1
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Firdous Z, Kalra S, Chattopadhyay R, Bari VK. Current insight into the role of mRNA decay pathways in fungal pathogenesis. Microbiol Res 2024; 283:127671. [PMID: 38479232 DOI: 10.1016/j.micres.2024.127671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/19/2024] [Accepted: 02/29/2024] [Indexed: 04/17/2024]
Abstract
Pathogenic fungal species can cause superficial and mucosal infections, to potentially fatal systemic or invasive infections in humans. These infections are more common in immunocompromised or critically ill patients and have a significant morbidity and fatality rate. Fungal pathogens utilize several strategies to adapt the host environment resulting in efficient and comprehensive alterations in their cellular metabolism. Fungal virulence is regulated by several factors and post-transcriptional regulation mechanisms involving mRNA molecules are one of them. Post-transcriptional controls have emerged as critical regulatory mechanisms involved in the pathogenesis of fungal species. The untranslated upstream and downstream regions of the mRNA, as well as RNA-binding proteins, regulate morphogenesis and virulence by controlling mRNA degradation and stability. The limited number of available therapeutic drugs, the emergence of multidrug resistance, and high death rates associated with systemic fungal illnesses pose a serious risk to human health. Therefore, new antifungal treatments that specifically target mRNA pathway components can decrease fungal pathogenicity and when combined increase the effectiveness of currently available antifungal drugs. This review summarizes the mRNA degradation pathways and their role in fungal pathogenesis.
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Affiliation(s)
- Zulikha Firdous
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, VPO-Ghudda, Bathinda 151401, India
| | - Sapna Kalra
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, VPO-Ghudda, Bathinda 151401, India
| | - Rituja Chattopadhyay
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, VPO-Ghudda, Bathinda 151401, India
| | - Vinay Kumar Bari
- Department of Biochemistry, School of Basic Sciences, Central University of Punjab, VPO-Ghudda, Bathinda 151401, India.
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2
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Saha U, Gaine R, Paira S, Das S, Das B. RRM1 and PAB domains of translation initiation factor eIF4G (Tif4631p) play a crucial role in the nuclear degradation of export-defective mRNAs in Saccharomyces cerevisiae. FEBS J 2024; 291:897-926. [PMID: 37994298 DOI: 10.1111/febs.17016] [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: 03/07/2023] [Revised: 10/02/2023] [Accepted: 11/21/2023] [Indexed: 11/24/2023]
Abstract
In Saccharomyces cerevisiae, the CBC-Tif4631p-dependent exosomal targeting (CTEXT) complex consisting of Cbc1/2p, Tif4631p and Upf3p promotes the exosomal degradation of aberrantly long 3'-extended, export-defective transcripts and a small group of normal (termed 'special') mRNAs. We carried out a systematic analysis of all previously characterized functional domains of the major CTEXT component Tif4631p by deleting each of them and interrogating their involvement in the nuclear surveillance of abnormally long 3'-extended and export-defective messages. Our analyses show that the N-terminal RNA recognition motif 1 (RRM1) and poly(A)-binding protein (PAB) domains of Tif4631p, spanning amino acid residues, 1-82 and 188-299 in its primary structure, respectively, play a crucial role in degrading these aberrant messages. Furthermore, the physical association of the nuclear exosome with the altered/variant CTEXT complex harboring any of the mutant Tif4631p proteins lacking either the RRM1 or PAB domain becomes abolished. This finding indicates that the association between CTEXT and the exosome is accomplished via interaction between these Tif4631p domains with the major exosome component, Rrp6p. Abolition of interaction between altered CTEXT (harboring any of the RRM1/PAB-deleted versions of Tif4631p) and the exosome further leads to the impaired recruitment of the RNA targets to the Rrp6p subunit of the exosome carried out by the RRM1/PAB domains of Tif4631p. When analyzing the Tif4631p-interacting proteins, we identified a DEAD-box RNA helicase (Dbp2p), as an interacting partner that turned out to be a previously unknown component of CTEXT. The present study provides a more complete description of the CTEXT complex and offers insight into the functional relationship of this complex with the nuclear exosome.
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Grants
- BT/PR27917/BRB/10/1673/2018 Department of Biotechnology, Ministry of Science and Technology, India
- BT/PR6078/BRB/10/1114/2012 Department of Biotechnology, Ministry of Science and Technology, India
- 38/1427/16/EMR-II Council of Scientific and Industrial Research, India
- 38/1280/11/EMR-II Council of Scientific and Industrial Research, India
- SR/SO/BB/0066/2012 Department of Science and Technology, Ministry of Science and Technology, India
- Department of Science & Technology and Biotechnology, Government of West Bengal
- SR/WOS-A/LS-1067/2014 Department of Science and Technology, India, WOS-A
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Affiliation(s)
- Upasana Saha
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Rajlaxmi Gaine
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Sunirmal Paira
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Satarupa Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Biswadip Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
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3
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Batista M, Langendijk-Genevaux P, Kwapisz M, Canal I, Phung DK, Plassart L, Capeyrou R, Moalic Y, Jebbar M, Flament D, Fichant G, Bouvier M, Clouet-d'Orval B. Evolutionary and functional insights into the Ski2-like helicase family in Archaea: a comparison of Thermococcales ASH-Ski2 and Hel308 activities. NAR Genom Bioinform 2024; 6:lqae026. [PMID: 38500564 PMCID: PMC10946056 DOI: 10.1093/nargab/lqae026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 02/19/2024] [Accepted: 02/27/2024] [Indexed: 03/20/2024] Open
Abstract
RNA helicases perform essential housekeeping and regulatory functions in all domains of life by binding and unwinding RNA molecules. The Ski2-like proteins are primordial helicases that play an active role in eukaryotic RNA homeostasis pathways, with multiple homologs having specialized functions. The significance of the expansion and diversity of Ski2-like proteins in Archaea, the third domain of life, has not yet been established. Here, by studying the phylogenetic diversity of Ski2-like helicases among archaeal genomes and the enzymatic activities of those in Thermococcales, we provide further evidence of the function of this protein family in archaeal metabolism of nucleic acids. We show that, in the course of evolution, ASH-Ski2 and Hel308-Ski2, the two main groups of Ski2-like proteins, have diverged in their biological functions. Whereas Hel308 has been shown to mainly act on DNA, we show that ASH-Ski2, previously described to be associated with the 5'-3' aRNase J exonuclease, acts on RNA by supporting an efficient annealing activity, but also an RNA unwinding with a 3'-5' polarity. To gain insights into the function of Ski2, we also analyse the transcriptome of Thermococcus barophilus ΔASH-Ski2 mutant strain and provide evidence of the importance of ASH-Ski2 in cellular metabolism pathways related to translation.
