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Zhang W, Zhang M, Ma L, Jariyasakulroj S, Chang Q, Lin Z, Lu Z, Chen JF. Recapitulating and reversing human brain ribosomopathy defects via the maladaptive integrated stress response. SCIENCE ADVANCES 2024; 10:eadk1034. [PMID: 38306425 PMCID: PMC10836730 DOI: 10.1126/sciadv.adk1034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 01/03/2024] [Indexed: 02/04/2024]
Abstract
Animal or human models recapitulating brain ribosomopathies are incomplete, hampering development of urgently needed therapies. Here, we generated genetic mouse and human cerebral organoid models of brain ribosomopathies, caused by mutations in small nucleolar RNA (snoRNA) SNORD118. Both models exhibited protein synthesis loss, proteotoxic stress, and p53 activation and led to decreased proliferation and increased death of neural progenitor cells (NPCs), resulting in brain growth retardation, recapitulating features in human patients. Loss of SNORD118 function resulted in an aberrant upregulation of p-eIF2α, the mediator of integrated stress response (ISR). Using human iPSC cell-based screen, we identified small-molecule 2BAct, an ISR inhibitor, which potently reverses mutant NPC defects. Targeting ISR by 2BAct mitigated ribosomopathy defects in both cerebral organoid and mouse models. Thus, our SNORD118 mutant organoid and mice recapitulate human brain ribosomopathies and cross-validate maladaptive ISR as a key disease-driving mechanism, pointing to a therapeutic intervention strategy.
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Affiliation(s)
- Wei Zhang
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Minjie Zhang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Li Ma
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Supawadee Jariyasakulroj
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Qing Chang
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Ziying Lin
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Zhipeng Lu
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Jian-Fu Chen
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
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2
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Jariyasakulroj S, Zhang W, Bai J, Zhang M, Lu Z, Chen JF. Ribosome biogenesis controls cranial suture MSC fate via the complement pathway in mouse and human iPSC models. Stem Cell Reports 2023; 18:2370-2385. [PMID: 37977145 PMCID: PMC10724072 DOI: 10.1016/j.stemcr.2023.10.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 10/22/2023] [Accepted: 10/23/2023] [Indexed: 11/19/2023] Open
Abstract
Disruption of global ribosome biogenesis selectively affects craniofacial tissues with unclear mechanisms. Craniosynostosis is a congenital craniofacial disorder characterized by premature fusion of cranial suture(s) with loss of suture mesenchymal stem cells (MSCs). Here we focused on ribosomopathy disease gene Snord118, which encodes a small nucleolar RNA (snoRNA), to genetically disturb ribosome biogenesis in suture MSCs using mouse and human induced pluripotent stem cell (iPSC) models. Snord118 depletion exhibited p53 activation, increased cell death, reduced proliferation, and premature osteogenic differentiation of MSCs, leading to suture growth and craniosynostosis defects. Mechanistically, Snord118 deficiency causes translational dysregulation of ribosomal proteins and downregulation of complement pathway genes. Further complement pathway disruption by knockout of complement C3a receptor 1 (C3ar1) exacerbated MSC and suture defects in mutant mice, whereas activating the complement pathway rescued MSC cell fate and suture growth defects. Thus, ribosome biogenesis controls MSC fate via the complement pathway to prevent craniosynostosis.
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Affiliation(s)
- Supawadee Jariyasakulroj
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA; Department of Masticatory Science, Faculty of Dentistry, Mahidol University, Bangkok 10400, Thailand
| | - Wei Zhang
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA
| | - Jianhui Bai
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Minjie Zhang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Zhipeng Lu
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Jian-Fu Chen
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA 90033, USA.
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3
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Politano D, Catalano G, Pezzotti E, Varesio C, Sirchia F, Casella A, Rognone E, Pichiecchio A, Borgatti R, Orcesi S. Expanding the Natural History of SNORD118-Related Ribosomopathy: Hints from an Early-Diagnosed Patient with Leukoencephalopathy with Calcifications and Cysts and Overview of the Literature. Genes (Basel) 2023; 14:1817. [PMID: 37761957 PMCID: PMC10531261 DOI: 10.3390/genes14091817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Revised: 09/11/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Leukoencephalopathy with calcifications and cysts (LCC) is a rare autosomal recessive disorder showing a pediatric or adult onset. First described in 1996 by Labrune and colleagues, it was only in 2016 that bi-allelic variants in a non-protein coding gene, SNORD118, were found as the cause for LCC, differentiating this syndrome from coats plus (CP). SNORD118 transcribes for a small nucleolar RNA, which is necessary for correct ribosome biogenesis, hence the classification of LCC among ribosomopathies. The syndrome is characterized by a combination of white matter hyperintensities, calcifications, and cysts on brain MRI with varying neurological signs. Corticosteroids, surgery, and recently bevacizumab, have been tried with unclear results since the natural history of the disease remains elusive. To date, 67 patients with a pediatric onset of disease have been described in the literature, with a clinical-radiological follow-up carried out in only eleven of them. We described the clinical-radiological follow-up from birth to almost five years of age of a late-preterm patient diagnosed with LCC and carried out a thorough overview of pediatric patients described in the literature. It is important to gather serial clinical-radiological data from other patients to depict the natural history of this disease, aiming to deeply depict genotype-phenotype correlations and make the role of new therapeutics clearer.
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Affiliation(s)
- Davide Politano
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Guido Catalano
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Elena Pezzotti
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- U.O. Neuropsichiatria Infanzia e Adolescenza, ASST Bergamo Est, 24068 Seriate, Italy
| | - Costanza Varesio
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Fabio Sirchia
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Medical Genetics Unit, IRCCS San Matteo Foundation, 27100 Pavia, Italy
| | - Antonella Casella
- Department of Molecular Medicine, University of Pavia, 27100 Pavia, Italy
- Neurogenetics Research Center, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Elisa Rognone
- Neuroradiology Department, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Anna Pichiecchio
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- Neuroradiology Department, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Renato Borgatti
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Simona Orcesi
- Department of Brain and Behavior Neuroscience, University of Pavia, 27100 Pavia, Italy
- Child Neurology and Psychiatry Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy
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4
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McCool MA, Bryant CJ, Huang H, Ogawa LM, Farley-Barnes KI, Sondalle SB, Abriola L, Surovtseva YV, Baserga SJ. Human nucleolar protein 7 (NOL7) is required for early pre-rRNA accumulation and pre-18S rRNA processing. RNA Biol 2023; 20:257-271. [PMID: 37246770 PMCID: PMC10228412 DOI: 10.1080/15476286.2023.2217392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2023] [Indexed: 05/30/2023] Open
Abstract
The main components of the essential cellular process of eukaryotic ribosome biogenesis are highly conserved from yeast to humans. Among these, the U3 Associated Proteins (UTPs) are a small subunit processome subcomplex that coordinate the first two steps of ribosome biogenesis in transcription and pre-18S processing. While we have identified the human counterparts of most of the yeast Utps, the homologs of yeast Utp9 and Bud21 (Utp16) have remained elusive. In this study, we find that NOL7 is the likely ortholog of Bud21. Previously described as a tumour suppressor through regulation of antiangiogenic transcripts, we now show that NOL7 is required for early pre-rRNA accumulation and pre-18S rRNA processing in human cells. These roles lead to decreased protein synthesis and induction of the nucleolar stress response upon NOL7 depletion. Beyond Bud21's nonessential role in yeast, we establish human NOL7 as an essential UTP that is necessary to maintain both early pre-rRNA levels and processing.
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Affiliation(s)
- Mason A. McCool
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Carson J. Bryant
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Hannah Huang
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Lisa M. Ogawa
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Katherine I. Farley-Barnes
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA
| | - Samuel B. Sondalle
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Laura Abriola
- Yale Center for Molecular Discovery, Yale University, West Haven, CT, USA
| | | | - Susan J. Baserga
- Department of Molecular Biophysics & Biochemistry, Yale University School of Medicine, New Haven, CT, USA
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
- Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT, USA
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5
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Liao H, Gaur A, McConie H, Shekar A, Wang K, Chang JT, Breton G, Denicourt C. Human NOP2/NSUN1 regulates ribosome biogenesis through non-catalytic complex formation with box C/D snoRNPs. Nucleic Acids Res 2022; 50:10695-10716. [PMID: 36161484 PMCID: PMC9561284 DOI: 10.1093/nar/gkac817] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 09/14/2022] [Indexed: 11/18/2022] Open
Abstract
5-Methylcytosine (m5C) is a base modification broadly found on various RNAs in the human transcriptome. In eukaryotes, m5C is catalyzed by enzymes of the NSUN family composed of seven human members (NSUN1-7). NOP2/NSUN1 has been primarily characterized in budding yeast as an essential ribosome biogenesis factor required for the deposition of m5C on the 25S ribosomal RNA (rRNA). Although human NOP2/NSUN1 has been known to be an oncogene overexpressed in several types of cancer, its functions and substrates remain poorly characterized. Here, we used a miCLIP-seq approach to identify human NOP2/NSUN1 RNA substrates. Our analysis revealed that NOP2/NSUN1 catalyzes the deposition of m5C at position 4447 on the 28S rRNA. We also find that NOP2/NSUN1 binds to the 5′ETS region of the pre-rRNA transcript and regulates pre-rRNA processing through non-catalytic complex formation with box C/D snoRNAs. We provide evidence that NOP2/NSUN1 facilitates the recruitment of U3 and U8 snoRNAs to pre-90S ribosomal particles and their stable assembly into snoRNP complexes. Remarkably, expression of both WT and catalytically inactive NOP2/NSUN1 in knockdown background rescues the rRNA processing defects and the stable assembly of box C/D snoRNP complexes, suggesting that NOP2/NSUN1-mediated deposition of m5C on rRNA is not required for ribosome synthesis.
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Affiliation(s)
- Han Liao
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Anushri Gaur
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Hunter McConie
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Amirtha Shekar
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Karen Wang
- Wiess College, Rice University, Houston, TX 77251, USA
| | - Jeffrey T Chang
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Ghislain Breton
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
| | - Catherine Denicourt
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center, Houston, TX 77030, USA
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6
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McFadden EJ, Baserga SJ. U8 variants on the brain: a small nucleolar RNA and human disease. RNA Biol 2022; 19:412-418. [PMID: 35389826 PMCID: PMC8993069 DOI: 10.1080/15476286.2022.2048563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Small nucleolar RNAs (snoRNAs) are non-coding RNAs vital for ribosomal RNA (rRNA) maturation. The U8 snoRNA, encoded by the SNORD118 gene in humans, is an atypical C/D box snoRNA as it promotes rRNA cleavage rather than 2′–O–methylation and is unique to vertebrates. The U8 snoRNA is critical for cleavage events that produce the mature 5.8S and 28S rRNAs of the large ribosomal subunit. Unexpectedly, single nucleotide polymorphisms (SNPs) in the SNORD118 gene were recently found causal to the neurodegenerative disease leukoencephalopathy, brain calcifications, and cysts (LCC; aka Labrune syndrome), but its molecular pathogenesis is unclear. Here, we will review current knowledge on the function of the U8 snoRNA in ribosome biogenesis, and connect it to the preservation of brain function in humans as well as to its dysregulation in inherited white matter disease.
