The PIN domain endonuclease Utp24 cleaves pre-ribosomal RNA at two coupled sites in yeast and humans
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ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
PROVIDER: GSE75991 | GEO | 2016/04/01
SECONDARY ACCESSION(S): PRJNA305911
REPOSITORIES: GEO
Similar Datasets
Project description:Purpose: Pre-ribosomal RNA is cleaved at defined sites, but many endonucleases involved in 18S rRNA release are not known. We apply an in vivo cross-linking technique coupled with deep sequencing (CRAC) that captures transcriptome-wide interactions between a yeast candidate pre-rRNA endonuclease (Utp24) and its targets in a living cell. Methods: We apply CRAC to an HTP-tagged Utp24 protein (HTP: His6 - TEV cleavage site - two copies of the z-domain of Protein A). At least two independent experiments were performed and analyzed separately. Results: We found that yeast Utp24 UV-crosslinked in vivo to the U3 snoRNA and all (pre-)rRNA elements that form the central pseudoknot in the 18S rRNA. The pseudoknot is an evolutionarily highly conserved structure that is required to ensure pre-rRNA processing at three cleavage sites (A0, A1 and A2) and still present in the mature rRNA. According to our crosslinking data, the endonuclease Utp24 is placed in close proximity to site A1 at the 5'-end of the 18S rRNA. Conclusion: Our study strongly supports the hypothesis that Utp24 cleaves pre-rRNA at sites A1 and A2. Examination of targets for pre-rRNA endonucleases in yeast cells.
2016-04-01 | E-GEOD-75991 | biostudies-arrayexpress
Project description:Purpose: Pre-ribosomal RNA is cleaved at defined sites to release the mature ribosomal RNAs, but the functions of many ribosome biogenesis factors involved in 18S rRNA release are not known. We apply an in vivo cross-linking technique coupled with deep sequencing (CRAC) that captures transcriptome-wide interactions between the yeast PIN domain protein Utp23 and its targets in a living cell. Methods: We apply CRAC to an HTP-tagged Utp23 protein (HTP: His6 - TEV cleavage site - two copies of the z-domain of Protein A) in budding yeast. At least two independent experiments were performed and analysed separately. A non-tagged yeast strain was also used as a negative control. Results: We found that yeast Utp23 UV-crosslinked in vivo to the snR30 snoRNA and to the eukaryotic-specific expansion segment 6 (ES6) in the 18S rRNA. Conclusion: According to our crosslinking data, Utp23 is perfectly positioned to coordinate release of the snR30 snoRNA from the 18S ES6 region.
2017-01-11 | GSE87238 | GEO
Project description:Purpose: The exosome plays major roles in RNA processing and surveillance but the in vivo target range and substrate acquisition mechanisms remain unclear. We applied an in vivo cross-linking technique coupled with deep sequencing (CRAC) that captures transcriptome-wide interactions between individual yeast exosome subunits and their targets in a living cell. Methods: We apply CRAC to HTP-tagged proteins (HTP: His6 - TEV cleavage site - two copies of the z-domain of Protein A): Two nucleases (Rrp44, Rrp6) and two structural subunits (Rrp41, Csl4) of the yeast exosome. At least two independent experiments were performed in each case and analyzed separately. We performed CRAC on wild-type (WT) Rrp44 and two catalytic mutants, rrp44-endo (D91N, E120Q, D171N, D198N) and rrp44-exo (D551N). We further developed CRAC using cleavable proteins (split-CRAC) to compare endonuclease and exonuclease targets of Rrp44. Plasmids designed for split-CRAC contain a PreScission protease cleavage site (PP) inserted between aa 241 and 242 in the RRP44 ORF to allow in vitro cleavage of purified protein, and a His6 tag to select the respective cleaved fragment. Results: Analysis of wild-type Rrp44 and catalytic mutants showed that both the CUT and SUT classes of noncoding RNA, snoRNAs and, most prominently, pre-tRNAs and other Pol III transcripts are targeted for oligoadenylation and exosome degradation. Unspliced pre-mRNAs were also identified as targets for Rrp44 and Rrp6. CRAC performed using cleavable proteins (split-CRAC) revealed that Rrp44 endonuclease and exonuclease activities cooperate on most substrates. Mapping oligoadenylated reads suggests that the endonuclease activity may release stalled exosome substrates. Rrp6 was preferentially associated with structured targets, which frequently did not associate with the core exosome. This indicates that substrates can follow multiple pathways to the nucleases. Conclusion: Our study represents the first transcriptome-wide map of substrates for the yeast exosome nuclease complex. Identification of targets for individual exosome subunits in wild-type and mutant yeast cells.
