resistance. The RPL10-silenced Nicotiana benthamiana plants showed compromised disease resistance against nonhost pathogen Pseudomonas syringae pv. tomato T1. The RNA-sequencing analysis revealed that many genes involved in defence and protein translation mechanisms were differentially affected due to silencing of NbRPL10. Arabidopsis AtRPL10 RNAi and rpl10 mutant lines showed compromised nonhost disease resistance to P. syringae pv. tomato T1 and P. syringae pv. tabaci. Overexpression of AtRPL10A in Arabidopsis resulted in reduced susceptibility against host pathogen P. syringae pv. tomato DC3000. RPL10 interacts with the RNA recognition motif protein and ribosomal proteins RPL30, RPL23, and RPS30 in the yeast two-hybrid assay. Silencing or mutants of genes encoding these RPL10-interacting proteins in N. benthamiana or Arabidopsis, respectively, also showed compromised disease resistance to nonhost pathogens. These results suggest that QM/RPL10 positively regulates the defence and translation-associated genes during nonhost pathogen infection. 相似文献
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Hong‐Yue Guo Zeng‐Qiang Gao Heng Zhang Yong Wei Jian‐Hua Xu Wen‐Ya Wang Ai‐xia Yan Yu‐Hui Dong 《Acta Crystallographica. Section F, Structural Biology Communications》2013,69(6):640-642
RlmM is an AdoMet‐dependent methyltransferase that is responsible for 2′‐O‐methylation of C2498 in the peptidyl‐transferase loop of bacterial 23S rRNA. This modification occurs before assembly of the 50S ribosomal subunit, and lack of C2498 methylation can cause a slight reduction in bacterial fitness. Here, the purification and crystallization of RlmM from Escherichia coli as well as its preliminary crystallographic analysis are presented. Cocrystallization of RlmM with AdoMet was carried out and X‐ray diffraction data were collected to a resolution of 2.30 Å on beamline BL17U at the SSRF. However, electron density for AdoMet cannot be observed by comprehensive crystallographic analysis, indicating that it is not bound by RlmM during the cocrystallization process. The structure was solved by molecular replacement and refinement is in progress. The crystal contained one molecule in the asymmetric unit and belonged to space group P21, with unit‐cell parameters a = 56.07, b = 59.38, c = 54.35 Å, β = 94.84°, which differs from the P31 or P3121 space groups of previously reported RlmM structures (PDB entries 4auk , 4atn and 4b17 ). 相似文献
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Eukaryotic cells have quality control systems that eliminate nonfunctional rRNAs with deleterious mutations (nonfunctional rRNA decay, NRD). We have previously reported that 25S NRD requires an E3 ubiquitin ligase complex, which is involved in ribosomal ubiquitination. However, the degradation process of nonfunctional ribosomes has remained unknown. Here, using genetic screening, we identified two ubiquitin-binding complexes, the Cdc48-Npl4-Ufd1 complex (Cdc48 complex) and the proteasome, as the factors involved in 25S NRD. We show that the nonfunctional 60S subunit is dissociated from the 40S subunit in a Cdc48 complex-dependent manner, before it is attacked by the proteasome. When we examined the nonfunctional 60S subunits that accumulated under proteasome-depleted conditions, the majority of mutant 25S rRNAs retained their full length at a single-nucleotide resolution. This indicates that the proteasome is an essential factor triggering rRNA degradation. We further showed that ribosomal ubiquitination can be stimulated solely by the suppression of the proteasome, suggesting that ubiquitin-proteasome-dependent RNA degradation occurs in broader situations, including in general rRNA turnover. 相似文献
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Yasuhiko Suzuki Tatsuo Mori Yasuko Miyata Takeshi Yamada 《FEMS microbiology letters》1987,44(1):73-76
Southern hybridization of Mycobacterium lepraemurium DNA with 16S, 23S, 5S rRNA from Mycobacterium bovis BCG was carried out. It was concluded that M. lepraemurium may possess a minimum set of rRNA genes and tRNA genes were linked to genes for 5S and 23S rRNA genes. 相似文献