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Affiliation(s)
- Emily J McFadden
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Susan J Baserga
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Department of Genetics, Yale School of Medicine, New Haven, CT, USA.,Department of Therapeutic Radiology, Yale School of Medicine, New Haven, CT, USA
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7
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Han C, Sun LY, Luo XQ, Pan Q, Sun YM, Zeng ZC, Chen TQ, Huang W, Fang K, Wang WT, Chen YQ. Chromatin-associated orphan snoRNA regulates DNA damage-mediated differentiation via a non-canonical complex. Cell Rep 2022; 38:110421. [PMID: 35354054 DOI: 10.1016/j.celrep.2022.110421] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 10/04/2021] [Accepted: 01/31/2022] [Indexed: 12/21/2022] Open
Abstract
Small nucleolar RNAs (snoRNAs) are commonly acknowledged as a class of homogeneous non-coding RNAs that guide ribosomal RNA modifications. However, snoRNAs referred to as orphans have largely unknown functions. Here, we systematically profile chromatin-associated snoRNAs (casnoRNAs) in mammalian cells and identify a subgroup of orphan casnoRNAs responding to DNA damage stress, among which SNORA73 shows the most marked reduction in chromatin enrichment. Downregulated SNORA73 maintains cancer genome stability and differentiation block in hematopoietic malignancy. Mechanistically, casnoRNA the 5' end non-canonical structure of SNORA73 is critical for its function and binding to poly (ADP-ribose) polymerase 1 (PARP1). SNORA73 inhibits PARP1 auto-PARylation to affect cancer genome stability by forming a small nucleolar ribonucleoprotein (snoRNP) with PARP1 and canonical H/ACA proteins DKC1/NHP2. Our findings reveal the role of an orphan snoRNA serving as casnoRNA and highlights a link between non-canonical structure of snoRNA and their functional diversity.
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Affiliation(s)
- Cai Han
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Lin-Yu Sun
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Xue-Qun Luo
- The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510080, China
| | - Qi Pan
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Yu-Meng Sun
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Zhan-Cheng Zeng
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Tian-Qi Chen
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Wei Huang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Ke Fang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China
| | - Wen-Tao Wang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China.
| | - Yue-Qin Chen
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, Guangdong 510275, China.
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8
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Abstract
Eukaryotic ribosome biogenesis involves the synthesis of ribosomal RNA (rRNA) and its stepwise folding into the unique structure present in mature ribosomes. rRNA folding starts already co-transcriptionally in the nucleolus and continues when pre-ribosomal particles further maturate in the nucleolus and upon their transit to the nucleoplasm and cytoplasm. While the approximate order of folding of rRNA subdomains is known, especially from cryo-EM structures of pre-ribosomal particles, the actual mechanisms of rRNA folding are less well understood. Both small nucleolar RNAs (snoRNAs) and proteins have been implicated in rRNA folding. snoRNAs hybridize to precursor rRNAs (pre-rRNAs) and thereby prevent premature folding of the respective rRNA elements. Ribosomal proteins (r-proteins) and ribosome assembly factors might have a similar function by binding to rRNA elements and preventing their premature folding. Besides that, a small group of ribosome assembly factors are thought to play a more active role in rRNA folding. In particular, multiple RNA helicases participate in individual ribosome assembly steps, where they are believed to coordinate RNA folding/unfolding events or the release of proteins from the rRNA. In this review, we summarize the current knowledge on mechanisms of RNA folding and on the specific function of the individual RNA helicases involved. As the yeast Saccharomyces cerevisiae is the organism in which ribosome biogenesis and the role of RNA helicases in this process is best studied, we focused our review on insights from this model organism, but also make comparisons to other organisms where applicable.
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Affiliation(s)
- Valentin Mitterer
- Biochemistry Center, Heidelberg University, Im Neuenheimer Feld 328, Heidelberg, Germany.,BioTechMed-Graz, Graz, Austria
| | - Brigitte Pertschy
- BioTechMed-Graz, Graz, Austria.,Institute of Molecular Biosciences, University of Graz, Humboldtstrasse 50, Graz, Austria
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9
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Aquino GRR, Hackert P, Krogh N, Pan KT, Jaafar M, Henras AK, Nielsen H, Urlaub H, Bohnsack KE, Bohnsack MT. The RNA helicase Dbp7 promotes domain V/VI compaction and stabilization of inter-domain interactions during early 60S assembly. Nat Commun 2021; 12:6152. [PMID: 34686661 PMCID: PMC8536713 DOI: 10.1038/s41467-021-26208-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 09/22/2021] [Indexed: 02/07/2023] Open
Abstract
Early pre-60S ribosomal particles are poorly characterized, highly dynamic complexes that undergo extensive rRNA folding and compaction concomitant with assembly of ribosomal proteins and exchange of assembly factors. Pre-60S particles contain numerous RNA helicases, which are likely regulators of accurate and efficient formation of appropriate rRNA structures. Here we reveal binding of the RNA helicase Dbp7 to domain V/VI of early pre-60S particles in yeast and show that in the absence of this protein, dissociation of the Npa1 scaffolding complex, release of the snR190 folding chaperone, recruitment of the A3 cluster factors and binding of the ribosomal protein uL3 are impaired. uL3 is critical for formation of the peptidyltransferase center (PTC) and is responsible for stabilizing interactions between the 5′ and 3′ ends of the 25S, an essential pre-requisite for subsequent pre-60S maturation events. Highlighting the importance of pre-ribosome remodeling by Dbp7, our data suggest that in the absence of Dbp7 or its catalytic activity, early pre-ribosomal particles are targeted for degradation. Early steps of large 60S ribosomal subunit biogenesis are not well understood. Here, the authors combine biochemical experiments with protein-RNA crosslinking and mass spectrometry to show that the RNA helicase Dbp7 is key player during early 60S ribosomal assembly. Dbp7 regulates a series of events driving compaction of domain V/VI in early pre60S ribosomal particles.
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Affiliation(s)
- Gerald Ryan R Aquino
- Department of Molecular Biology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Philipp Hackert
- Department of Molecular Biology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany
| | - Nicolai Krogh
- Department of Cellular and Molecular Medicine, University of Copenhagen, 2200N, Copenhagen, Denmark
| | - Kuan-Ting Pan
- Max Planck Institute for Biophysical Chemistry, Bioanalytical Mass Spectrometry, 37077, Göttingen, Germany.,Hematology/Oncology, Department of Medicine II, Johann Wolfgang Goethe University, 60590, Frankfurt am Main, Germany.,Frankfurt Cancer Institute, Goethe University, 60596, Frankfurt am Main, Germany
| | - Mariam Jaafar
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062, Toulouse, France
| | - Anthony K Henras
- Molecular, Cellular and Developmental Biology Unit (MCD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062, Toulouse, France
| | - Henrik Nielsen
- Department of Cellular and Molecular Medicine, University of Copenhagen, 2200N, Copenhagen, Denmark.,Genomics Group, Faculty of Biosciences and Aquaculture, Nord University, 8049, Bodø, Norway
| | - Henning Urlaub
- Max Planck Institute for Biophysical Chemistry, Bioanalytical Mass Spectrometry, 37077, Göttingen, Germany.,Institute for Clinical Chemistry, University Medical Center Göttingen, 37075, Göttingen, Germany
| | - Katherine E Bohnsack
- Department of Molecular Biology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany.
| | - Markus T Bohnsack
- Department of Molecular Biology, University Medical Center Göttingen, Humboldtallee 23, 37073, Göttingen, Germany. .,Göttingen Centre for Molecular Biosciences, Georg-August-University, Justus-von-Liebig Weg 11, 37077, Göttingen, Germany.
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10
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Commuting to Work: Nucleolar Long Non-Coding RNA Control Ribosome Biogenesis from Near and Far. Noncoding RNA 2021; 7:ncrna7030042. [PMID: 34287370 PMCID: PMC8293466 DOI: 10.3390/ncrna7030042] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 07/09/2021] [Accepted: 07/11/2021] [Indexed: 12/26/2022] Open
Abstract
Gene expression is an essential process for cellular growth, proliferation, and differentiation. The transcription of protein-coding genes and non-coding loci depends on RNA polymerases. Interestingly, numerous loci encode long non-coding (lnc)RNA transcripts that are transcribed by RNA polymerase II (RNAPII) and fine-tune the RNA metabolism. The nucleolus is a prime example of how different lncRNA species concomitantly regulate gene expression by facilitating the production and processing of ribosomal (r)RNA for ribosome biogenesis. Here, we summarise the current findings on how RNAPII influences nucleolar structure and function. We describe how RNAPII-dependent lncRNA can both promote nucleolar integrity and inhibit ribosomal (r)RNA synthesis by modulating the availability of rRNA synthesis factors in trans. Surprisingly, some lncRNA transcripts can directly originate from nucleolar loci and function in cis. The nucleolar intergenic spacer (IGS), for example, encodes nucleolar transcripts that counteract spurious rRNA synthesis in unperturbed cells. In response to DNA damage, RNAPII-dependent lncRNA originates directly at broken ribosomal (r)DNA loci and is processed into small ncRNA, possibly to modulate DNA repair. Thus, lncRNA-mediated regulation of nucleolar biology occurs by several modes of action and is more direct than anticipated, pointing to an intimate crosstalk of RNA metabolic events.
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11
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Kovalenko TF, Larionova TD, Antipova NV, Shakhparonov MI, Pavlyukov MS. The Role of Non-coding RNAs in the Pathogenesis of Glial Tumors. Acta Naturae 2021; 13:38-51. [PMID: 34707896 PMCID: PMC8526181 DOI: 10.32607/actanaturae.11270] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 03/15/2021] [Indexed: 11/25/2022] Open
Abstract
Among the many malignant neoplasms, glioblastoma (GBM) leads to one of the worst prognosis for patients and has an almost 100% recurrence rate. The only chemotherapeutic drug that is widely used for treating glioblastoma is temozolomide, a DNA alkylating agent. Its impact, however, is only minor; it increases patients' survival just by 12 to 14 months. Multiple highly selective compounds that affect specific proteins and have performed well in other types of cancer have proved ineffective against glioblastoma. Hence, there is an urgent need for novel methods that could help achieve the long-awaited progress in glioblastoma treatment. One of the potentially promising approaches is the targeting of non-coding RNAs (ncRNAs). These molecules are characterized by extremely high multifunctionality and often act as integrators by coordinating multiple key signaling pathways within the cell. Thus, the impact on ncRNAs has the potential to lead to a broader and stronger impact on cells, as opposed to the more focused action of inhibitors targeting specific proteins. In this review, we summarize the functions of long noncoding RNAs, circular RNAs, as well as microRNAs, PIWI-interacting RNAs, small nuclear and small nucleolar RNAs. We provide a classification of these transcripts and describe their role in various signaling pathways and physiological processes. We also provide examples of oncogenic and tumor suppressor ncRNAs belonging to each of these classes in the context of their involvement in the pathogenesis of gliomas and glioblastomas. In conclusion, we considered the potential use of ncRNAs as diagnostic markers and therapeutic targets for the treatment of glioblastoma.