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Affiliation(s)
- Manon Batista
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | | | - Marta Kwapisz
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Isabelle Canal
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Duy Khanh Phung
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Laura Plassart
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Régine Capeyrou
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Yann Moalic
- Univ Brest, CNRS, Ifremer, UMR6197 Biologie et Ecologie des Ecosystèmes marins Profonds, F-29280 Plouzané, France
| | - Mohamed Jebbar
- Univ Brest, CNRS, Ifremer, UMR6197 Biologie et Ecologie des Ecosystèmes marins Profonds, F-29280 Plouzané, France
| | - Didier Flament
- Univ Brest, CNRS, Ifremer, UMR6197 Biologie et Ecologie des Ecosystèmes marins Profonds, F-29280 Plouzané, France
| | - Gwennaele Fichant
- LMGM, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Marie Bouvier
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
| | - Béatrice Clouet-d'Orval
- MCD, Centre de Biologie Intégrative (CBI), CNRS, Université de Toulouse, UT3, Toulouse, France
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4
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Chen L, Weir JR. The molecular machinery of meiotic recombination. Biochem Soc Trans 2024; 52:379-393. [PMID: 38348856 PMCID: PMC10903461 DOI: 10.1042/bst20230712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/15/2024] [Accepted: 01/16/2024] [Indexed: 02/29/2024]
Abstract
Meiotic recombination, a cornerstone of eukaryotic diversity and individual genetic identity, is essential for the creation of physical linkages between homologous chromosomes, facilitating their faithful segregation during meiosis I. This process requires that germ cells generate controlled DNA lesions within their own genome that are subsequently repaired in a specialised manner. Repair of these DNA breaks involves the modulation of existing homologous recombination repair pathways to generate crossovers between homologous chromosomes. Decades of genetic and cytological studies have identified a multitude of factors that are involved in meiotic recombination. Recent work has started to provide additional mechanistic insights into how these factors interact with one another, with DNA, and provide the molecular outcomes required for a successful meiosis. Here, we provide a review of the recent developments with a focus on protein structures and protein-protein interactions.
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Affiliation(s)
- Linda Chen
- Structural Biochemistry of Meiosis Group, Friedrich Miescher Laboratory, Max-Planck-Ring 9, 72076 Tübingen, Germany
| | - John R Weir
- Structural Biochemistry of Meiosis Group, Friedrich Miescher Laboratory, Max-Planck-Ring 9, 72076 Tübingen, Germany
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5
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Lee KY, Bremner R, Hartley J, Protheroe S, Haller W, Johnson T, Whyte L. Long term outcomes in children with trichohepatoenteric syndrome. Am J Med Genet A 2024; 194:141-149. [PMID: 37753667 DOI: 10.1002/ajmg.a.63409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Revised: 08/25/2023] [Accepted: 09/08/2023] [Indexed: 09/28/2023]
Abstract
Trichohepatoenteric syndrome (THES) is a rare autosomal recessive disorder caused by mutations in either TTC37 or SKIV2L, usually leading to congenital diarrhea as part of a multisystem disease. Here, we report on the natural history of the disease for the largest UK cohort of patients with THES from 1996 to 2020. We systematically reviewed the clinical records and pathological specimens of patients diagnosed with THES managed in a single tertiary pediatric gastroenterology unit. Between 1996 and 2020, 13 patients (7 female and 6 male) were diagnosed with THES either by mutation analysis or by clinical phenotype. Two patients died from complications of infection. All patients received parenteral nutrition (PN) of which six patients were weaned off PN. All patients had gastrointestinal tract inflammation on endoscopy. Almost half of the cohort were diagnosed with monogenic inflammatory bowel disease (IBD) by the age of 11 years, confirmed by endoscopic and histological findings. Protracted diarrhea causing intestinal failure improves with time in all patients with THES, but monogenic IBD develops in later childhood that is refractory to conventional IBD treatments. Respiratory issues contribute to significant morbidity and mortality, and good respiratory care is crucial to prevent comorbidity.
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Affiliation(s)
- Kwang Yang Lee
- Department of Paediatric Gastroenterology and Nutrition, Birmingham Children's Hospital, Birmingham, UK
- Department of Paediatric Gastroenterology and Nutrition, Bristol Royal Hospital for Children, Bristol, UK
| | - Ronald Bremner
- Department of Paediatric Gastroenterology and Nutrition, Birmingham Children's Hospital, Birmingham, UK
| | - Jane Hartley
- Liver Unit, Birmingham Children's Hospital, Birmingham, UK
| | - Sue Protheroe
- Department of Paediatric Gastroenterology and Nutrition, Birmingham Children's Hospital, Birmingham, UK
| | - Wolfram Haller
- Department of Paediatric Gastroenterology and Nutrition, Birmingham Children's Hospital, Birmingham, UK
- Institute of Clinical Sciences, University of Birmingham, Birmingham, UK
| | - Tracey Johnson
- Department of Nutrition and Dietetics, Birmingham Children's Hospital, Birmingham, UK
| | - Lisa Whyte
- Department of Paediatric Gastroenterology and Nutrition, Birmingham Children's Hospital, Birmingham, UK
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6
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Strawn G, Wong RWK, Young BP, Davey M, Nislow C, Conibear E, Loewen CJR, Mayor T. Genome-wide screen identifies new set of genes for improved heterologous laccase expression in Saccharomyces cerevisiae. Microb Cell Fact 2024; 23:36. [PMID: 38287338 PMCID: PMC10823697 DOI: 10.1186/s12934-024-02298-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 01/04/2024] [Indexed: 01/31/2024] Open
Abstract
The yeast Saccharomyces cerevisiae is widely used as a host cell for recombinant protein production due to its fast growth, cost-effective culturing, and ability to secrete large and complex proteins. However, one major drawback is the relatively low yield of produced proteins compared to other host systems. To address this issue, we developed an overlay assay to screen the yeast knockout collection and identify mutants that enhance recombinant protein production, specifically focusing on the secretion of the Trametes trogii fungal laccase enzyme. Gene ontology analysis of these mutants revealed an enrichment of processes including vacuolar targeting, vesicle trafficking, proteolysis, and glycolipid metabolism. We confirmed that a significant portion of these mutants also showed increased activity of the secreted laccase when grown in liquid culture. Notably, we found that the combination of deletions of OCA6, a tyrosine phosphatase gene, along with PMT1 or PMT2, two genes encoding ER membrane protein-O-mannosyltransferases involved in ER quality control, and SKI3, which encode for a component of the SKI complex responsible for mRNA degradation, further increased secreted laccase activity. Conversely, we also identified over 200 gene deletions that resulted in decreased secreted laccase activity, including many genes that encode for mitochondrial proteins and components of the ER-associated degradation pathway. Intriguingly, the deletion of the ER DNAJ co-chaperone gene SCJ1 led to almost no secreted laccase activity. When we expressed SCJ1 from a low-copy plasmid, laccase secretion was restored. However, overexpression of SCJ1 had a detrimental effect, indicating that precise dosing of key chaperone proteins is crucial for optimal recombinant protein expression. This study offers potential strategies for enhancing the overall yield of recombinant proteins and provides new avenues for further research in optimizing protein production systems.
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Affiliation(s)
- Garrett Strawn
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Ryan W K Wong
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada
| | - Barry P Young
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Michael Davey
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Corey Nislow
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Elizabeth Conibear
- Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada
| | - Christopher J R Loewen
- Department of Cellular and Physiological Sciences, University of British Columbia, Vancouver, BC, Canada
| | - Thibault Mayor
- Department of Biochemistry and Molecular Biology, Michael Smith Laboratories, University of British Columbia, Vancouver, BC, Canada.
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7
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Aoi Y, Shilatifard A. Transcriptional elongation control in developmental gene expression, aging, and disease. Mol Cell 2023; 83:3972-3999. [PMID: 37922911 DOI: 10.1016/j.molcel.2023.10.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 09/23/2023] [Accepted: 10/11/2023] [Indexed: 11/07/2023]
Abstract
The elongation stage of transcription by RNA polymerase II (RNA Pol II) is central to the regulation of gene expression in response to developmental and environmental cues in metazoan. Dysregulated transcriptional elongation has been associated with developmental defects as well as disease and aging processes. Decades of genetic and biochemical studies have painstakingly identified and characterized an ensemble of factors that regulate RNA Pol II elongation. This review summarizes recent findings taking advantage of genetic engineering techniques that probe functions of elongation factors in vivo. We propose a revised model of elongation control in this accelerating field by reconciling contradictory results from the earlier biochemical evidence and the recent in vivo studies. We discuss how elongation factors regulate promoter-proximal RNA Pol II pause release, transcriptional elongation rate and processivity, RNA Pol II stability and RNA processing, and how perturbation of these processes is associated with developmental disorders, neurodegenerative disease, cancer, and aging.