2012-09-25 | E-GEOD-40046 | biostudies-arrayexpress
Project description:Purpose: The exosome plays major roles in RNA processing and surveillance but the in vivo target range and substrate acquisition mechanisms remain unclear. We applied an in vivo cross-linking technique coupled with deep sequencing (CRAC) that captures transcriptome-wide interactions between individual yeast exosome subunits and their targets in a living cell. Methods: We apply CRAC to HTP-tagged proteins (HTP: His6 - TEV cleavage site - two copies of the z-domain of Protein A): Two nucleases (Rrp44, Rrp6) and two structural subunits (Rrp41, Csl4) of the yeast exosome. At least two independent experiments were performed in each case and analyzed separately. We performed CRAC on wild-type (WT) Rrp44 and two catalytic mutants, rrp44-endo (D91N, E120Q, D171N, D198N) and rrp44-exo (D551N). We further developed CRAC using cleavable proteins (split-CRAC) to compare endonuclease and exonuclease targets of Rrp44. Plasmids designed for split-CRAC contain a PreScission protease cleavage site (PP) inserted between aa 241 and 242 in the RRP44 ORF to allow in vitro cleavage of purified protein, and a His6 tag to select the respective cleaved fragment. Results: Analysis of wild-type Rrp44 and catalytic mutants showed that both the CUT and SUT classes of noncoding RNA, snoRNAs and, most prominently, pre-tRNAs and other Pol III transcripts are targeted for oligoadenylation and exosome degradation. Unspliced pre-mRNAs were also identified as targets for Rrp44 and Rrp6. CRAC performed using cleavable proteins (split-CRAC) revealed that Rrp44 endonuclease and exonuclease activities cooperate on most substrates. Mapping oligoadenylated reads suggests that the endonuclease activity may release stalled exosome substrates. Rrp6 was preferentially associated with structured targets, which frequently did not associate with the core exosome. This indicates that substrates can follow multiple pathways to the nucleases. Conclusion: Our study represents the first transcriptome-wide map of substrates for the yeast exosome nuclease complex.
2012-09-25 | GSE40046 | GEO
Project description:The CRAC UV crosslinking technique identified numerous pre-rRNA binding sites for the large, highly conserved ribosome synthesis factor Rrp5. Intramolecular complementation has shown that the C-terminal domain (CTD) of Rrp5 is required for pre-rRNA cleavage at sites A0-A2 on the pathway of 18S rRNA synthesis, whereas the N-terminal domain (NTD) is required for A3 cleavage on the pathway of 5.8S/25S rRNA synthesis. The CTD was crosslinked to sequences flanking A2 and to the snoRNAs U3, U14, snR30 and snR10, which are required for cleavage at A0-A2. The NTD was crosslinked to the sequence flanking A3 and to the RNA component of RNase MRP, which cleaves site A3. Rrp5 could also be directly crosslinked to several large structural protein factors and NTPases. A key role in coordinating pre-ribosomal assembly and processing was confirmed by "Miller" chromatin spreads. Following depletion of Rrp5, cotranscriptional cleavage was lost and pre-ribosome compaction greatly reduced.
2013-10-14 | GSE47680 | GEO
Project description:In eukaryotes, biogenesis of ribosomes requires folding and assembly of the precursor rRNA (pre-rRNA) with a large number of proteins and snoRNPs into huge RNA-protein complexes. In spite of intense genetic, biochemical and high resolution cryo-EM studies in Saccharomyces cerevisiae, information about the conformation of the earliest 35S pre-rRNA is limited. To overcome this, we performed high-throughput SHAPE chemical probing on the 35S pre-rRNA associated with 90S pre-ribosomes. We focused our analyses on external (5´ETS) and internal (ITS1) transcribed spacers as well as the 18S region. We show that in the 35S pre-rRNA, the central region of the 18S is in a more open configuration compared to 20S pre-rRNA and that the central pseudoknot is not formed. The essential ribosome biogenesis protein Mrd1 influences the structure of the 18S part locally and is involved in organizing the central pseudoknot and surrounding structures. Our results demonstrate that the U3 snoRNA dynamically interacts with the 35S pre-rRNA and that Mrd1 is required for disrupting U3 snoRNA base-pairing interactions in the 5'ETS. We propose that the dynamic U3 snoRNA interactions and Mrd1 are essential for establishing the structure of the central region of 18S that is required for processing and 40S subunit function.
2018-01-15 | GSE106868 | GEO
Project description:Box C/D snoRNAs snR4 and snR45, whose role was unknown, guide 18S rRNA acetylations by Kre33 in yeast. UV-crosslinking (CRAC) was used to determine binding sites of Kre33 on RNA.