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Affiliation(s)
- T. F. Kovalenko
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Moscow, 117997 Russia
| | - T. D. Larionova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Moscow, 117997 Russia
| | - N. V. Antipova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Moscow, 117997 Russia
| | - M. I. Shakhparonov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Moscow, 117997 Russia
| | - M. S. Pavlyukov
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry Russian Academy of Sciences, Moscow, 117997 Russia
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12
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Zhang M, Li K, Bai J, Velema WA, Yu C, van Damme R, Lee WH, Corpuz ML, Chen JF, Lu Z. Optimized photochemistry enables efficient analysis of dynamic RNA structuromes and interactomes in genetic and infectious diseases. Nat Commun 2021; 12:2344. [PMID: 33879794 PMCID: PMC8058046 DOI: 10.1038/s41467-021-22552-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Accepted: 03/18/2021] [Indexed: 02/02/2023] Open
Abstract
Direct determination of RNA structures and interactions in living cells is critical for understanding their functions in normal physiology and disease states. Here, we present PARIS2, a dramatically improved method for RNA duplex determination in vivo with >4000-fold higher efficiency than previous methods. PARIS2 captures ribosome binding sites on mRNAs, reporting translation status on a transcriptome scale. Applying PARIS2 to the U8 snoRNA mutated in the neurological disorder LCC, we discover a network of dynamic RNA structures and interactions which are destabilized by patient mutations. We report the first whole genome structure of enterovirus D68, an RNA virus that causes polio-like symptoms, revealing highly dynamic conformations altered by antiviral drugs and different pathogenic strains. We also discover a replication-associated asymmetry on the (+) and (-) strands of the viral genome. This study establishes a powerful technology for efficient interrogation of the RNA structurome and interactome in human diseases.
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MESH Headings
- Calcinosis/genetics
- Calcinosis/metabolism
- Central Nervous System Cysts/genetics
- Central Nervous System Cysts/metabolism
- Communicable Diseases/genetics
- Communicable Diseases/metabolism
- Cross-Linking Reagents
- Enterovirus D, Human/genetics
- Furocoumarins
- Genetic Diseases, Inborn/genetics
- Genetic Diseases, Inborn/metabolism
- Genome, Viral
- Humans
- Leukoencephalopathies/genetics
- Leukoencephalopathies/metabolism
- Models, Molecular
- Mutation
- Nucleic Acid Conformation
- Photochemical Processes
- Photochemistry/methods
- RNA/chemistry
- RNA/genetics
- RNA/metabolism
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Small Nucleolar/chemistry
- RNA, Small Nucleolar/genetics
- RNA, Small Nucleolar/metabolism
- RNA, Viral/chemistry
- RNA, Viral/genetics
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Affiliation(s)
- Minjie Zhang
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Kongpan Li
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Jianhui Bai
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Willem A Velema
- Institute for Molecules and Materials, Radboud University Nijmegen, Nijmegen, The Netherlands
| | - Chengqing Yu
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Ryan van Damme
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Wilson H Lee
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Maia L Corpuz
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA
| | - Jian-Fu Chen
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, CA, USA
| | - Zhipeng Lu
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA, USA.
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13
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Liu S, Li B, Liang Q, Liu A, Qu L, Yang J. Classification and function of RNA-protein interactions. WILEY INTERDISCIPLINARY REVIEWS-RNA 2020; 11:e1601. [PMID: 32488992 DOI: 10.1002/wrna.1601] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/15/2020] [Accepted: 04/29/2020] [Indexed: 12/11/2022]
Abstract
Almost all RNAs need to interact with proteins to fully exert their functions, and proteins also bind to RNAs to act as regulators. It has now become clear that RNA-protein interactions play important roles in many biological processes among organisms. Despite the great progress that has been made in the field, there is still no precise classification system for RNA-protein interactions, which makes it challenging to further decipher the functions and mechanisms of these interactions. In this review, we propose four different categories of RNA-protein interactions according to their basic characteristics: RNA motif-dependent RNA-protein interactions, RNA structure-dependent RNA-protein interactions, RNA modification-dependent RNA-protein interactions, and RNA guide-based RNA-protein interactions. Moreover, the integration of different types of RNA-protein interactions and the regulatory factors implicated in these interactions are discussed. Furthermore, we emphasize the functional diversity of these four types of interactions in biological processes and disease development and assess emerging trends in this exciting research field. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition RNA Processing > RNA Editing and Modification.
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Affiliation(s)
- Shurong Liu
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Bin Li
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Qiaoxia Liang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Anrui Liu
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Lianghu Qu
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jianhua Yang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, School of Life Sciences, Sun Yat-sen University, Guangzhou, China.,Department of Interventional Medicine, The Fifth Affiliated Hospital, Sun Yat-sen University, Zhuhai, China
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14
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Ojha S, Malla S, Lyons SM. snoRNPs: Functions in Ribosome Biogenesis. Biomolecules 2020; 10:biom10050783. [PMID: 32443616 PMCID: PMC7277114 DOI: 10.3390/biom10050783] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/10/2020] [Accepted: 05/13/2020] [Indexed: 01/18/2023] Open
Abstract
Ribosomes are perhaps the most critical macromolecular machine as they are tasked with carrying out protein synthesis in cells. They are incredibly complex structures composed of protein components and heavily chemically modified RNAs. The task of assembling mature ribosomes from their component parts consumes a massive amount of energy and requires greater than 200 assembly factors. Among the most critical of these are small nucleolar ribonucleoproteins (snoRNPs). These are small RNAs complexed with diverse sets of proteins. As suggested by their name, they localize to the nucleolus, the site of ribosome biogenesis. There, they facilitate multiple roles in ribosomes biogenesis, such as pseudouridylation and 2′-O-methylation of ribosomal (r)RNA, guiding pre-rRNA processing, and acting as molecular chaperones. Here, we reviewed their activity in promoting the assembly of ribosomes in eukaryotes with regards to chemical modification and pre-rRNA processing.
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Affiliation(s)
- Sandeep Ojha
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02115, USA; (S.O.); (S.M.)
| | - Sulochan Malla
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02115, USA; (S.O.); (S.M.)
| | - Shawn M. Lyons
- Department of Biochemistry, Boston University School of Medicine, Boston, MA 02115, USA; (S.O.); (S.M.)
- The Genome Science Institute, Boston University School of Medicine, Boston, MA 02115, USA
- Correspondence: ; Tel.: +1-617-358-4280
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15
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Analysis of U8 snoRNA Variants in Zebrafish Reveals How Bi-allelic Variants Cause Leukoencephalopathy with Calcifications and Cysts. Am J Hum Genet 2020; 106:694-706. [PMID: 32359472 DOI: 10.1016/j.ajhg.2020.04.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/30/2020] [Indexed: 12/16/2022] Open
Abstract
How mutations in the non-coding U8 snoRNA cause the neurological disorder leukoencephalopathy with calcifications and cysts (LCC) is poorly understood. Here, we report the generation of a mutant U8 animal model for interrogating LCC-associated pathology. Mutant U8 zebrafish exhibit defective central nervous system development, a disturbance of ribosomal RNA (rRNA) biogenesis and tp53 activation, which monitors ribosome biogenesis. Further, we demonstrate that fibroblasts from individuals with LCC are defective in rRNA processing. Human precursor-U8 (pre-U8) containing a 3' extension rescued mutant U8 zebrafish, and this result indicates conserved biological function. Analysis of LCC-associated U8 mutations in zebrafish revealed that one null and one functional allele contribute to LCC. We show that mutations in three nucleotides at the 5' end of pre-U8 alter the processing of the 3' extension, and we identify a previously unknown base-pairing interaction between the 5' end and the 3' extension of human pre-U8. Indeed, LCC-associated mutations in any one of seven nucleotides in the 5' end and 3' extension alter the processing of pre-U8, and these mutations are present on a single allele in almost all individuals with LCC identified to date. Given genetic data indicating that bi-allelic null U8 alleles are likely incompatible with human development, and that LCC is not caused by haploinsufficiency, the identification of hypomorphic misprocessing mutations that mediate viable embryogenesis furthers our understanding of LCC molecular pathology and cerebral vascular homeostasis.
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16
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Bratkovič T, Božič J, Rogelj B. Functional diversity of small nucleolar RNAs. Nucleic Acids Res 2020; 48:1627-1651. [PMID: 31828325 PMCID: PMC7038934 DOI: 10.1093/nar/gkz1140] [Citation(s) in RCA: 121] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/17/2019] [Accepted: 12/05/2019] [Indexed: 12/22/2022] Open
Abstract
Small nucleolar RNAs (snoRNAs) are short non-protein-coding RNAs with a long-recognized role in tuning ribosomal and spliceosomal function by guiding ribose methylation and pseudouridylation at targeted nucleotide residues of ribosomal and small nuclear RNAs, respectively. SnoRNAs are increasingly being implicated in regulation of new types of post-transcriptional processes, for example rRNA acetylation, modulation of splicing patterns, control of mRNA abundance and translational efficiency, or they themselves are processed to shorter stable RNA species that seem to be the principal or alternative bioactive isoform. Intriguingly, some display unusual cellular localization under exogenous stimuli, or tissue-specific distribution. Here, we discuss the new and unforeseen roles attributed to snoRNAs, focusing on the presumed mechanisms of action. Furthermore, we review the experimental approaches to study snoRNA function, including high resolution RNA:protein and RNA:RNA interaction mapping, techniques for analyzing modifications on targeted RNAs, and cellular and animal models used in snoRNA biology research.
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Affiliation(s)
- Tomaž Bratkovič
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva cesta 7, SI1000 Ljubljana, Slovenia
| | - Janja Božič
- Jozef Stefan Institute, Department of Biotechnology, Jamova cesta 39, SI1000 Ljubljana, Slovenia.,Biomedical Research Institute BRIS, Puhova ulica 10, SI1000 Ljubljana, Slovenia
| | - Boris Rogelj
- University of Ljubljana, Faculty of Pharmacy, Aškerčeva cesta 7, SI1000 Ljubljana, Slovenia.,Jozef Stefan Institute, Department of Biotechnology, Jamova cesta 39, SI1000 Ljubljana, Slovenia.,Biomedical Research Institute BRIS, Puhova ulica 10, SI1000 Ljubljana, Slovenia.,University of Ljubljana, Faculty of Chemistry and Chemical Technology, Večna pot 113, SI1000 Ljubljana, Slovenia
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17
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Filippova JA, Matveeva AM, Zhuravlev ES, Balakhonova EA, Prokhorova DV, Malanin SJ, Shah Mahmud R, Grigoryeva TV, Anufrieva KS, Semenov DV, Vlassov VV, Stepanov GA. Are Small Nucleolar RNAs "CRISPRable"? A Report on Box C/D Small Nucleolar RNA Editing in Human Cells. Front Pharmacol 2019; 10:1246. [PMID: 31780925 PMCID: PMC6856654 DOI: 10.3389/fphar.2019.01246] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/27/2019] [Indexed: 01/20/2023] Open
Abstract
CRISPR technologies are nowadays widely used for targeted knockout of numerous protein-coding genes and for the study of various processes and metabolic pathways in human cells. Most attention in the genome editing field is now focused on the cleavage of protein-coding genes or genes encoding long non-coding RNAs (lncRNAs), while the studies on targeted knockout of intron-encoded regulatory RNAs are sparse. Small nucleolar RNAs (snoRNAs) present a class of non-coding RNAs encoded within the introns of various host genes and involved in post-transcriptional maturation of ribosomal RNAs (rRNAs) in eukaryotic cells. Box C/D snoRNAs direct 2'-O-methylation of rRNA nucleotides. These short RNAs have specific elements in their structure, namely, boxes C and D, and a target-recognizing region. Here, we present the study devoted to CRISPR/Cas9-mediated editing of box C/D snoRNA genes in Gas5. We obtained monoclonal cell lines carrying mutations in snoRNA genes and analyzed the levels of the mutant box C/D snoRNA as well as the 2'-O-methylation status of the target rRNA nucleotide in the obtained cells. Mutations in SNORD75 in the obtained monoclonal cell line were shown to result in aberrant splicing of Gas5 with exclusion of exons 3 to 5, which was confirmed by RT-PCR and RNA-Seq. The obtained results suggest that SNORD75 contains an element for binding of some factors regulating maturation of Gas5 pre-lncRNA. We suggest that METTL3/METTL14 is among such factors, and m6A-methylation pathways are involved in regulation of Gas5 splicing. Our results shell light on the role of SNORDs in regulating splicing of the host gene.