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Affiliation(s)
- Yuki Aoi
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Ali Shilatifard
- Simpson Querrey Institute for Epigenetics, Department of Biochemistry and Molecular Genetics Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
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8
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Keidel A, Kögel A, Reichelt P, Kowalinski E, Schäfer IB, Conti E. Concerted structural rearrangements enable RNA channeling into the cytoplasmic Ski238-Ski7-exosome assembly. Mol Cell 2023; 83:4093-4105.e7. [PMID: 37879335 PMCID: PMC10659929 DOI: 10.1016/j.molcel.2023.09.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/25/2023] [Accepted: 09/29/2023] [Indexed: 10/27/2023]
Abstract
The Ski2-Ski3-Ski8 (Ski238) helicase complex directs cytoplasmic mRNAs toward the nucleolytic exosome complex for degradation. In yeast, the interaction between Ski238 and exosome requires the adaptor protein Ski7. We determined different cryo-EM structures of the Ski238 complex depicting the transition from a rigid autoinhibited closed conformation to a flexible active open conformation in which the Ski2 helicase module has detached from the rest of Ski238. The open conformation favors the interaction of the Ski3 subunit with exosome-bound Ski7, leading to the recruitment of the exosome. In the Ski238-Ski7-exosome holocomplex, the Ski2 helicase module binds the exosome cap, enabling the RNA to traverse from the helicase through the internal exosome channel to the Rrp44 exoribonuclease. Our study pinpoints how conformational changes within the Ski238 complex regulate exosome recruitment for RNA degradation. We also reveal the remarkable conservation of helicase-exosome RNA channeling mechanisms throughout eukaryotic nuclear and cytoplasmic exosome complexes.
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Affiliation(s)
- Achim Keidel
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Alexander Kögel
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Peter Reichelt
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Eva Kowalinski
- EMBL Grenoble, 71 Avenue des Martyrs, 38072 Grenoble, France
| | - Ingmar B Schäfer
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany
| | - Elena Conti
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, Martinsried, 82152 Munich, Germany.
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9
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Alagar Boopathy LR, Beadle E, Garcia-Bueno Rico A, Vera M. Proteostasis regulation through ribosome quality control and no-go-decay. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1809. [PMID: 37488089 DOI: 10.1002/wrna.1809] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 06/14/2023] [Accepted: 06/30/2023] [Indexed: 07/26/2023]
Abstract
Cell functionality relies on the existing pool of proteins and their folding into functional conformations. This is achieved through the regulation of protein synthesis, which requires error-free mRNAs and ribosomes. Ribosomes are quality control hubs for mRNAs and proteins. Problems during translation elongation slow down the decoding rate, leading to ribosome halting and the eventual collision with the next ribosome. Collided ribosomes form a specific disome structure recognized and solved by ribosome quality control (RQC) mechanisms. RQC pathways orchestrate the degradation of the problematic mRNA by no-go decay and the truncated nascent peptide, the repression of translation initiation, and the recycling of the stalled ribosomes. All these events maintain protein homeostasis and return valuable ribosomes to translation. As such, cell homeostasis and function are maintained at the mRNA level by preventing the production of aberrant or unnecessary proteins. It is becoming evident that the crosstalk between RQC and the protein homeostasis network is vital for cell function, as the absence of RQC components leads to the activation of stress response and neurodegenerative diseases. Here, we review the molecular events of RQC discovered through well-designed stalling reporters. Given the impact of RQC in proteostasis, we discuss the relevance of identifying endogenous mRNA regulated by RQC and their preservation in stress conditions. This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms Translation > Regulation.
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Affiliation(s)
| | - Emma Beadle
- Department of Biochemistry, McGill University, Montreal, Canada
| | | | - Maria Vera
- Department of Biochemistry, McGill University, Montreal, Canada
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10
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Tomecki R, Drazkowska K, Kobylecki K, Tudek A. SKI complex: A multifaceted cytoplasmic RNA exosome cofactor in mRNA metabolism with links to disease, developmental processes, and antiviral responses. WILEY INTERDISCIPLINARY REVIEWS. RNA 2023; 14:e1795. [PMID: 37384835 DOI: 10.1002/wrna.1795] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Revised: 04/26/2023] [Accepted: 05/01/2023] [Indexed: 07/01/2023]
Abstract
RNA stability and quality control are integral parts of gene expression regulation. A key factor shaping eukaryotic transcriptomes, mainly via 3'-5' exoribonucleolytic trimming or degradation of diverse transcripts in nuclear and cytoplasmic compartments, is the RNA exosome. Precise exosome targeting to various RNA molecules requires strict collaboration with specialized auxiliary factors, which facilitate interactions with its substrates. The predominant class of cytoplasmic RNA targeted by the exosome are protein-coding transcripts, which are carefully scrutinized for errors during translation. Normal, functional mRNAs are turned over following protein synthesis by the exosome or by Xrn1 5'-3'-exonuclease, acting in concert with Dcp1/2 decapping complex. In turn, aberrant transcripts are eliminated by dedicated surveillance pathways, triggered whenever ribosome translocation is impaired. Cytoplasmic 3'-5' mRNA decay and surveillance are dependent on the tight cooperation between the exosome and its evolutionary conserved co-factor-the SKI (superkiller) complex (SKIc). Here, we summarize recent findings from structural, biochemical, and functional studies of SKIc roles in controlling cytoplasmic RNA metabolism, including links to various cellular processes. Mechanism of SKIc action is illuminated by presentation of its spatial structure and details of its interactions with exosome and ribosome. Furthermore, contribution of SKIc and exosome to various mRNA decay pathways, usually converging on recycling of ribosomal subunits, is delineated. A crucial physiological role of SKIc is emphasized by describing association between its dysfunction and devastating human disease-a trichohepatoenteric syndrome (THES). Eventually, we discuss SKIc functions in the regulation of antiviral defense systems, cell signaling and developmental transitions, emerging from interdisciplinary investigations. This article is categorized under: RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Turnover and Surveillance > Regulation of RNA Stability RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes.
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Affiliation(s)
- Rafal Tomecki
- Laboratory of RNA Processing and Decay, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
- Institute of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, Warsaw, Poland
| | - Karolina Drazkowska
- Laboratory of Epitranscriptomics, Department of Environmental Microbiology and Biotechnology, Institute of Microbiology, Faculty of Biology, Biological and Chemical Research Centre, University of Warsaw, Warsaw, Poland
| | - Kamil Kobylecki
- Laboratory of RNA Processing and Decay, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
| | - Agnieszka Tudek
- Laboratory of RNA Processing and Decay, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Warsaw, Poland
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11
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Yu Y, Wang J, Liu K, Zheng Z, Arter M, Bouuaert CC, Pu S, Patel DJ, Keeney S. Cryo-EM structure of the Spo11 core complex bound to DNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.31.564985. [PMID: 37961437 PMCID: PMC10634984 DOI: 10.1101/2023.10.31.564985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The DNA double-strand breaks that initiate meiotic recombination are formed by topoisomerase relative Spo11, supported by conserved auxiliary factors. Because high-resolution structural data are lacking, many questions remain about the architecture of Spo11 and its partners and how they engage with DNA. We report cryo-EM structures at up to 3.3 Å resolution of DNA-bound core complexes of Saccharomyces cerevisiae Spo11 with Rec102, Rec104, and Ski8. In these structures, monomeric core complexes make extensive contacts with the DNA backbone and with the recessed 3'-OH and first 5' overhanging nucleotide, definitively establishing the molecular determinants of DNA end-binding specificity and providing insight into DNA cleavage preferences in vivo. The structures of individual subunits and their interfaces, supported by functional data in yeast, provide insight into the role of metal ions in DNA binding and uncover unexpected structural variation in homologs of the Top6BL component of the core complex.