2017-07-25 | GSE87480 | GEO
Project description:The 18S rRNA sequence is highly conserved, particularly at its 3’-end, which is formed by the endonuclease Nob1. How Nob1 identifies its target sequence is not known, and in vitro experiments have shown Nob1 to be error-prone. Moreover, the sequence around the 3’-end is degenerate with similar sites nearby. Here we used yeast genetics, biochemistry, and next generation sequencing to investigate a role for the ATPase Rio1 in monitoring the accuracy of the 18S rRNA 3’-end. We demonstrate that Nob1 can miscleave its rRNA substrate and that miscleaved rRNA accumulates upon bypassing the Rio1-mediated quality control step, but not in healthy cells with intact quality control mechanisms. Mechanistically, we show that Rio1 binding to miscleaved rRNA is weaker than its binding to accurately processed 18S rRNA. Accordingly, excess Rio1 results in accumulation of miscleaved rRNA. Ribosomes containing miscleaved rRNA can translate, albeit more slowly, thereby inviting collisions with trailing ribosomes. These collisions result in degradation of the defective ribosomes utilizing parts of the machinery for mRNA quality control. Altogether, the data support a model in which Rio1 inspects the 3’-end of the nascent 18S rRNA to prevent miscleaved 18S rRNA-containing ribosomes from erroneously engaging in translation, where they induce ribosome collisions. The data also demonstrate how ribosome collisions purify cells of altered ribosomes with different functionalities, with important implications for the concept of ribosome heterogeneity.
2024-03-03 | GSE259239 | GEO
Project description:Ribosome biogenesis is essential for protein synthesis in gene expression. Yeast eIF5B has been shown biochemically to facilitate 18S rRNA 3’ end maturation during late-40S ribosomal subunit assembly and gate the transition from translation initiation to elongation. But the effects of eIF5B have not been studied at the genome-wide level in any organism, and 18S rRNA 3’ end maturation is poorly understood in plants. Arabidopsis HOT3/eIF5B1 was found to promote development and heat-stress acclimation by translational regulation, but its molecular function remained unknown. Here, we show that HOT3 is a late-stage ribosome biogenesis factor that facilitates 18S rRNA 3’ end processing and is a translation initiation factor that globally impacts the transition from initiation to elongation. By developing and implementing 18S-ENDseq, we revealed previously unknown events in 18S rRNA 3’ end maturation or metabolism. We quantitatively defined new processing hotspots and identified adenylation as the prevalent non-templated RNA modification at the 3’ ends of pre-18S rRNAs. Aberrant 18S rRNA maturation in hot3 further activated RNAi to generate RDR1- and DCL2/4-dependent risiRNAs mainly from a 3’ portion of 18S rRNA. We further showed that risiRNAs in hot3 were predominantly localized in ribosome-free fractions not responsible for the 18S rRNA maturation or translation initiation defects in hot3. Our study uncovered the molecular function of HOT3/eIF5B1 in 18S rRNA maturation at the late-40S assembly stage and revealed the regulatory crosstalk among ribosome biogenesis, mRNA translation initiation, and siRNA biogenesis in plants.
2023-04-19 | GSE223171 | GEO
Project description:Ribosome biogenesis is essential for protein synthesis in gene expression. Yeast eIF5B has been shown biochemically to facilitate 18S rRNA 3’ end maturation during late-40S ribosomal subunit assembly and gate the transition from translation initiation to elongation. But the effects of eIF5B have not been studied at the genome-wide level in any organism, and 18S rRNA 3’ end maturation is poorly understood in plants. Arabidopsis HOT3/eIF5B1 was found to promote development and heat-stress acclimation by translational regulation, but its molecular function remained unknown. Here, we show that HOT3 is a late-stage ribosome biogenesis factor that facilitates 18S rRNA 3’ end processing and is a translation initiation factor that globally impacts the transition from initiation to elongation. By developing and implementing 18S-ENDseq, we revealed previously unknown events in 18S rRNA 3’ end maturation or metabolism. We quantitatively defined new processing hotspots and identified adenylation as the prevalent non-templated RNA modification at the 3’ ends of pre-18S rRNAs. Aberrant 18S rRNA maturation in hot3 further activated RNAi to generate RDR1- and DCL2/4-dependent risiRNAs mainly from a 3’ portion of 18S rRNA. We further showed that risiRNAs in hot3 were predominantly localized in ribosome-free fractions not responsible for the 18S rRNA maturation or translation initiation defects in hot3. Our study uncovered the molecular function of HOT3/eIF5B1 in 18S rRNA maturation at the late-40S assembly stage and revealed the regulatory crosstalk among ribosome biogenesis, mRNA translation initiation, and siRNA biogenesis in plants.
2023-04-19 | GSE223169 | GEO