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Affiliation(s)
- Julia A Filippova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Anastasiya M Matveeva
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Evgenii S Zhuravlev
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Evgenia A Balakhonova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Daria V Prokhorova
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
| | - Sergey J Malanin
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Raihan Shah Mahmud
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Tatiana V Grigoryeva
- Institute of Fundamental Medicine and Biology, Kazan Federal University, Kazan, Russia
| | - Ksenia S Anufrieva
- Department of Biological and Medical Physics, Moscow Institute of Physics and Technology (State University), Moscow, Russia.,Laboratory of Cell Biology, Federal Research and Clinical Center of Physical-Chemical Medicine, Federal Medical Biological Agency, Moscow, Russia
| | - Dmitry V Semenov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Valentin V Vlassov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Grigory A Stepanov
- Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia.,Department of Natural Sciences, Novosibirsk State University, Novosibirsk, Russia
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18
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Farley-Barnes KI, Ogawa LM, Baserga SJ. Ribosomopathies: Old Concepts, New Controversies. Trends Genet 2019; 35:754-767. [PMID: 31376929 PMCID: PMC6852887 DOI: 10.1016/j.tig.2019.07.004] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 07/02/2019] [Accepted: 07/09/2019] [Indexed: 12/30/2022]
Abstract
Ribosomopathies are a diverse subset of diseases caused by reduced expression of, or mutations in, factors necessary for making ribosomes, the protein translation machinery in the cell. Despite the ubiquitous need for ribosomes in all cell types, ribosomopathies manifest with tissue-specific defects and sometimes increased cancer susceptibility, but few treatments target the underlying cause. By highlighting new research in the field, we review current hypotheses for the basis of this tissue specificity. Based on new work, we broaden our understanding of the role of ribosome biogenesis in diverse tissue types throughout embryonic development. We also pose the question of whether previously described human conditions such as aging can be at least partially attributed to defects in making ribosomes.
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Affiliation(s)
- Katherine I Farley-Barnes
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Lisa M Ogawa
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Susan J Baserga
- Department of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Genetics, Yale University School of Medicine, New Haven, CT 06520, USA; Department of Therapeutic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA.
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19
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Gaviraghi M, Vivori C, Tonon G. How Cancer Exploits Ribosomal RNA Biogenesis: A Journey beyond the Boundaries of rRNA Transcription. Cells 2019; 8:cells8091098. [PMID: 31533350 PMCID: PMC6769540 DOI: 10.3390/cells8091098] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/13/2019] [Accepted: 09/15/2019] [Indexed: 02/06/2023] Open
Abstract
The generation of new ribosomes is a coordinated process essential to sustain cell growth. As such, it is tightly regulated according to cell needs. As cancer cells require intense protein translation to ensure their enhanced growth rate, they exploit various mechanisms to boost ribosome biogenesis. In this review, we will summarize how oncogenes and tumor suppressors modulate the biosynthesis of the RNA component of ribosomes, starting from the description of well-characterized pathways that converge on ribosomal RNA transcription while including novel insights that reveal unexpected regulatory networks hacked by cancer cells to unleash ribosome production.
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Affiliation(s)
- Marco Gaviraghi
- Experimental Imaging Center; Ospedale San Raffaele, 20132 Milan, Italy.
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, 20132 Milan, Italy.
| | - Claudia Vivori
- Centre for Genomic Regulation (CRG), The Barcelona Institute for Science and Technology, 08003 Barcelona, Spain.
| | - Giovanni Tonon
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, 20132 Milan, Italy.
- Center for Translational Genomics and Bioinformatics, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, 20132 Milan, Italy.
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20
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Liang J, Wen J, Huang Z, Chen XP, Zhang BX, Chu L. Small Nucleolar RNAs: Insight Into Their Function in Cancer. Front Oncol 2019; 9:587. [PMID: 31338327 PMCID: PMC6629867 DOI: 10.3389/fonc.2019.00587] [Citation(s) in RCA: 149] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 06/17/2019] [Indexed: 02/04/2023] Open
Abstract
Small nucleolar RNAs (SnoRNAs) are a class of non-coding RNAs divided into two classes: C/D box snoRNAs and H/ACA box snoRNAs. The canonical function of C/D box and H/ACA box snoRNAs are 2'-O-ribose methylation and pseudouridylation of ribosomal RNAs (rRNAs), respectively. Emerging evidence has demonstrated that snoRNAs are involved in various physiological and pathological cellular processes. Mutations and aberrant expression of snoRNAs have been reported in cell transformation, tumorigenesis, and metastasis, indicating that snoRNAs may serve as biomarkers and/or therapeutic targets of cancer. Hence, further study of the functions and underlying mechanism of snoRNAs is valuable. In this review, we summarize the biogenesis and functions of snoRNAs, as well as the association of snoRNAs in different types of cancers and their potential roles in cancer diagnosis and therapy.
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Affiliation(s)
- Junnan Liang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jingyuan Wen
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhao Huang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiao-Ping Chen
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bi-Xiang Zhang
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Liang Chu
- Hepatic Surgery Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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21
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Bohnsack KE, Bohnsack MT. Uncovering the assembly pathway of human ribosomes and its emerging links to disease. EMBO J 2019; 38:e100278. [PMID: 31268599 PMCID: PMC6600647 DOI: 10.15252/embj.2018100278] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 02/18/2019] [Accepted: 04/26/2019] [Indexed: 12/12/2022] Open
Abstract
The essential cellular process of ribosome biogenesis is at the nexus of various signalling pathways that coordinate protein synthesis with cellular growth and proliferation. The fact that numerous diseases are caused by defects in ribosome assembly underscores the importance of obtaining a detailed understanding of this pathway. Studies in yeast have provided a wealth of information about the fundamental principles of ribosome assembly, and although many features are conserved throughout eukaryotes, the larger size of human (pre-)ribosomes, as well as the evolution of additional regulatory networks that can modulate ribosome assembly and function, have resulted in a more complex assembly pathway in humans. Notably, many ribosome biogenesis factors conserved from yeast appear to have subtly different or additional functions in humans. In addition, recent genome-wide, RNAi-based screens have identified a plethora of novel factors required for human ribosome biogenesis. In this review, we discuss key aspects of human ribosome production, highlighting differences to yeast, links to disease, as well as emerging concepts such as extra-ribosomal functions of ribosomal proteins and ribosome heterogeneity.
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Affiliation(s)
- Katherine E Bohnsack
- Department of Molecular BiologyUniversity Medical Center GöttingenGöttingenGermany
| | - Markus T Bohnsack
- Department of Molecular BiologyUniversity Medical Center GöttingenGöttingenGermany
- Göttingen Center for Molecular BiosciencesGeorg‐August UniversityGöttingenGermany
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22
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Andersen KL, Nielsen H. Knock-Down of a Novel snoRNA in Tetrahymena Reveals a Dual Role in 5.8S rRNA Processing and Generation of a 26S rRNA Fragment. Biomolecules 2018; 8:E128. [PMID: 30380771 PMCID: PMC6315972 DOI: 10.3390/biom8040128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 10/24/2018] [Accepted: 10/25/2018] [Indexed: 11/30/2022] Open
Abstract
In eukaryotes, 18S, 5.8S, and 28S rRNAs are transcribed as precursor molecules that undergo extensive modification and nucleolytic processing to form the mature rRNA species. Central in the process are the small nucleolar RNAs (snoRNAs). The majority of snoRNAs guide site specific chemical modifications but a few are involved in defining pre-rRNA cleavages. Here, we describe an unusual snoRNA (TtnuCD32) belonging to the box C/D subgroup from the ciliate Tetrahymena thermophila. We show that TtnuCD32 is unlikely to function as a modification guide snoRNA and that it is critical for cell viability. Cell lines with genetic knock-down of TtnuCD32 were impaired in growth and displayed two novel and apparently unrelated phenotypes. The most prominent phenotype is the accumulation of processing intermediates of 5.8S rRNA. The second phenotype is the decrease in abundance of a ~100 nt 26S rRNA fragment of unknown function. Sequence analysis demonstrated that TtnuCD32 share features with the essential snoRNA U14 but an alternative candidate (TtnuCD25) was more closely related to other U14 sequences. This, together with the fact that the observed rRNA processing phenotypes were not similar to what has been observed in U14 depleted cells, suggests that TtnuCD32 is a U14 homolog that has gained novel functions.
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MESH Headings
- Base Sequence
- Cell Survival
- Conserved Sequence
- Gene Expression Regulation
- Gene Knockdown Techniques
- Genome
- Methylation
- Nucleic Acid Conformation
- Protozoan Proteins/chemistry
- Protozoan Proteins/metabolism
- RNA Processing, Post-Transcriptional/genetics
- RNA, Ribosomal/chemistry
- RNA, Ribosomal/genetics
- RNA, Ribosomal, 5.8S/chemistry
- RNA, Ribosomal, 5.8S/genetics
- RNA, Small Nucleolar/chemistry
- RNA, Small Nucleolar/genetics
- Tetrahymena/genetics
- RNA, Guide, CRISPR-Cas Systems
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Affiliation(s)
- Kasper L Andersen
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Ole Maaløes Vej 5, DK-2200N Copenhagen, Denmark.
- Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen, Blegdamsvej 5b, DK-2200N Copenhagen, Denmark.
| | - Henrik Nielsen
- Department of Cellular and Molecular Medicine, The Panum Institute, University of Copenhagen, Blegdamsvej 5b, DK-2200N Copenhagen, Denmark.
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23
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Gaviraghi M, Vivori C, Pareja Sanchez Y, Invernizzi F, Cattaneo A, Santoliquido BM, Frenquelli M, Segalla S, Bachi A, Doglioni C, Pelechano V, Cittaro D, Tonon G. Tumor suppressor PNRC1 blocks rRNA maturation by recruiting the decapping complex to the nucleolus. EMBO J 2018; 37:embj.201899179. [PMID: 30373810 DOI: 10.15252/embj.201899179] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 09/14/2018] [Accepted: 09/19/2018] [Indexed: 12/20/2022] Open
Abstract
Focal deletions occur frequently in the cancer genome. However, the putative tumor-suppressive genes residing within these regions have been difficult to pinpoint. To robustly identify these genes, we implemented a computational approach based on non-negative matrix factorization, NMF, and interrogated the TCGA dataset. This analysis revealed a metagene signature including a small subset of genes showing pervasive hemizygous deletions, reduced expression in cancer patient samples, and nucleolar function. Amid the genes belonging to this signature, we have identified PNRC1, a nuclear receptor coactivator. We found that PNRC1 interacts with the cytoplasmic DCP1α/DCP2 decapping machinery and hauls it inside the nucleolus. PNRC1-dependent nucleolar translocation of the decapping complex is associated with a decrease in the 5'-capped U3 and U8 snoRNA fractions, hampering ribosomal RNA maturation. As a result, PNRC1 ablates the enhanced proliferation triggered by established oncogenes such as RAS and MYC These observations uncover a previously undescribed mechanism of tumor suppression, whereby the cytoplasmic decapping machinery is hauled within nucleoli, tightly regulating ribosomal RNA maturation.