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Affiliation(s)
- You Yu
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Juncheng Wang
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Kaixian Liu
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Zhi Zheng
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Louis V. Gerstner Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Meret Arter
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Corentin Claeys Bouuaert
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Howard Hughes Medical Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Stephen Pu
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Howard Hughes Medical Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Dinshaw J. Patel
- Structural Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Louis V. Gerstner Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, NY 10065
| | - Scott Keeney
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Louis V. Gerstner Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, NY 10065
- Howard Hughes Medical Institute, Memorial Sloan Kettering Cancer Center, New York, NY 10065
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12
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Krempl C, Lazzaretti D, Sprangers R. A structural biology view on the enzymes involved in eukaryotic mRNA turnover. Biol Chem 2023; 404:1101-1121. [PMID: 37709756 DOI: 10.1515/hsz-2023-0182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 08/24/2023] [Indexed: 09/16/2023]
Abstract
The cellular environment contains numerous ribonucleases that are dedicated to process mRNA transcripts that have been targeted for degradation. Here, we review the three dimensional structures of the ribonuclease complexes (Pan2-Pan3, Ccr4-Not, Xrn1, exosome) and the mRNA decapping enzymes (Dcp2, DcpS) that are involved in mRNA turnover. Structures of major parts of these proteins have been experimentally determined. These enzymes and factors do not act in isolation, but are embedded in interaction networks which regulate enzyme activity and ensure that the appropriate substrates are recruited. The structural details of the higher order complexes that form can, in part, be accurately deduced from known structural data of sub-complexes. Interestingly, many of the ribonuclease and decapping enzymes have been observed in structurally different conformations. Together with experimental data, this highlights that structural changes are often important for enzyme function. We conclude that the known structural data of mRNA decay factors provide important functional insights, but that static structural data needs to be complemented with information regarding protein motions to complete the picture of how transcripts are turned over. In addition, we highlight multiple aspects that influence mRNA turnover rates, but that have not been structurally characterized so far.
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Affiliation(s)
- Christina Krempl
- Institute of Biophysics and Physical Biochemistry, Regensburg Center for Biochemistry, University of Regensburg, D-93053 Regensburg, Germany
| | - Daniela Lazzaretti
- Institute of Biophysics and Physical Biochemistry, Regensburg Center for Biochemistry, University of Regensburg, D-93053 Regensburg, Germany
| | - Remco Sprangers
- Institute of Biophysics and Physical Biochemistry, Regensburg Center for Biochemistry, University of Regensburg, D-93053 Regensburg, Germany
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13
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Paira S, Chakraborty A, Das B. The Sequential Recruitments of Rab-GTPase Ypt1p and the NNS Complex onto pre- HAC1 mRNA Promote Its Nuclear Degradation in Baker's Yeast. Mol Cell Biol 2023; 43:371-400. [PMID: 37533322 PMCID: PMC10448977 DOI: 10.1080/10985549.2023.2227016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 06/10/2023] [Accepted: 06/12/2023] [Indexed: 08/04/2023] Open
Abstract
Induction of unfolded protein response involves activation of transcription factor Hac1p that is encoded by HAC1 pre-mRNA harboring an intron and a bipartite element (BE), which is subjected to nuclear mRNA decay by the nuclear exosome/Cbc1p-Tif4631p-dependent Exosome Targeting (CTEXT) complex. Using a combination of genetic and biochemical approaches, we demonstrate that a Rab-GTPase Ypt1p controls unfolded protein response signaling dynamics. This regulation relies on the nuclear localization of a small fraction of the cellular Ypt1p pool in the absence of endoplasmic reticulum (ER)-stress causing a strong association of the nuclear Ypt1p with pre-HAC1 mRNA that eventually promotes sequential recruitments of NNS, CTEXT, and the nuclear exosome onto this pre-mRNA. Recruitment of these decay factors onto pre-HAC1 mRNA is accompanied by its rapid nuclear decay that produces a precursor RNA pool lacking functional BE thereby causing its inefficient targeting to Ire1p foci leading to their diminished splicing and translation. ER stress triggers rapid relocalization of the nuclear pool of Ypt1p to the cytoplasm leading to its dissociation from pre-HAC1 mRNA thereby causing decreased recruitment of these decay factors to precursor HAC1 RNA leading to its diminished degradation. Reduced decay results in an increased abundance of pre-HAC1 mRNA with intact functional BE leading to its enhanced recruitment to Ire1p foci.
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Affiliation(s)
- Sunirmal Paira
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Anish Chakraborty
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
| | - Biswadip Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata, India
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14
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Ge L, Cao B, Qiao R, Cui H, Li S, Shan H, Gong P, Zhang M, Li H, Wang A, Zhou X, Li F. SUMOylation-modified Pelota-Hbs1 RNA surveillance complex restricts the infection of potyvirids in plants. MOLECULAR PLANT 2023; 16:632-642. [PMID: 36597359 DOI: 10.1016/j.molp.2022.12.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 12/12/2022] [Accepted: 12/31/2022] [Indexed: 06/17/2023]
Abstract
RNA quality control nonsense-mediated decay is involved in viral restriction in both plants and animals. However, it is not known whether two other RNA quality control pathways, nonstop decay and no-go decay, are capable of restricting viruses in plants. Here, we show that the evolutionarily conserved Pelota-Hbs1 complex negatively regulates infection of plant viruses in the family Potyviridae (termed potyvirids), the largest group of plant RNA viruses that accounts for more than half of the viral crop damage worldwide. Pelota enables the recognition of the functional G1-2A6-7 motif in the P3 cistron, which is conserved in almost all potyvirids. This allows Pelota to target the virus and act as a viral restriction factor. Furthermore, Pelota interacts with the SUMO E2-conjugating enzyme SCE1 and is SUMOylated in planta. Blocking Pelota SUMOylation disrupts the ability to recruit Hbs1 and inhibits viral RNA degradation. These findings reveal the functional importance of Pelota SUMOylation during the infection of potyvirids in plants.
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Affiliation(s)
- Linhao Ge
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Buwei Cao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Rui Qiao
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongguang Cui
- Key Laboratory of Green Prevention and Control of Tropical Plant Diseases and Pests, Ministry of Education and College of Plant Protection, Hainan University, Haikou, Hainan, China
| | - Shaofang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hongying Shan
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Pan Gong
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Mingzhen Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Hao Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON, Canada; Department of Biology, Western University, London, ON, Canada
| | - Xueping Zhou
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China; State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, Zhejiang, China.
| | - Fangfang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.