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Zhang DY Ampasala DR Zheng SC Cusson M Cheng XW Krell PJ Feng QL 《Archives of insect biochemistry and physiology》2006,61(4):209-219
RNA helicases play important roles in cellular processes such as pre-mRNA splicing, rRNA processing, ribosomal biogenesis, and translation. A full-length DEAD box RNA helicase cDNA (CfrHlc113) was isolated from the spruce budworm, Choristoneura fumiferana. CfrHlc113 contained the eight functional motifs, which are highly conserved in the DEAD box RNA helicase family, and an arginine-serine-aspartate (RSD) domain at its N-terminal end. CfrHlc113 was highly homologous to Rattus norvegicus HEL117 and human prp5 genes, both of which are suggested to be involved in RNA splicing. The results of Northern and Western blotting showed that expression of the CfrHlc113 gene was low or undetectable in eggs, larvae, pupae, and adults. High levels of expression were, however, detected in the three in vitro cultured cell lines, CF-203, CF-124T, and CF-70, which were developed from the midgut, ovaries, and neonate larvae, respectively. Immunocytochemistry revealed that CfrHlc113 protein was present exclusively in the nuclei of these cell lines. 相似文献
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《Molecular cell》2020,77(6):1222-1236.e13
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Quantitative analysis of snoRNA association with pre-ribosomes and release of snR30 by Rok1 helicase
In yeast, three small nucleolar RNAs (snoRNAs) are essential for the processing of pre-ribosomal RNA—U3, U14 and snR30—whereas 72 non-essential snoRNAs direct site-specific modification of pre-rRNA. We applied a quantitative screen for alterations in the pre-ribosome association to all 75 yeast snoRNAs in strains depleted of eight putative helicases implicated in 40S subunit synthesis. For the modification-guide snoRNAs, we found no clear evidence for the involvement of these helicases in the association or dissociation of pre-ribosomes. However, the DEAD box helicase Rok1 was required specifically for the release of snR30. Point mutations in motif I, but not in motif III, of the helicase domain of Rok1 impaired the release of snR30, but this was less marked than in strains depleted of Rok1, and resulted in a dominant-negative growth phenotype. Dissociation of U3 and U14 from pre-ribosomes is also dependent on helicases, suggesting that release of the essential snoRNAs might differ mechanistically from release of the modification-guide snoRNAs. 相似文献
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利用基因组数据和生物信息学分析方法,快速鉴定耐药基因并预测耐药表型,为细菌耐药状况监测提供了有力辅助手段。目前,已有的数十个耐药数据库及其相关分析工具这些资源为细菌耐药基因的识别以及耐药表型的预测提供了数据信息和技术手段。随着细菌基因组数据的持续增加以及耐药表型数据的不断积累,大数据和机器学习能够更好地建立耐药表型与基因组信息之间的相关性,因此,构建高效的耐药表型预测模型成为研究热点。本文围绕细菌耐药基因的识别和耐药表型的预测,针对耐药相关数据库、耐药特征识别理论与方法、耐药数据的机器学习与表型预测等方面展开讨论,以期为细菌耐药的相关研究提供手段和思路。 相似文献
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Ribosomes are large ribozymes that synthesize all cellular proteins. As protein synthesis is rate-limiting for bacterial growth and ribosomes can comprise a large portion of the cellular mass, elucidation of ribosomal turnover is important to the understanding of cellular physiology. Although ribosomes are widely believed to be stable in growing cells, this has never been rigorously tested, owing to the lack of a suitable experimental system in commonly used bacterial model organisms. Here, we develop an experimental system to directly measure ribosomal stability in Escherichia coli. We show that (i) ribosomes are stable when cells are grown at a constant rate in the exponential phase; (ii) more than half of the ribosomes made during exponential growth are degraded during slowing of culture growth preceding the entry into stationary phase; and (iii) ribosomes are stable for many hours in the stationary phase. Ribosome degradation occurs in growing cultures that contain almost no dead cells and coincides with a reduction of comparable magnitude in the cellular RNA concentration. 相似文献