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Affiliation(s)
- Marco Gaviraghi
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Claudia Vivori
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Yerma Pareja Sanchez
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - Francesca Invernizzi
- Pathology Unit, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Angela Cattaneo
- Functional Proteomics Program, Istituto FIRC di Oncologia Molecolare (IFOM), Milan, Italy
| | - Benedetta Maria Santoliquido
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Michela Frenquelli
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Simona Segalla
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Angela Bachi
- Functional Proteomics Program, Istituto FIRC di Oncologia Molecolare (IFOM), Milan, Italy
| | - Claudio Doglioni
- Pathology Unit, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Vicent Pelechano
- Science for Life Laboratory, Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Solna, Sweden
| | - Davide Cittaro
- Center for Translational Genomics and Bioinformatics, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
| | - Giovanni Tonon
- Functional Genomics of Cancer Unit, Division of Experimental Oncology, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy .,Center for Translational Genomics and Bioinformatics, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) San Raffaele Scientific Institute, Milan, Italy
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24
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Hermens M, van der Knaap MS, Kamsteeg EJ, Willemsen MA. A brother and sister with intellectual disability and characteristic neuroimaging findings. Eur J Paediatr Neurol 2018; 22:866-869. [PMID: 29970281 DOI: 10.1016/j.ejpn.2018.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 06/11/2018] [Accepted: 06/13/2018] [Indexed: 11/24/2022]
Abstract
Leukoencephalopathy with brain calcifications and cysts (LCC) is a genetic white matter disorder, which involves the brain small blood vessels. In the absence of extra-neurological symptoms, LCC has a pathognomonic radiological phenotype. Recently, biallelic mutations in the SNORD118 gene, which is a non-protein coding gene, were discovered to cause LCC. We present here two siblings with developmental delay and a typical MRI pattern, who were diagnosed with LCC. The mutations in the SNORD118 gene were initially missed with whole exome sequencing (WES), but recognition of the MRI patterns of both children raised the suspicion of LCC and led to a genetically proven diagnosis after re-evaluation of the WES data.
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Affiliation(s)
- Marjolein Hermens
- Department of Neurology (Paediatric Neurology) and Amalia Children's Hospital, Donders Centre for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Marjo S van der Knaap
- Department of Pediatrics (Child Neurology), VU University Medical Centre, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Erik-Jan Kamsteeg
- Department of Human Genetics, Donders Centre for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Michèl A Willemsen
- Department of Neurology (Paediatric Neurology) and Amalia Children's Hospital, Donders Centre for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands
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25
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The Conserved RNA Exonuclease Rexo5 Is Required for 3' End Maturation of 28S rRNA, 5S rRNA, and snoRNAs. Cell Rep 2018; 21:758-772. [PMID: 29045842 DOI: 10.1016/j.celrep.2017.09.067] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 07/16/2017] [Accepted: 09/20/2017] [Indexed: 12/21/2022] Open
Abstract
Non-coding RNA biogenesis in higher eukaryotes has not been fully characterized. Here, we studied the Drosophila melanogaster Rexo5 (CG8368) protein, a metazoan-specific member of the DEDDh 3'-5' single-stranded RNA exonucleases, by genetic, biochemical, and RNA-sequencing approaches. Rexo5 is required for small nucleolar RNA (snoRNA) and rRNA biogenesis and is essential in D. melanogaster. Loss-of-function mutants accumulate improperly 3' end-trimmed 28S rRNA, 5S rRNA, and snoRNA precursors in vivo. Rexo5 is ubiquitously expressed at low levels in somatic metazoan cells but extremely elevated in male and female germ cells. Loss of Rexo5 leads to increased nucleolar size, genomic instability, defective ribosome subunit export, and larval death. Loss of germline expression compromises gonadal growth and meiotic entry during germline development.
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26
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Wang H, Wang K, Du Q, Wang Y, Fu Z, Guo Z, Kang D, Li WX, Tang J. Maize Urb2 protein is required for kernel development and vegetative growth by affecting pre-ribosomal RNA processing. THE NEW PHYTOLOGIST 2018; 218:1233-1246. [PMID: 29479724 DOI: 10.1111/nph.15057] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Accepted: 01/18/2018] [Indexed: 06/08/2023]
Abstract
Ribosome biogenesis is a fundamental process in eukaryotic cells. Although Urb2 protein has been implicated in ribosome biogenesis in yeast, the Urb2 domain is loosely conserved between plants and yeast, and the function of Urb2 protein in plants remains unknown. Here, we isolated a maize mutant, designated as urb2, with defects in kernel development and vegetative growth. Positional cloning and transgenic analysis revealed that urb2 encodes an Urb2 domain-containing protein. Compared with the wild-type (WT), the urb2 mutant showed decreased ratios of 60S/40S and 80S/40S and increased ratios of polyribosomes. The pre-rRNA intermediates of 35/33S rRNA, P-A3 and 18S-A3 were significantly accumulated in the urb2 mutant. Transcriptome profiling of the urb2 mutant indicated that ZmUrb2 affects the expression of a number of ribosome-related genes. We further demonstrated that natural variations in ZmUrb2 are significantly associated with maize kernel length. The overall results indicate that, by affecting pre-rRNA processing, the Urb2 protein is required for ribosome biogenesis in maize.
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Affiliation(s)
- Hongqiu Wang
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
- Beijing Key Laboratory of Crop Genetic Improvement, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Kai Wang
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Qingguo Du
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yafei Wang
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Zhiyuan Fu
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Zhanyong Guo
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
| | - Dingming Kang
- Beijing Key Laboratory of Crop Genetic Improvement, College of Agriculture and Biotechnology, China Agricultural University, Beijing, 100193, China
| | - Wen-Xue Li
- National Engineering Laboratory for Crop Molecular Breeding, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Jihua Tang
- National Key Laboratory of Wheat and Maize Crop Science, Collaborative Innovation Center of Henan Grain Crops, College of Agronomy, Henan Agricultural University, Zhengzhou, 450002, China
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27
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Langhendries JL, Nicolas E, Doumont G, Goldman S, Lafontaine DLJ. The human box C/D snoRNAs U3 and U8 are required for pre-rRNA processing and tumorigenesis. Oncotarget 2018; 7:59519-59534. [PMID: 27517747 PMCID: PMC5312328 DOI: 10.18632/oncotarget.11148] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Accepted: 06/30/2016] [Indexed: 01/05/2023] Open
Abstract
Small nucleolar RNAs (snoRNAs) are emerging as a novel class of proto-oncogenes and tumor suppressors; their involvement in tumorigenesis remains unclear. The box C/D snoRNAs U3 and U8 are upregulated in breast cancers. Here we characterize the function of human U3 and U8 in ribosome biogenesis, nucleolar structure, and tumorigenesis. We show in breast (MCF-7) and lung (H1944) cancer cells that U3 and U8 are required for pre-rRNA processing reactions leading, respectively, to synthesis of the small and large ribosomal subunits. U3 or U8 depletion triggers a remarkably potent p53-dependent anti-tumor stress response involving the ribosomal proteins uL5 (RPL11) and uL18 (RPL5). Interestingly, the nucleolar structure is more sensitive to perturbations in lung cancer than in breast cancer cells. We reveal in a mouse xenograft model that the tumorigenic potential of cancer cells is reduced in the case of U3 suppression and totally abolished upon U8 depletion. Tumors derived from U3-knockdown cells displayed markedly lower metabolic volume and activity than tumors derived from aggressive control cancer cells. Unexpectedly, metabolic tracer uptake by U3-suppressed tumors appeared more heterogeneous, indicating distinctive tumor growth properties that may reflect non-conventional regulatory functions of U3 (or fragments derived from it) in mRNA metabolism.
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Affiliation(s)
- Jean-Louis Langhendries
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S.-FNRS), Université Libre de Bruxelles (ULB), BioPark Campus, Gosselies, Belgium
| | - Emilien Nicolas
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S.-FNRS), Université Libre de Bruxelles (ULB), BioPark Campus, Gosselies, Belgium
| | - Gilles Doumont
- Center for Microscopy and Molecular Imaging (CMMI), BioPark campus, Université Libre de Bruxelles, Belgium
| | - Serge Goldman
- Nuclear Medecine, Erasme Hospital, Université Libre de Bruxelles, Belgium.,Center for Microscopy and Molecular Imaging (CMMI), BioPark campus, Université Libre de Bruxelles, Belgium
| | - Denis L J Lafontaine
- RNA Molecular Biology, Fonds de la Recherche Scientifique (F.R.S.-FNRS), Université Libre de Bruxelles (ULB), BioPark Campus, Gosselies, Belgium.,Center for Microscopy and Molecular Imaging (CMMI), BioPark campus, Université Libre de Bruxelles, Belgium
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28
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Tomecki R, Sikorski PJ, Zakrzewska-Placzek M. Comparison of preribosomal RNA processing pathways in yeast, plant and human cells - focus on coordinated action of endo- and exoribonucleases. FEBS Lett 2017; 591:1801-1850. [PMID: 28524231 DOI: 10.1002/1873-3468.12682] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/14/2017] [Accepted: 05/15/2017] [Indexed: 12/17/2022]
Abstract
Proper regulation of ribosome biosynthesis is mandatory for cellular adaptation, growth and proliferation. Ribosome biogenesis is the most energetically demanding cellular process, which requires tight control. Abnormalities in ribosome production have severe consequences, including developmental defects in plants and genetic diseases (ribosomopathies) in humans. One of the processes occurring during eukaryotic ribosome biogenesis is processing of the ribosomal RNA precursor molecule (pre-rRNA), synthesized by RNA polymerase I, into mature rRNAs. It must not only be accurate but must also be precisely coordinated with other phenomena leading to the synthesis of functional ribosomes: RNA modification, RNA folding, assembly with ribosomal proteins and nucleocytoplasmic RNP export. A multitude of ribosome biogenesis factors ensure that these events take place in a correct temporal order. Among them are endo- and exoribonucleases involved in pre-rRNA processing. Here, we thoroughly present a wide spectrum of ribonucleases participating in rRNA maturation, focusing on their biochemical properties, regulatory mechanisms and substrate specificity. We also discuss cooperation between various ribonucleolytic activities in particular stages of pre-rRNA processing, delineating major similarities and differences between three representative groups of eukaryotes: yeast, plants and humans.
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Affiliation(s)
- Rafal Tomecki
- Laboratory of RNA Biology and Functional Genomics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland.,Department of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Poland
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29
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Blewett NH, Iben JR, Gaidamakov S, Maraia RJ. La Deletion from Mouse Brain Alters Pre-tRNA Metabolism and Accumulation of Pre-5.8S rRNA, with Neuron Death and Reactive Astrocytosis. Mol Cell Biol 2017; 37:e00588-16. [PMID: 28223366 PMCID: PMC5477551 DOI: 10.1128/mcb.00588-16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 12/01/2016] [Accepted: 02/06/2017] [Indexed: 12/20/2022] Open
Abstract
Human La antigen (Sjögren's syndrome antigen B [SSB]) is an abundant multifunctional RNA-binding protein. In the nucleoplasm, La binds to and protects from 3' exonucleases, the ends of precursor tRNAs, and other transcripts synthesized by RNA polymerase III and facilitates their maturation, while a nucleolar isoform has been implicated in rRNA biogenesis by multiple independent lines of evidence. We showed previously that conditional La knockout (La cKO) from mouse cortex neurons results in defective tRNA processing, although the pathway(s) involved in neuronal loss thereafter was unknown. Here, we demonstrate that La is stably associated with a spliced pre-tRNA intermediate. Microscopic evidence of aberrant nuclear accumulation of 5.8S rRNA in La cKO is supported by a 10-fold increase in a pre-5.8S rRNA intermediate. To identify pathways involved in subsequent neurodegeneration and loss of brain mass in the cKO cortex, we employed mRNA sequencing (mRNA-Seq), immunohistochemistry, and other approaches. This revealed robust enrichment of immune and astrocyte reactivity in La cKO cortex. Immunohistochemistry, including temporal analyses, demonstrated neurodegeneration, followed by astrocyte invasion associated with immune response and decreasing cKO cortex size over time. Thus, deletion of La from postmitotic neurons results in defective pre-tRNA and pre-rRNA processing and progressive neurodegeneration with loss of cortical brain mass.