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15
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Moreno Traspas R, Teoh TS, Wong PM, Maier M, Chia CY, Lay K, Ali NA, Larson A, Al Mutairi F, Al-Sannaa NA, Faqeih EA, Alfadhel M, Cheema HA, Dupont J, Bézieau S, Isidor B, Low DY, Wang Y, Tan G, Lai PS, Piloquet H, Joubert M, Kayserili H, Kripps KA, Nahas SA, Wartchow EP, Warren M, Bhavani GS, Dasouki M, Sandoval R, Carvalho E, Ramos L, Porta G, Wu B, Lashkari HP, AlSaleem B, BaAbbad RM, Abreu Ferrão AN, Karageorgou V, Ordonez-Herrera N, Khan S, Bauer P, Cogne B, Bertoli-Avella AM, Vincent M, Girisha KM, Reversade B. Loss of FOCAD, operating via the SKI messenger RNA surveillance pathway, causes a pediatric syndrome with liver cirrhosis. Nat Genet 2022; 54:1214-1226. [PMID: 35864190 PMCID: PMC7615854 DOI: 10.1038/s41588-022-01120-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Accepted: 06/02/2022] [Indexed: 02/08/2023]
Abstract
Cirrhosis is usually a late-onset and life-threatening disease characterized by fibrotic scarring and inflammation that disrupts liver architecture and function. While it is typically the result of alcoholism or hepatitis viral infection in adults, its etiology in infants is much less understood. In this study, we report 14 children from ten unrelated families presenting with a syndromic form of pediatric liver cirrhosis. By genome/exome sequencing, we found recessive variants in FOCAD segregating with the disease. Zebrafish lacking focad phenocopied the human disease, revealing a signature of altered messenger RNA (mRNA) degradation processes in the liver. Using patient's primary cells and CRISPR-Cas9-mediated inactivation in human hepatic cell lines, we found that FOCAD deficiency compromises the SKI mRNA surveillance pathway by reducing the levels of the RNA helicase SKIC2 and its cofactor SKIC3. FOCAD knockout hepatocytes exhibited lowered albumin expression and signs of persistent injury accompanied by CCL2 overproduction. Our results reveal the importance of FOCAD in maintaining liver homeostasis and disclose a possible therapeutic intervention point via inhibition of the CCL2/CCR2 signaling axis.
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Affiliation(s)
- Ricardo Moreno Traspas
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore.
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
| | - Tze Shin Teoh
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Pui-Mun Wong
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Michael Maier
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Crystal Y Chia
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Kenneth Lay
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Nur Ain Ali
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore
| | - Austin Larson
- Section of Pediatrics-Clinical Genetics and Metabolism, Children's Hospital Colorado, Aurora, CO, USA
| | - Fuad Al Mutairi
- Department of Genetics and Precision Medicine, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- College of Medicine, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | | | - Eissa Ali Faqeih
- Section of Medical Genetics, Children's Specialist Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Majid Alfadhel
- Department of Genetics and Precision Medicine, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- Department of Medical Genomic Research, King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Huma Arshad Cheema
- Division of Pediatric Gastroenterology-Hepatology and Nutrition, The Children's Hospital and The Institute of Child Health, Lahore, Pakistan
| | - Juliette Dupont
- Department of Pediatrics, Genetic Services, Lisbon North University Hospital Center, Lisbon, Portugal
| | - Stéphane Bézieau
- Medical Genetics Service, Nantes University Hospital Center, Nantes, France
| | - Bertrand Isidor
- Medical Genetics Service, Nantes University Hospital Center, Nantes, France
| | - Dorrain Yanwen Low
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Yulan Wang
- Singapore Phenome Center, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Grace Tan
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Poh San Lai
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Hugues Piloquet
- Gastropediatrics Department, Nantes University Hospital Center, Nantes, France
| | - Madeleine Joubert
- Anatomopathology Department, Nantes University Hospital Center, Nantes, France
| | - Hulya Kayserili
- Medical Genetics Department, School of Medicine, Koç University, Istanbul, Turkey
| | - Kimberly A Kripps
- Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, OR, USA
| | - Shareef A Nahas
- Rady Children's Institute for Genomic Medicine, San Diego, CA, USA
| | - Eric P Wartchow
- Department of Pathology and Laboratory Medicine, Children's Hospital Colorado, Aurora, CO, USA
| | - Mikako Warren
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Gandham SriLakshmi Bhavani
- Department of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, India
| | - Majed Dasouki
- Department of Pediatric Genetics, AdventHealth Medical Group, Orlando, FL, USA
| | - Renata Sandoval
- Department of Oncogenetics, Hospital Sírio-Libanês, Brasília, Brazil
| | - Elisa Carvalho
- Department of Pediatric Gastroenterology and Hepatology, Hospital da Criança de Brasília José Alencar, UniCEUB, Brasília, Brazil
| | - Luiza Ramos
- Mendelics Genomic Analysis, São Paulo, Brazil
| | - Gilda Porta
- Department of Pediatric Hepatology, Transplant Unit, Hospital Sírio-Libanês, São Paulo, Brazil
| | - Bin Wu
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
- Institute of Structural Biology, Nanyang Technological University, Singapore, Singapore
| | - Harsha Prasada Lashkari
- Department of Pediatrics, Kasturba Medical College, Mangalore, India
- Manipal Academy of Higher Education, Manipal, India
| | - Badr AlSaleem
- Section of Pediatric Gastroenterology-Hepatology, Children's Specialist Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Raeda M BaAbbad
- Section of Pediatric Gastroenterology-Hepatology, Children's Specialist Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | | | | | | | | | | | - Benjamin Cogne
- Medical Genetics Service, Nantes University Hospital Center, Nantes, France
| | | | - Marie Vincent
- Medical Genetics Service, Nantes University Hospital Center, Nantes, France
| | - Katta Mohan Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, India
| | - Bruno Reversade
- Laboratory of Human Genetics and Therapeutics, Genome Institute of Singapore, A*STAR, Singapore, Singapore.
- Department of Pediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.
- Medical Genetics Department, School of Medicine, Koç University, Istanbul, Turkey.
- Institute of Molecular and Cell Biology, A*STAR, Singapore, Singapore.
- Smart-Health Initiative, Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology (KAUST), Thuwal, Saudi Arabia.
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16
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Yang K, Han J, Gill JG, Park JY, Sathe MN, Gattineni J, Wright T, Wysocki C, de la Morena MT, Yan N. The mammalian SKIV2L RNA exosome is essential for early B cell development. Sci Immunol 2022; 7:eabn2888. [PMID: 35658009 PMCID: PMC9376044 DOI: 10.1126/sciimmunol.abn2888] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The SKIV2L RNA exosome is an evolutionarily conserved RNA degradation complex in the eukaryotes. Mutations in the SKIV2L gene are associated with a severe inherited disorder, trichohepatoenteric syndrome (THES), with multisystem involvement but unknown disease mechanism. Here, we reported a THES patient with SKIV2L mutations showing severe primary B cell immunodeficiency, hypogammaglobulinemia, and kappa-restricted plasma cell dyscrasia but normal T cell and NK cell function. To corroborate these findings, we made B cell-specific Skiv2l knockout mice (Skiv2lfl/flCd79a-Cre), which lacked both conventional B-2 and innate-like B-1 B cells in the periphery and secondary lymphoid organs. This was linked to a requirement of SKIV2L RNA exosome activity in the bone marrow during early B cell development at the pro-B cell to large pre-B cell transition. Mechanistically, Skiv2l-deficient pro-B cells exhibited cell cycle arrest and DNA damage. Furthermore, loss of Skiv2l led to substantial out-of-frame V(D)J rearrangement of immunoglobulin heavy chain and severely reduced surface expression of μH, both of which are crucial for pre-BCR signaling and proliferative burst during early B cell development. Together, our data demonstrated a crucial role for SKIV2L RNA exosome in early B cell development in both human and mice by ensuring proper V(D)J recombination and Igh expression, which serves as the molecular basis for immunodeficiency associated with THES.