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Mohammad-Taher Moradi Hossein Fallahi Zohreh Rahimi 《Journal of cellular biochemistry》2019,120(3):3339-3352
The competitive endogenous RNA (ceRNA) hypothesis suggests that a long noncoding RNA (lncRNA) can function as sinks for pools of microRNAs (miRNAs); thereby, in the presence of ceRNA, messenger RNAs (mRNAs) targeted by specific miRNAs can liberate and translate to protein. Maternally expressed gene 3 (MEG3) is a lncRNA, which its expression has been detected in various normal tissues, while it is lost or downregulated in human tumors. The MEG3 is an imprinted gene which, is methylated and suppressed by DNA methyltransferases (DNMTs) family. Also, miRNAs are involved in the regulation of MEG3 gene expression. Interestingly, the lncRNA MEG3 (lnc-MEG3), as a ceRNA affects various cell processes such as proliferation, apoptosis, and angiogenesis by sponging miRNAs. These miRNAs, in turn, regulate different mRNAs in different pathways. This review focuses on the interaction between lnc-MEG3 and experimentally validated miRNAs. In addition, the discussion supplemented by some data obtained from mirPath (v.3) and TarBase (v.8) databanks to provide more details about the pathways affected by this ceRNA. 相似文献
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Translation of polyphenylalanine from a polyuridine template by the ribosome in the absence of the elongation factors EFG and EFTu (and the energy derived from GTP hydrolysis) is promoted by modification of the ribosome with thiol-specific reagents such as para-chloromercuribenzoate (pCMB). Here, we examine the translational cycle of modified ribosomes and show that peptide bond formation and tRNA binding are largely unaffected, whereas translocation of the mRNA:tRNA complex is substantially promoted by pCMB modification. The translocation movements that we observe are authentic by multiple criteria including the processivity of translation, accuracy of movement (three-nucleotide) along a defined mRNA template and sensitivity to antibiotics. Characterization of the modified ribosomes reveals that the protein content of the ribosomes is not depleted but that their subunit association properties are severely compromised. These data suggest that molecular targets (ribosomal proteins) in the interface region of the ribosome are critical barriers that influence the translocation of the mRNA:tRNA complex. 相似文献
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Rya Ero Veerendra Kumar Weixin Su Yong‐Gui Gao 《Protein science : a publication of the Protein Society》2019,28(4):684-693
Members of the ATP‐binding cassette F (ABC‐F) proteins confer resistance to several classes of clinically important antibiotics through ribosome protection. Recent structures of two ABC‐F proteins, Pseudomonas aeruginosa MsrE and Bacillus subtilis VmlR bound to ribosome have shed light onto the ribosome protection mechanism whereby drug resistance is mediated by the antibiotic resistance domain (ARD) connecting the two ATP binding domains. ARD of the E site bound MsrE and VmlR extends toward the drug binding region within the peptidyl transferase center (PTC) and leads to conformational changes in the P site tRNA acceptor stem, the PTC, and the drug binding site causing the release of corresponding drugs. The structural similarities and differences of the MsrE and VmlR structures likely highlight an universal ribosome protection mechanism employed by antibiotic resistance (ARE) ABC‐F proteins. The variable ARD domains enable this family of proteins to adapt the protection mechanism for several classes of ribosome‐targeting drugs. ARE ABC‐F genes have been found in numerous pathogen genomes and multi‐drug resistance conferring plasmids. Collectively they mediate resistance to a broader range of antimicrobial agents than any other group of resistance proteins and play a major role in clinically significant drug resistance in pathogenic bacteria. Here, we review the recent structural and biochemical findings on these emerging resistance proteins, offering an update of the molecular basis and implications for overcoming ABC‐F conferred drug resistance. 相似文献