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Affiliation(s)
- Nathan H Blewett
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Rockville, Maryland, USA
| | - James R Iben
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Rockville, Maryland, USA
| | - Sergei Gaidamakov
- Intramural Research Program, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Rockville, Maryland, USA
| | - Richard J Maraia
- Commissioned Corps, U.S. Public Health Service, Rockville, Maryland, USA
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30
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Iwama K, Mizuguchi T, Takanashi J, Shibayama H, Shichiji M, Ito S, Oguni H, Yamamoto T, Sekine A, Nagamine S, Ikeda Y, Nishida H, Kumada S, Yoshida T, Awaya T, Tanaka R, Chikuchi R, Niwa H, Oka Y, Miyatake S, Nakashima M, Takata A, Miyake N, Ito S, Saitsu H, Matsumoto N. Identification of novel
SNORD118
mutations in seven patients with leukoencephalopathy with brain calcifications and cysts. Clin Genet 2017; 92:180-187. [DOI: 10.1111/cge.12991] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Revised: 01/31/2017] [Accepted: 01/31/2017] [Indexed: 02/06/2023]
Affiliation(s)
- Kazuhiro Iwama
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
- Department of Pediatrics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Takeshi Mizuguchi
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Jun‐ichi Takanashi
- Department of Pediatrics and Pediatric Neurology Tokyo Women's Medical University, Yachiyo Medical Center Yachiyo Japan
| | | | - Minobu Shichiji
- Department of Pediatrics Tokyo Women's Medical University Tokyo Japan
| | - Susumu Ito
- Department of Pediatrics Tokyo Women's Medical University Tokyo Japan
| | - Hirokazu Oguni
- Department of Pediatrics Tokyo Women's Medical University Tokyo Japan
| | - Toshiyuki Yamamoto
- Institute of Medical Genetics Tokyo Women's Medical University Tokyo Japan
| | - Akiko Sekine
- Department of Neurology Gunma University Graduate School of Medicine Maebashi Japan
| | - Shun Nagamine
- Department of Neurology Gunma University Graduate School of Medicine Maebashi Japan
| | - Yoshio Ikeda
- Department of Neurology Gunma University Graduate School of Medicine Maebashi Japan
| | - Hiroya Nishida
- Department of Neuropediatrics Tokyo Metropolitan Neurological Hospital Tokyo Japan
| | - Satoko Kumada
- Department of Neuropediatrics Tokyo Metropolitan Neurological Hospital Tokyo Japan
| | - Takeshi Yoshida
- Department of Pediatrics Kyoto University Graduate School of Medicine Kyoto Japan
| | - Tomonari Awaya
- Department of Pediatrics Kyoto University Graduate School of Medicine Kyoto Japan
- Department of Anatomy and Developmental Biology Kyoto University Graduate School of Medicine Kyoto Japan
| | - Ryuta Tanaka
- Department of Child Health, Faculty of Medicine University of Tsukuba Tsukuba Japan
| | - Ryo Chikuchi
- Department of Neurology Kariya Toyota General Hospital Kariya Japan
| | - Hisayoshi Niwa
- Department of Neurology Kariya Toyota General Hospital Kariya Japan
| | - Yu‐ichi Oka
- Department of Neurosurgery Nagoya City University Hospital Nagoya Japan
| | - Satoko Miyatake
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Mitsuko Nakashima
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Atsushi Takata
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Noriko Miyake
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Shuichi Ito
- Department of Pediatrics, Graduate School of Medicine Yokohama City University Yokohama Japan
| | - Hirotomo Saitsu
- Department of Biochemistry Hamamatsu University School of Medicine Hamamatsu Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Graduate School of Medicine Yokohama City University Yokohama Japan
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31
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Gumienny R, Jedlinski DJ, Schmidt A, Gypas F, Martin G, Vina-Vilaseca A, Zavolan M. High-throughput identification of C/D box snoRNA targets with CLIP and RiboMeth-seq. Nucleic Acids Res 2017; 45:2341-2353. [PMID: 28031372 PMCID: PMC5389715 DOI: 10.1093/nar/gkw1321] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Revised: 12/08/2016] [Accepted: 12/19/2016] [Indexed: 01/02/2023] Open
Abstract
High-throughput sequencing has greatly facilitated the discovery of long and short non-coding RNAs (ncRNAs), which frequently guide ribonucleoprotein complexes to RNA targets, to modulate their metabolism and expression. However, for many ncRNAs, the targets remain to be discovered. In this study, we developed computational methods to map C/D box snoRNA target sites using data from core small nucleolar ribonucleoprotein crosslinking and immunoprecipitation and from transcriptome-wide mapping of 2΄-O-ribose methylation sites. We thereby assigned the snoRNA guide to a known methylation site in the 18S rRNA, we uncovered a novel partially methylated site in the 28S ribosomal RNA, and we captured a site in the 28S rRNA in interaction with multiple snoRNAs. Although we also captured mRNAs in interaction with snoRNAs, we did not detect 2΄-O-methylation of these targets. Our study provides an integrated approach to the comprehensive characterization of 2΄-O-methylation targets of snoRNAs in species beyond those in which these interactions have been traditionally studied and contributes to the rapidly developing field of 'epitranscriptomics'.
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MESH Headings
- Algorithms
- Base Sequence
- Cross-Linking Reagents/chemistry
- Databases, Genetic
- High-Throughput Nucleotide Sequencing/methods
- Immunoprecipitation
- Methylation
- Protein Binding
- RNA, Ribosomal, 18S/genetics
- RNA, Ribosomal, 18S/metabolism
- RNA, Ribosomal, 28S/genetics
- RNA, Ribosomal, 28S/metabolism
- RNA, Small Nucleolar/genetics
- RNA, Small Nucleolar/metabolism
- Ribonucleoproteins, Small Nucleolar/genetics
- Ribonucleoproteins, Small Nucleolar/metabolism
- Ribose/metabolism
- Software
- Transcriptome
- RNA, Guide, CRISPR-Cas Systems
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Affiliation(s)
- Rafal Gumienny
- Computational and Systems Biology, Biozentrum, University of Basel, Switzerland
- Swiss Institute of Bioinformatics, Biozentrum, University of Basel, Switzerland
| | | | - Alexander Schmidt
- Proteomics Core Facility, Biozentrum, University of Basel, Switzerland
| | - Foivos Gypas
- Computational and Systems Biology, Biozentrum, University of Basel, Switzerland
- Swiss Institute of Bioinformatics, Biozentrum, University of Basel, Switzerland
| | - Georges Martin
- Computational and Systems Biology, Biozentrum, University of Basel, Switzerland
| | - Arnau Vina-Vilaseca
- Computational and Systems Biology, Biozentrum, University of Basel, Switzerland
| | - Mihaela Zavolan
- Computational and Systems Biology, Biozentrum, University of Basel, Switzerland
- Swiss Institute of Bioinformatics, Biozentrum, University of Basel, Switzerland
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32
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Ismael H, Altmeyer S, Stahl H. Regulation of the U3-, U8-, and U13snoRNA Expression by the DEAD Box Proteins Ddx5/Ddx17 with Consequences for Cell Proliferation and Survival. Noncoding RNA 2016; 2:ncrna2040011. [PMID: 29657268 PMCID: PMC5831926 DOI: 10.3390/ncrna2040011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 07/22/2016] [Accepted: 08/09/2016] [Indexed: 12/17/2022] Open
Abstract
Small nucleolar RNAs (snoRNAs) in cooperation with their associated proteins (snoRNPs) contribute to the maturation of ribosomal RNA, transfer RNA, and other transcripts. Most snoRNPs mediate chemical base modifications of their RNA substrates, and a few others, like those formed by the C/D snoRNAs U3, U8, and U13, are needed for the structural organization and maturation of primary transcripts. The U3-, U8-, and U13snoRNAs are encoded by autonomous genes, and our knowledge about their expression regulation is limited. In this study, a significant increase in the concentrations of U3-, U8-, and U13snoRNA after a knockdown of DEAD box proteins Ddx5/Ddx17 in HeLa cells is observed. These alterations are shown to be caused by transcriptional suppression mediated by Ddx5/Ddx17 via histone deacetylase 1 in a promoter-dependent way. The biological function of this expression control may be related to the role of Ddx5/Ddx17 in cell proliferation. The U3snoRNA is shown here to be essential for the proliferation and viability of human cells. Moreover, it was found that U3snoRNA interacts with Argonaute 2 in the RNA-induced silencing complexes (RISC), pointing to a microRNA-like function. For this reason, the 3′ untranslated region of the A-kinase anchor protein 9 (AKAP9)-mRNA could be identified as a potential target.
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Affiliation(s)
- Hala Ismael
- Department of Medical Biochemistry and Molecular Biology, University of Saarland, Medical Center, Building 45, 66421 Homburg, Germany.
| | - Simone Altmeyer
- Department of Medical Biochemistry and Molecular Biology, University of Saarland, Medical Center, Building 45, 66421 Homburg, Germany.
| | - Hans Stahl
- Department of Medical Biochemistry and Molecular Biology, University of Saarland, Medical Center, Building 45, 66421 Homburg, Germany.
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33
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RNA Duplex Map in Living Cells Reveals Higher-Order Transcriptome Structure. Cell 2016; 165:1267-1279. [PMID: 27180905 DOI: 10.1016/j.cell.2016.04.028] [Citation(s) in RCA: 413] [Impact Index Per Article: 51.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 03/03/2016] [Accepted: 04/05/2016] [Indexed: 02/06/2023]
Abstract
RNA has the intrinsic property to base pair, forming complex structures fundamental to its diverse functions. Here, we develop PARIS, a method based on reversible psoralen crosslinking for global mapping of RNA duplexes with near base-pair resolution in living cells. PARIS analysis in three human and mouse cell types reveals frequent long-range structures, higher-order architectures, and RNA-RNA interactions in trans across the transcriptome. PARIS determines base-pairing interactions on an individual-molecule level, revealing pervasive alternative conformations. We used PARIS-determined helices to guide phylogenetic analysis of RNA structures and discovered conserved long-range and alternative structures. XIST, a long noncoding RNA (lncRNA) essential for X chromosome inactivation, folds into evolutionarily conserved RNA structural domains that span many kilobases. XIST A-repeat forms complex inter-repeat duplexes that nucleate higher-order assembly of the key epigenetic silencing protein SPEN. PARIS is a generally applicable and versatile method that provides novel insights into the RNA structurome and interactome. VIDEO ABSTRACT.