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Affiliation(s)
- Kun Yang
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jie Han
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jennifer G. Gill
- Department of Dermatology, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jason Y. Park
- Department of Pathology and the Eugene McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, USA
| | - Meghana N. Sathe
- Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Jyothsna Gattineni
- Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Tracey Wright
- Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA
| | - Christian Wysocki
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, TX, USA
| | - M. Teresa de la Morena
- Department of Pediatrics, University of Washington, Seattle, WA, USA
- Seattle Children's Hospital, Seattle, WA, USA
| | - Nan Yan
- Department of Immunology, UT Southwestern Medical Center, Dallas, TX, USA
- Department of Microbiology, UT Southwestern Medical Center, Dallas, TX, USA
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17
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Orlando LJ, Yim MK, Hallmark T, Cotner M, Johnson SJ, van Hoof A. A yeast model for trichohepatoenteric syndrome suggests strong loss of Ski2 function in most causative mutations. MICROPUBLICATION BIOLOGY 2022; 2022:10.17912/micropub.biology.000575. [PMID: 35607352 PMCID: PMC9123431 DOI: 10.17912/micropub.biology.000575] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 05/13/2022] [Accepted: 05/19/2022] [Indexed: 12/01/2022]
Abstract
The intestinal and immune disorder trichohepatoenteric syndrome (THES) is characterized by mutations in human Ski2 and Ski3, also known as SKIV2L and TTC37, respectively. The mechanism by which these mutations leads to the immunodeficiency, chronic diarrhea, failure to thrive and liver disease associated with THES is unknown. To what degree THES patient mutations in Ski2 affect Ski2 function and how the differences in Ski2 function could lead to varying patient outcomes has not been studied. Here, we assayed function of THES ski2 mutants in the yeast homolog. Our results show that most THES patient mutations cause severe dysfunction in Ski2. This provides the first functional analysis of these mutations and suggests that the yeast assay may be helpful in distinguishing between pathological and benign variants.
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Affiliation(s)
- Luisa J Orlando
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston and The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston
| | - Matthew K Yim
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Thomson Hallmark
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Michael Cotner
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Sean J Johnson
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah
| | - Ambro van Hoof
- Department of Microbiology and Molecular Genetics, The University of Texas Health Science Center at Houston and The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston
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18
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Kögel A, Keidel A, Bonneau F, Schäfer IB, Conti E. The human SKI complex regulates channeling of ribosome-bound RNA to the exosome via an intrinsic gatekeeping mechanism. Mol Cell 2022; 82:756-769.e8. [PMID: 35120588 PMCID: PMC8860381 DOI: 10.1016/j.molcel.2022.01.009] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/01/2021] [Accepted: 01/07/2022] [Indexed: 12/31/2022]
Abstract
The superkiller (SKI) complex is the cytoplasmic co-factor and regulator of the RNA-degrading exosome. In human cells, the SKI complex functions mainly in co-translational surveillance-decay pathways, and its malfunction is linked to a severe congenital disorder, the trichohepatoenteric syndrome. To obtain insights into the molecular mechanisms regulating the human SKI (hSKI) complex, we structurally characterized several of its functional states in the context of 80S ribosomes and substrate RNA. In a prehydrolytic ATP form, the hSKI complex exhibits a closed conformation with an inherent gating system that effectively traps the 80S-bound RNA into the hSKI2 helicase subunit. When active, hSKI switches to an open conformation in which the gating is released and the RNA 3′ end exits the helicase. The emerging picture is that the gatekeeping mechanism and architectural remodeling of hSKI underpin a regulated RNA channeling system that is mechanistically conserved among the cytoplasmic and nuclear helicase-exosome complexes. hSKI has closed and open states connected to different helicase conformations The intrinsic closed state traps the RNA 3′ end and blocks the RNA exit path ATP induces the open state of hSKI, allowing 80S ribosome-bound RNA extraction The hSKI open state primes hSKI2 for channeling RNA to the cytosolic exosome
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Affiliation(s)
- Alexander Kögel
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Munich, Germany
| | - Achim Keidel
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Munich, Germany
| | - Fabien Bonneau
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Munich, Germany
| | - Ingmar B Schäfer
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Munich, Germany.
| | - Elena Conti
- Department of Structural Cell Biology, Max Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Munich, Germany.
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19
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Yang K, Han J, Asada M, Gill JG, Park JY, Sathe MN, Gattineni J, Wright T, Wysocki CA, de la Morena MT, Garza LA, Yan N. Cytoplasmic RNA quality control failure engages mTORC1-mediated autoinflammatory disease. J Clin Invest 2022; 132:e146176. [PMID: 35040435 PMCID: PMC8759780 DOI: 10.1172/jci146176] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 10/27/2021] [Indexed: 12/23/2022] Open
Abstract
Inborn errors of nucleic acid metabolism often cause aberrant activation of nucleic acid sensing pathways, leading to autoimmune or autoinflammatory diseases. The SKIV2L RNA exosome is cytoplasmic RNA degradation machinery that was thought to be essential for preventing the self-RNA-mediated interferon (IFN) response. Here, we demonstrate the physiological function of SKIV2L in mammals. We found that Skiv2l deficiency in mice disrupted epidermal and T cell homeostasis in a cell-intrinsic manner independently of IFN. Skiv2l-deficient mice developed skin inflammation and hair abnormality, which were also observed in a SKIV2L-deficient patient. Epidermis-specific deletion of Skiv2l caused hyperproliferation of keratinocytes and disrupted epidermal stratification, leading to impaired skin barrier with no appreciable IFN activation. Moreover, Skiv2l-deficient T cells were chronically hyperactivated and these T cells attacked lesional skin as well as hair follicles. Mechanistically, SKIV2L loss activated the mTORC1 pathway in both keratinocytes and T cells. Both systemic and topical rapamycin treatment of Skiv2l-deficient mice ameliorated epidermal hyperplasia and skin inflammation. Together, we demonstrate that mTORC1, a classical nutrient sensor, also senses cytoplasmic RNA quality control failure and drives autoinflammatory disease. We also propose SKIV2L-associated trichohepatoenteric syndrome (THES) as a new mTORopathy for which sirolimus may be a promising therapy.
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Affiliation(s)
- Kun Yang
- Department of Immunology and
- Department of Microbiology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Jie Han
- Department of Immunology and
- Department of Microbiology, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Mayumi Asada
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | | | - Jason Y. Park
- Department of Pathology and the Eugene McDermott Center for Human Growth and Development
| | | | | | | | - Christian A. Wysocki
- Department of Internal Medicine, UT Southwestern Medical Center, Dallas, Texas, USA
| | - M. Teresa de la Morena
- Department of Pediatrics, University of Washington and
- Seattle Children’s Hospital, Seattle, Washington, USA
| | - Luis A. Garza
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Nan Yan
- Department of Immunology and
- Department of Microbiology, UT Southwestern Medical Center, Dallas, Texas, USA
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20
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Abstract
Loss-of-function mutations in SKIV2L underlie trichohepatoenteric syndrome (THES2), a rare inborn error of immunity characterized by diarrhea, skin lesions, brittle hair, and immunodeficiency. SKIV2L is part of a multiprotein complex required for exosome-mediated RNA surveillance through RNA decay. In this issue of the JCI, Yang et al. delineate a mechanism underlying autoinflammatory skin disease in Skiv2l-deficient mice. Thus, a lack of SKIV2L activates mTORC1 signaling in keratinocytes and T cells, impeding skin barrier integrity and T cell homeostasis. Interestingly, treatment with the mTOR inhibitor rapamycin improves skin symptoms in Skiv2l-deficient mice, suggesting a possible therapeutic avenue for patients with THES2.