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Rapid and efficient elimination of specific nuclear noncoding RNAs in mammalian cells with antisense oligonucleotides. Methods Mol Biol 2015; 1206:149-56. [PMID: 25240894 DOI: 10.1007/978-1-4939-1369-5_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
A wide variety of noncoding RNAs are thought to play fundamental and regulatory functions in the mammalian cell nucleus, although their primary functions have yet to be elucidated. Here, we describe a method for the rapid and efficient elimination of specific nuclear noncoding RNAs in mammalian cells using chemically modified antisense oligonucleotides, which may facilitate the functional assessment of nuclear ncRNAs.
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Dupuis-Sandoval F, Poirier M, Scott MS. The emerging landscape of small nucleolar RNAs in cell biology. WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 6:381-97. [PMID: 25879954 PMCID: PMC4696412 DOI: 10.1002/wrna.1284] [Citation(s) in RCA: 155] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 03/18/2015] [Accepted: 03/20/2015] [Indexed: 01/07/2023]
Abstract
Small nucleolar RNAs (snoRNAs) are a large class of small noncoding RNAs present in all eukaryotes sequenced thus far. As a family, they have been well characterized as playing a central role in ribosome biogenesis, guiding either the sequence-specific chemical modification of pre-rRNA (ribosomal RNA) or its processing. However, in higher eukaryotes, numerous orphan snoRNAs were described over a decade ago, with no known target or ascribed function, suggesting the possibility of alternative cellular functionality. In recent years, thanks in great part to advances in sequencing methodologies, we have seen many examples of the diversity that exists in the snoRNA family on multiple levels. In this review, we discuss the identification of novel snoRNA members, of unexpected binding partners, as well as the clarification and extension of the snoRNA target space and the characterization of diverse new noncanonical functions, painting a new and extended picture of the snoRNA landscape. Under the deluge of novel features and functions that have recently come to light, snoRNAs emerge as a central, dynamic, and highly versatile group of small regulatory RNAs. WIREs RNA 2015, 6:381–397. doi: 10.1002/wrna.1284
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Affiliation(s)
- Fabien Dupuis-Sandoval
- Biochemistry Department, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Mikaël Poirier
- Biochemistry Department, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
| | - Michelle S Scott
- Biochemistry Department and RNA Group, Faculty of Medicine and Health Sciences, University of Sherbrooke, Sherbrooke, Canada
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Lafontaine DLJ. Noncoding RNAs in eukaryotic ribosome biogenesis and function. Nat Struct Mol Biol 2015; 22:11-9. [PMID: 25565028 DOI: 10.1038/nsmb.2939] [Citation(s) in RCA: 174] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 11/26/2014] [Indexed: 12/22/2022]
Abstract
The ribosome, central to protein synthesis in all cells, is a complex multicomponent assembly with rRNA at its functional core. During the process of ribosome biogenesis, diverse noncoding RNAs participate in controlling the quantity and quality of this rRNA. In this Review, I discuss the multiple roles assumed by noncoding RNAs during the different steps of ribosome biogenesis and how they contribute to the generation of ribosome heterogeneity, which affects normal and pathophysiological processes.
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Affiliation(s)
- Denis L J Lafontaine
- RNA Molecular Biology, Fonds National de la Recherche Scientifique, Université Libre de Bruxelles, Brussels, Belgium
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The ribosome biogenesis factor Nol11 is required for optimal rDNA transcription and craniofacial development in Xenopus. PLoS Genet 2015; 11:e1005018. [PMID: 25756904 PMCID: PMC4354908 DOI: 10.1371/journal.pgen.1005018] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 01/22/2015] [Indexed: 01/30/2023] Open
Abstract
The production of ribosomes is ubiquitous and fundamental to life. As such, it is surprising that defects in ribosome biogenesis underlie a growing number of symptomatically distinct inherited disorders, collectively called ribosomopathies. We previously determined that the nucleolar protein, NOL11, is essential for optimal pre-rRNA transcription and processing in human tissue culture cells. However, the role of NOL11 in the development of a multicellular organism remains unknown. Here, we reveal a critical function for NOL11 in vertebrate ribosome biogenesis and craniofacial development. Nol11 is strongly expressed in the developing cranial neural crest (CNC) of both amphibians and mammals, and knockdown of Xenopus nol11 results in impaired pre-rRNA transcription and processing, increased apoptosis, and abnormal development of the craniofacial cartilages. Inhibition of p53 rescues this skeletal phenotype, but not the underlying ribosome biogenesis defect, demonstrating an evolutionarily conserved control mechanism through which ribosome-impaired craniofacial cells are removed. Excessive activation of this mechanism impairs craniofacial development. Together, our findings reveal a novel requirement for Nol11 in craniofacial development, present the first frog model of a ribosomopathy, and provide further insight into the clinically important relationship between specific ribosome biogenesis proteins and craniofacial cell survival.
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Coleman AW. Nuclear rRNA transcript processing versus internal transcribed spacer secondary structure. Trends Genet 2015; 31:157-63. [DOI: 10.1016/j.tig.2015.01.002] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 01/06/2015] [Accepted: 01/06/2015] [Indexed: 11/26/2022]
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Thorenoor N, Slaby O. Small nucleolar RNAs functioning and potential roles in cancer. Tumour Biol 2014; 36:41-53. [DOI: 10.1007/s13277-014-2818-8] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 11/04/2014] [Indexed: 11/27/2022] Open
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Arabidopsis protein arginine methyltransferase 3 is required for ribosome biogenesis by affecting precursor ribosomal RNA processing. Proc Natl Acad Sci U S A 2014; 111:16190-5. [PMID: 25352672 DOI: 10.1073/pnas.1412697111] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Ribosome biogenesis is a fundamental and tightly regulated cellular process, including synthesis, processing, and assembly of rRNAs with ribosomal proteins. Protein arginine methyltransferases (PRMTs) have been implicated in many important biological processes, such as ribosome biogenesis. Two alternative precursor rRNA (pre-rRNA) processing pathways coexist in yeast and mammals; however, how PRMT affects ribosome biogenesis remains largely unknown. Here we show that Arabidopsis PRMT3 (AtPRMT3) is required for ribosome biogenesis by affecting pre-rRNA processing. Disruption of AtPRMT3 results in pleiotropic developmental defects, imbalanced polyribosome profiles, and aberrant pre-rRNA processing. We further identify an alternative pre-rRNA processing pathway in Arabidopsis and demonstrate that AtPRMT3 is required for the balance of these two pathways to promote normal growth and development. Our work uncovers a previously unidentified function of PRMT in posttranscriptional regulation of rRNA, revealing an extra layer of complexity in the regulation of ribosome biogenesis.
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Henras AK, Plisson-Chastang C, O'Donohue MF, Chakraborty A, Gleizes PE. An overview of pre-ribosomal RNA processing in eukaryotes. WILEY INTERDISCIPLINARY REVIEWS-RNA 2014; 6:225-42. [PMID: 25346433 PMCID: PMC4361047 DOI: 10.1002/wrna.1269] [Citation(s) in RCA: 385] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 08/04/2014] [Accepted: 08/29/2014] [Indexed: 12/23/2022]
Abstract
Ribosomal RNAs are the most abundant and universal noncoding RNAs in living organisms. In eukaryotes, three of the four ribosomal RNAs forming the 40S and 60S subunits are borne by a long polycistronic pre-ribosomal RNA. A complex sequence of processing steps is required to gradually release the mature RNAs from this precursor, concomitant with the assembly of the 79 ribosomal proteins. A large set of trans-acting factors chaperone this process, including small nucleolar ribonucleoparticles. While yeast has been the gold standard for studying the molecular basis of this process, recent technical advances have allowed to further define the mechanisms of ribosome biogenesis in animals and plants. This renewed interest for a long-lasting question has been fueled by the association of several genetic diseases with mutations in genes encoding both ribosomal proteins and ribosome biogenesis factors, and by the perspective of new anticancer treatments targeting the mechanisms of ribosome synthesis. A consensus scheme of pre-ribosomal RNA maturation is emerging from studies in various kinds of eukaryotic organisms. However, major differences between mammalian and yeast pre-ribosomal RNA processing have recently come to light. WIREs RNA 2015, 6:225–242. doi: 10.1002/wrna.1269
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Affiliation(s)
- Anthony K Henras
- Laboratoire de Biologie Moléculaire Eucaryote, Université de Toulouse-Paul Sabatier CNRS, UMR 5099, Toulouse, France
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Wang M, Anikin L, Pestov DG. Two orthogonal cleavages separate subunit RNAs in mouse ribosome biogenesis. Nucleic Acids Res 2014; 42:11180-91. [PMID: 25190460 PMCID: PMC4176171 DOI: 10.1093/nar/gku787] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Ribosome biogenesis is a dynamic multistep process, many features of which are still incompletely documented. Here, we show that changes in this pathway can be captured and annotated by means of a graphic set of pre-rRNA ratios, a technique we call Ratio Analysis of Multiple Precursors (RAMP). We find that knocking down a ribosome synthesis factor produces a characteristic RAMP profile that exhibits consistency across a range of depletion levels. This facilitates the inference of affected steps and simplifies comparative analysis. We applied RAMP to examine how endonucleolytic cleavages of the mouse pre-rRNA transcript in the internal transcribed spacer 1 (ITS1) are affected by depletion of factors required for maturation of the small ribosomal subunit (Rcl1, Fcf1/Utp24, Utp23) and the large subunit (Pes1, Nog1). The data suggest that completion of early maturation in a subunit triggers its release from the common pre-rRNA transcript by stimulating cleavage at the proximal site in ITS1. We also find that splitting of pre-rRNA in the 3' region of ITS1 is prevalent in adult mouse tissues and quiescent cells, as it is in human cells. We propose a model for subunit separation during mammalian ribosome synthesis and discuss its implications for understanding pre-rRNA processing pathways.
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Affiliation(s)
- Minshi Wang
- Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084, USA Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ 08084, USA
| | - Leonid Anikin
- Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084, USA Graduate School of Biomedical Sciences, Rowan University, Stratford, NJ 08084, USA
| | - Dimitri G Pestov
- Department of Cell Biology, Rowan University School of Osteopathic Medicine, Stratford, NJ 08084, USA
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Peng Y, Yu G, Tian S, Li H. Co-expression and co-purification of archaeal and eukaryal box C/D RNPs. PLoS One 2014; 9:e103096. [PMID: 25078083 PMCID: PMC4117494 DOI: 10.1371/journal.pone.0103096] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2014] [Accepted: 06/27/2014] [Indexed: 11/18/2022] Open
Abstract
Box C/D ribonucleoprotein particles (RNPs) are 2'-O-methylation enzymes required for maturation of ribosomal and small nuclear RNA. Previous biochemical and structural studies of the box C/D RNPs were limited by the unavailability of purified intact RNPs. We developed a bacterial co-expression strategy based on the combined use of a multi-gene expression system and a tRNA-scaffold construct that allowed the expression and purification of homogeneous archaeal and human box C/D RNPs. While the co-expressed and co-purified archaeal box C/D RNP was found to be fully active in a 2'-O-methylation assay, the intact human U14 box C/D RNP showed no detectable catalytic activity, consistent with the earlier findings that assembly of eukaryotic box C/D RNPs is nonspontaneous and requires additional protein factors. Our systems provide a means for further biochemical and structural characterization of box C/D RNPs and their assembly factors.