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21
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Vigh ML, Bressendorff S, Thieffry A, Arribas-Hernández L, Brodersen P. Nuclear and cytoplasmic RNA exosomes and PELOTA1 prevent miRNA-induced secondary siRNA production in Arabidopsis. Nucleic Acids Res 2022; 50:1396-1415. [PMID: 35037064 PMCID: PMC8860578 DOI: 10.1093/nar/gkab1289] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 12/13/2021] [Accepted: 01/03/2022] [Indexed: 11/14/2022] Open
Abstract
Amplification of short interfering RNA (siRNAs) via RNA-dependent RNA polymerases (RdRPs) is of fundamental importance in RNA silencing. Plant microRNA (miRNA) action generally does not involve engagement of RdRPs, in part thanks to a poorly understood activity of the cytoplasmic exosome adaptor SKI2. Here, we show that inactivation of the exosome subunit RRP45B and SKI2 results in similar patterns of miRNA-induced siRNA production. Furthermore, loss of the nuclear exosome adaptor HEN2 leads to secondary siRNA production from miRNA targets largely distinct from those producing siRNAs in ski2. Importantly, mutation of the Release Factor paralogue PELOTA1 required for subunit dissociation of stalled ribosomes causes siRNA production from miRNA targets overlapping with, but distinct from, those affected in ski2 and rrp45b mutants. We also show that in exosome mutants, miRNA targets can be sorted into producers and non-producers of illicit secondary siRNAs based on trigger miRNA levels and miRNA:target affinity rather than on presence of 5′-cleavage fragments. We propose that stalled RNA-Induced Silencing Complex (RISC) and ribosomes, but not mRNA cleavage fragments released from RISC, trigger siRNA production, and that the exosome limits siRNA amplification by reducing RISC dwell time on miRNA target mRNAs while PELOTA1 does so by reducing ribosome stalling.
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Affiliation(s)
- Maria L Vigh
- University of Copenhagen, Copenhagen Plant Science Center, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Simon Bressendorff
- University of Copenhagen, Copenhagen Plant Science Center, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Axel Thieffry
- University of Copenhagen, Copenhagen Plant Science Center, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Laura Arribas-Hernández
- University of Copenhagen, Copenhagen Plant Science Center, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
| | - Peter Brodersen
- University of Copenhagen, Copenhagen Plant Science Center, Ole Maaløes Vej 5, 2200 Copenhagen N, Denmark
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22
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Humphreys IR, Pei J, Baek M, Krishnakumar A, Anishchenko I, Ovchinnikov S, Zhang J, Ness TJ, Banjade S, Bagde SR, Stancheva VG, Li XH, Liu K, Zheng Z, Barrero DJ, Roy U, Kuper J, Femández IS, Szakal B, Branzei D, Rizo J, Kisker C, Greene EC, Biggins S, Keeney S, Miller EA, Fromme JC, Hendrickson TL, Cong Q, Baker D. Computed structures of core eukaryotic protein complexes. Science 2021; 374:eabm4805. [PMID: 34762488 PMCID: PMC7612107 DOI: 10.1126/science.abm4805] [Citation(s) in RCA: 243] [Impact Index Per Article: 81.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Protein-protein interactions play critical roles in biology, but the structures of many eukaryotic protein complexes are unknown, and there are likely many interactions not yet identified. We take advantage of advances in proteome-wide amino acid coevolution analysis and deep-learning–based structure modeling to systematically identify and build accurate models of core eukaryotic protein complexes within the Saccharomyces cerevisiae proteome. We use a combination of RoseTTAFold and AlphaFold to screen through paired multiple sequence alignments for 8.3 million pairs of yeast proteins, identify 1505 likely to interact, and build structure models for 106 previously unidentified assemblies and 806 that have not been structurally characterized. These complexes, which have as many as five subunits, play roles in almost all key processes in eukaryotic cells and provide broad insights into biological function.
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Affiliation(s)
- Ian R. Humphreys
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Jimin Pei
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Minkyung Baek
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Aditya Krishnakumar
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Ivan Anishchenko
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
| | - Sergey Ovchinnikov
- Faculty of Arts and Sciences, Division of Science, Harvard University, Cambridge, MA, USA
- John Harvard Distinguished Science Fellowship Program, Harvard University, Cambridge, MA, USA
| | - Jing Zhang
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Travis J. Ness
- Department of Chemistry, Wayne State University, Detroit, MI, USA
| | - Sudeep Banjade
- Department of Molecular Biology & Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Saket R. Bagde
- Department of Molecular Biology & Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | | | - Xiao-Han Li
- MRC Laboratory of Molecular Biology, Cambridge, CB2 0QH, UK
| | - Kaixian Liu
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY
| | - Zhi Zheng
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, New York, NY
| | - Daniel J. Barrero
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Upasana Roy
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Jochen Kuper
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Israel S. Femández
- Department of Structural Biology, St Jude Children's Research Hospital, Memphis, TN, USA
| | - Barnabas Szakal
- IFOM, the FIRC Institute of Molecular Oncology, Via Adamello 16, 20139, Milan, Italy
| | - Dana Branzei
- IFOM, the FIRC Institute of Molecular Oncology, Via Adamello 16, 20139, Milan, Italy
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche (IGM-CNR), Via Abbiategrasso 207, 27100, Pavia, Italy
| | - Josep Rizo
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Caroline Kisker
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Eric C. Greene
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, USA
| | - Sue Biggins
- Howard Hughes Medical Institute, Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Scott Keeney
- Molecular Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY
- Gerstner Sloan Kettering Graduate School of Biomedical Sciences, New York, NY
- Howard Hughes Medical Institute, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | | | - J. Christopher Fromme
- Department of Molecular Biology & Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | | | - Qian Cong
- Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, Dallas, TX, USA
- Department of Biophysics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - David Baker
- Department of Biochemistry, University of Washington, Seattle, WA, USA
- Institute for Protein Design, University of Washington, Seattle, WA, USA
- Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
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23
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Chen YG, Hur S. Cellular origins of dsRNA, their recognition and consequences. Nat Rev Mol Cell Biol 2021; 23:286-301. [PMID: 34815573 DOI: 10.1038/s41580-021-00430-1] [Citation(s) in RCA: 114] [Impact Index Per Article: 38.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/12/2021] [Indexed: 01/02/2023]
Abstract
Double-stranded RNA (dsRNA) is associated with most viral infections - it either constitutes the viral genome (in the case of dsRNA viruses) or is generated in host cells during viral replication. Hence, nearly all organisms have the capability of recognizing dsRNA and mounting a response, the primary aim of which is to mitigate the potential infection. In vertebrates, a set of innate immune receptors for dsRNA induce a multitude of cell-intrinsic and cell-extrinsic immune responses upon dsRNA recognition. Notably, recent studies showed that vertebrate cells can accumulate self-derived dsRNAs or dsRNA-like species upon dysregulation of several cellular processes, activating the very same immune pathways as in infected cells. On the one hand, such aberrant immune activation in the absence of infection can lead to pathogenesis of immune disorders, such as Aicardi-Goutières syndrome. On the other hand, the same innate immune reaction can be induced in a controlled setting for a therapeutic benefit, as occurs in immunotherapies. In this Review, we describe mechanisms by which immunostimulatory dsRNAs are generated in mammalian cells, either by viruses or by the host cells, and how cells respond to them, with the focus on recent developments regarding the role of cellular dsRNAs in immune modulation.
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Affiliation(s)
- Y Grace Chen
- Department of Immunobiology, Yale University School of Medicine, New Haven, CT, USA.
| | - Sun Hur
- Harvard Medical School & Boston Children's Hospital, Boston, MA, USA.