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Affiliation(s)
- Yu Peng
- Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida, United States of America
| | - Ge Yu
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, United States of America
| | - Shaoxiong Tian
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, United States of America
| | - Hong Li
- Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida, United States of America
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, United States of America
- * E-mail:
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Thomson E, Ferreira-Cerca S, Hurt E. Eukaryotic ribosome biogenesis at a glance. J Cell Sci 2014; 126:4815-21. [PMID: 24172536 DOI: 10.1242/jcs.111948] [Citation(s) in RCA: 201] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Ribosomes play a pivotal role in the molecular life of every cell. Moreover, synthesis of ribosomes is one of the most energetically demanding of all cellular processes. In eukaryotic cells, ribosome biogenesis requires the coordinated activity of all three RNA polymerases and the orchestrated work of many (>200) transiently associated ribosome assembly factors. The biogenesis of ribosomes is a tightly regulated activity and it is inextricably linked to other fundamental cellular processes, including growth and cell division. Furthermore, recent studies have demonstrated that defects in ribosome biogenesis are associated with several hereditary diseases. In this Cell Science at a Glance article and the accompanying poster, we summarise the current knowledge on eukaryotic ribosome biogenesis, with an emphasis on the yeast model system.
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Affiliation(s)
- Emma Thomson
- Biochemistry Center (BZH), University of Heidelberg, Im Neuenheimer Feld 328, 69120 Heidelberg, Germany
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Bratkovič T, Rogelj B. The many faces of small nucleolar RNAs. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2014; 1839:438-43. [PMID: 24735946 DOI: 10.1016/j.bbagrm.2014.04.009] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 04/07/2014] [Accepted: 04/08/2014] [Indexed: 12/15/2022]
Abstract
Small nucleolar RNAs (snoRNAs) are a class of evolutionally conserved non-coding RNAs traditionally associated with nucleotide modifications in other RNA species. Acting as guides pairing with ribosomal (rRNA) and small nuclear RNAs (snRNAs), snoRNAs direct partner enzymes to specific sites for uridine isomerization or ribose methylation, thereby influencing stability, folding and protein-interacting properties of target RNAs. In recent years, however, numerous non-canonical functions have also been ascribed to certain members of the snoRNA group, ranging from regulation of mRNA editing and/or alternative splicing to posttranscriptional gene silencing by a yet poorly understood pathway that may involve microRNA-like mechanisms. While some of these intriguing snoRNAs (the so-called orphan snoRNAs) have no sequence complementarity to rRNA or snRNA, others apparently display dual functionality, performing both traditional and newly elucidated functions. Here, we review the effects elicited by non-canonical snoRNA activities.
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Affiliation(s)
- Tomaž Bratkovič
- University of Ljubljana, Faculty of Pharmacy, Department of Pharmaceutical Biology, Aškerčeva 7, SI-1000 Ljubljana, Slovenia.
| | - Boris Rogelj
- Jozef Stefan Institute, Department of Biotechnology, Jamova 39, SI-1000 Ljubljana, Slovenia.
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Burger K, Mühl B, Kellner M, Rohrmoser M, Gruber-Eber A, Windhager L, Friedel CC, Dölken L, Eick D. 4-thiouridine inhibits rRNA synthesis and causes a nucleolar stress response. RNA Biol 2013; 10:1623-30. [PMID: 24025460 DOI: 10.4161/rna.26214] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
High concentrations (> 100 µM) of the ribonucleoside analog 4-thiouridine (4sU) is widely used in methods for RNA analysis like photoactivatable-ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) and nascent messenger (m)RNA labeling (4sU-tagging). Here, we show that 4sU-tagging at low concentrations ≤ 10 µM can be used to measure production and processing of ribosomal (r)RNA. However, elevated concentrations of 4sU (> 50 µM), which are usually used for mRNA labeling experiments, inhibit production and processing of 47S rRNA. The inhibition of rRNA synthesis is accompanied by nucleoplasmic translocation of nucleolar nucleophosmin (NPM1), induction of the tumor suppressor p53, and inhibition of proliferation. We conclude that metabolic labeling of RNA by 4sU triggers a nucleolar stress response, which might influence the interpretation of results. Therefore, functional ribosome biogenesis, nucleolar integrity, and cell cycle should be addressed in 4sU labeling experiments.
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Affiliation(s)
- Kaspar Burger
- Department of Molecular Epigenetics; Helmholtz Center Munich; Center for Integrated Protein Science Munich (CIPSM); Munich, Germany
| | - Bastian Mühl
- Department of Molecular Epigenetics; Helmholtz Center Munich; Center for Integrated Protein Science Munich (CIPSM); Munich, Germany
| | - Markus Kellner
- Department of Molecular Epigenetics; Helmholtz Center Munich; Center for Integrated Protein Science Munich (CIPSM); Munich, Germany
| | - Michaela Rohrmoser
- Department of Molecular Epigenetics; Helmholtz Center Munich; Center for Integrated Protein Science Munich (CIPSM); Munich, Germany
| | - Anita Gruber-Eber
- Department of Molecular Epigenetics; Helmholtz Center Munich; Center for Integrated Protein Science Munich (CIPSM); Munich, Germany
| | - Lukas Windhager
- Institute for Informatics, Teaching and Research Unit Bioinformatics; Ludwig-Maximilians-University Munich; Munich, Germany
| | - Caroline C Friedel
- Institute for Informatics, Teaching and Research Unit Bioinformatics; Ludwig-Maximilians-University Munich; Munich, Germany
| | - Lars Dölken
- Department of Medicine; Addenbrooke's Hospital; University of Cambridge; Cambridge, UK
| | - Dirk Eick
- Department of Molecular Epigenetics; Helmholtz Center Munich; Center for Integrated Protein Science Munich (CIPSM); Munich, Germany
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Makarova JA, Ivanova SM, Tonevitsky AG, Grigoriev AI. New functions of small nucleolar RNAs. BIOCHEMISTRY (MOSCOW) 2013; 78:638-50. [DOI: 10.1134/s0006297913060096] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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48
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Burger K, Mühl B, Rohrmoser M, Coordes B, Heidemann M, Kellner M, Gruber-Eber A, Heissmeyer V, Strässer K, Eick D. Cyclin-dependent kinase 9 links RNA polymerase II transcription to processing of ribosomal RNA. J Biol Chem 2013; 288:21173-21183. [PMID: 23744076 DOI: 10.1074/jbc.m113.483719] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Ribosome biogenesis is a process required for cellular growth and proliferation. Processing of ribosomal RNA (rRNA) is highly sensitive to flavopiridol, a specific inhibitor of cyclin-dependent kinase 9 (Cdk9). Cdk9 has been characterized as the catalytic subunit of the positive transcription elongation factor b (P-TEFb) of RNA polymerase II (RNAPII). Here we studied the connection between RNAPII transcription and rRNA processing. We show that inhibition of RNAPII activity by α-amanitin specifically blocks processing of rRNA. The block is characterized by accumulation of 3' extended unprocessed 47 S rRNAs and the entire inhibition of other 47 S rRNA-specific processing steps. The transcription rate of rRNA is moderately reduced after inhibition of Cdk9, suggesting that defective 3' processing of rRNA negatively feeds back on RNAPI transcription. Knockdown of Cdk9 caused a strong reduction of the levels of RNAPII-transcribed U8 small nucleolar RNA, which is essential for 3' rRNA processing in mammalian cells. Our data demonstrate a pivotal role of Cdk9 activity for coupling of RNAPII transcription with small nucleolar RNA production and rRNA processing.
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Affiliation(s)
- Kaspar Burger
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Bastian Mühl
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Michaela Rohrmoser
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Britta Coordes
- Gene Center and Department of Biochemistry, Center for Integrated Protein Science Munich, Ludwig Maximilians University of Munich, Feodor-Lynen-Strasse 25, 81377 Munich, Germany, and
| | - Martin Heidemann
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Markus Kellner
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Anita Gruber-Eber
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Vigo Heissmeyer
- Institute of Molecular Immunology, Helmholtz Center Munich, Marchioninistrasse 25, 81377 Munich, Germany
| | - Katja Strässer
- Gene Center and Department of Biochemistry, Center for Integrated Protein Science Munich, Ludwig Maximilians University of Munich, Feodor-Lynen-Strasse 25, 81377 Munich, Germany, and
| | - Dirk Eick
- From the Department of Molecular Epigenetics, Helmholtz Center Munich, Center for Integrated Protein Science Munich, Marchioninistrasse 25, 81377 Munich, Germany,.
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Sloan KE, Mattijssen S, Lebaron S, Tollervey D, Pruijn GJM, Watkins NJ. Both endonucleolytic and exonucleolytic cleavage mediate ITS1 removal during human ribosomal RNA processing. ACTA ACUST UNITED AC 2013; 200:577-88. [PMID: 23439679 PMCID: PMC3587827 DOI: 10.1083/jcb.201207131] [Citation(s) in RCA: 110] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Human ribosome production is up-regulated during tumorogenesis and is defective in many genetic diseases (ribosomopathies). We have undertaken a detailed analysis of human precursor ribosomal RNA (pre-rRNA) processing because surprisingly little is known about this important pathway. Processing in internal transcribed spacer 1 (ITS1) is a key step that separates the rRNA components of the large and small ribosomal subunits. We report that this was initiated by endonuclease cleavage, which required large subunit biogenesis factors. This was followed by 3' to 5' exonucleolytic processing by RRP6 and the exosome, an enzyme complex not previously linked to ITS1 removal. In contrast, RNA interference-mediated knockdown of the endoribonuclease MRP did not result in a clear defect in ITS1 processing. Despite the apparently high evolutionary conservation of the pre-rRNA processing pathway and ribosome synthesis factors, each of these features of human ITS1 processing is distinct from those in budding yeast. These results also provide significant insight into the links between ribosomopathies and ribosome production in human cells.
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Affiliation(s)
- Katherine E Sloan
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, England, UK
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50
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Kaur D, Gupta AK, Kumari V, Sharma R, Bhattacharya A, Bhattacharya S. Computational prediction and validation of C/D, H/ACA and Eh_U3 snoRNAs of Entamoeba histolytica. BMC Genomics 2012; 13:390. [PMID: 22892049 PMCID: PMC3542256 DOI: 10.1186/1471-2164-13-390] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 07/25/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Small nucleolar RNAs are a highly conserved group of small RNAs found in eukaryotic cells. Genes encoding these RNAs are diversely located throughout the genome. They are functionally conserved, performing post transcriptional modification (methylation and pseudouridylation) of rRNA and other nuclear RNAs. They belong to two major categories: the C/D box and H/ACA box containing snoRNAs. U3 snoRNA is an exceptional member of C/D box snoRNAs and is involved in early processing of pre-rRNA. An antisense sequence is present in each snoRNA which guides the modification or processing of target RNA. However, some snoRNAs lack this sequence and often they are called orphan snoRNAs. RESULTS We have searched snoRNAs of Entamoeba histolytica from the genome sequence using computational programmes (snoscan and snoSeeker) and we obtained 99 snoRNAs (C/D and H/ACA box snoRNAs) along with 5 copies of Eh_U3 snoRNAs. These are located diversely in the genome, mostly in intergenic regions, while some are found in ORFs of protein coding genes, intron and UTRs. The computationally predicted snoRNAs were validated by RT-PCR and northern blotting. The expected sizes were in agreement with the observed sizes for all C/D box snoRNAs tested, while for some of the H/ACA box there was indication of processing to generate shorter products. CONCLUSION Our results showed the presence of snoRNAs in E. histolytica, an early branching eukaryote, and the structural features of E. histolytica snoRNAs were well conserved when compared with yeast and human snoRNAs. This study will help in understanding the evolution of these conserved RNAs in diverse phylogenetic groups.
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Affiliation(s)
- Devinder Kaur
- School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
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