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24
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Singh P, Chaudhuri A, Banerjea M, Marathe N, Das B. Nrd1p identifies aberrant and natural exosomal target messages during the nuclear mRNA surveillance in Saccharomyces cerevisiae. Nucleic Acids Res 2021; 49:11512-11536. [PMID: 34664673 PMCID: PMC8599857 DOI: 10.1093/nar/gkab930] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2021] [Accepted: 10/16/2021] [Indexed: 12/24/2022] Open
Abstract
Nuclear degradation of aberrant mRNAs in Saccharomyces cerevisiae is accomplished by the nuclear exosome and its cofactors TRAMP/CTEXT. Evidence from this investigation establishes a universal role of the Nrd1p-Nab3p-Sen1p (NNS) complex in the nuclear decay of all categories of aberrant mRNAs. In agreement with this, both nrd1-1 and nrd1-2 mutations impaired the decay of all classes of aberrant messages. This phenotype is similar to that displayed by GAL::RRP41 and rrp6-Δ mutant yeast strains. Remarkably, however, nrd1ΔCID mutation (lacking the C-terminal domain required for interaction of Nrd1p with RNAPII) only diminished the decay of aberrant messages with defects occurring during the early stage of mRNP biogenesis, without affecting other messages with defects generated later in the process. Co-transcriptional recruitment of Nrd1p on the aberrant mRNAs was vital for their concomitant decay. Strikingly, this recruitment on to mRNAs defective in the early phases of biogenesis is solely dependent upon RNAPII. In contrast, Nrd1p recruitment onto export-defective transcripts with defects occurring in the later stage of biogenesis is independent of RNAPII and dependent on the CF1A component, Pcf11p, which explains the observed characteristic phenotype of nrd1ΔCID mutation. Consistently, pcf11-2 mutation displayed a selective impairment in the degradation of only the export-defective messages.
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Affiliation(s)
- Pragyan Singh
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata - 700032, West Bengal, India
| | - Anusha Chaudhuri
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata - 700032, West Bengal, India
| | - Mayukh Banerjea
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata - 700032, West Bengal, India
| | - Neeraja Marathe
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata - 700032, West Bengal, India
| | - Biswadip Das
- Department of Life Science and Biotechnology, Jadavpur University, Kolkata - 700032, West Bengal, India
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25
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Hojka-Osinska A, Chlebowski A, Grochowska J, Owczarek EP, Affek K, Kłosowska-Kosicka K, Szczesny RJ, Dziembowski A. Landscape of functional interactions of human processive ribonucleases revealed by high-throughput siRNA screenings. iScience 2021; 24:103036. [PMID: 34541468 PMCID: PMC8437785 DOI: 10.1016/j.isci.2021.103036] [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: 10/05/2020] [Revised: 06/09/2021] [Accepted: 08/23/2021] [Indexed: 11/24/2022] Open
Abstract
Processive exoribonucleases are executors of RNA decay. In humans, their physical but not functional interactions were thoughtfully investigated. Here we have screened cells deficient in DIS3, XRN2, EXOSC10, DIS3L, and DIS3L2 with a custom siRNA library and determined their genetic interactions (GIs) with diverse pathways of RNA metabolism. We uncovered a complex network of positive interactions that buffer alterations in RNA degradation and reveal reciprocal cooperation with genes involved in transcription, RNA export, and splicing. Further, we evaluated the functional distinctness of nuclear DIS3 and cytoplasmic DIS3L using a library of all known genes associated with RNA metabolism. Our analysis revealed that DIS3 mutation suppresses RNA splicing deficiency, while DIS3L GIs disclose the interplay of cytoplasmic RNA degradation with nuclear RNA processing. Finally, genome-wide DIS3 GI map uncovered relations with genes not directly involved in RNA metabolism, like microtubule organization or regulation of telomerase activity.
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Affiliation(s)
- Anna Hojka-Osinska
- International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Aleksander Chlebowski
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Joanna Grochowska
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Ewelina P. Owczarek
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Kamila Affek
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
| | | | - Roman J. Szczesny
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
| | - Andrzej Dziembowski
- International Institute of Molecular and Cell Biology, 02-109 Warsaw, Poland
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, 02-106 Warsaw, Poland
- Department of Genetics and Biotechnology, Faculty of Biology, University of Warsaw, 02-096 Warsaw, Poland
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26
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Tanu T, Taniue K, Imamura K, Onoguchi-Mizutani R, Han H, Jensen TH, Akimitsu N. hnRNPH1-MTR4 complex-mediated regulation of NEAT1v2 stability is critical for IL8 expression. RNA Biol 2021; 18:537-547. [PMID: 34470577 DOI: 10.1080/15476286.2021.1971439] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Many long noncoding RNAs (lncRNAs) are localized in the nucleus and play important roles in various biological processes, including cell proliferation, differentiation and antiviral response. Yet, it remains unclear how some nuclear lncRNAs are turned over. Here we show that the heterogeneous nuclear ribonucleoprotein H1 (hnRNPH1) controls expression levels of NEAT1v2, a lncRNA involved in the formation of nuclear paraspeckles. hnRNPH1 associates, in an RNA-independent manner, with the RNA helicase MTR4/MTREX, an essential co-factor of the nuclear ribonucleolytic RNA exosome. hnRNPH1 localizes in nuclear speckles and depletion of hnRNPH1 enhances NEAT1v2-mediated expression of the IL8 mRNA, encoding a cytokine involved in the innate immune response. Taken together, our results indicate that the hnRNPH1-MTR4 linkage regulates IL8 expression through the degradation of NEAT1v2 RNA.
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Affiliation(s)
- Tanzina Tanu
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Kenzui Taniue
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Katsutoshi Imamura
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
| | | | - Han Han
- Isotope Science Center, The University of Tokyo, Tokyo, Japan
| | - Torben Heick Jensen
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus C, Denmark
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27
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Machado de Amorim A, Chakrabarti S. Assembly of multicomponent machines in RNA metabolism: A common theme in mRNA decay pathways. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 13:e1684. [PMID: 34351053 DOI: 10.1002/wrna.1684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/07/2021] [Accepted: 07/08/2021] [Indexed: 11/05/2022]
Abstract
Multicomponent protein-RNA complexes comprising a ribonuclease and partner RNA helicase facilitate the turnover of mRNA in all domains of life. While these higher-order complexes provide an effective means of physically and functionally coupling the processes of RNA remodeling and decay, most ribonucleases and RNA helicases do not exhibit sequence specificity in RNA binding. This raises the question as to how these assemblies select substrates for processing and how the activities are orchestrated at the precise moment to ensure efficient decay. The answers to these apparent puzzles lie in the auxiliary components of the assemblies that might relay decay-triggering signals. Given their function within the assemblies, these components may be viewed as "sensors." The functions and mechanisms of action of the sensor components in various degradation complexes in bacteria and eukaryotes are highlighted here to discuss their roles in RNA decay processes. This article is categorized under: RNA Turnover and Surveillance > Regulation of RNA Stability RNA Turnover and Surveillance > Turnover/Surveillance Mechanisms RNA Interactions with Proteins and Other Molecules > Protein-RNA Recognition.
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Affiliation(s)
| | - Sutapa Chakrabarti
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Berlin, Germany
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28
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Blatt P, Wong-Deyrup SW, McCarthy A, Breznak S, Hurton MD, Upadhyay M, Bennink B, Camacho J, Lee MT, Rangan P. RNA degradation is required for the germ-cell to maternal transition in Drosophila. Curr Biol 2021; 31:2984-2994.e7. [PMID: 33989522 PMCID: PMC8319052 DOI: 10.1016/j.cub.2021.04.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 03/26/2021] [Accepted: 04/20/2021] [Indexed: 10/21/2022]
Abstract
In sexually reproducing animals, the oocyte contributes a large supply of RNAs that are essential to launch development upon fertilization. The mechanisms that regulate the composition of the maternal RNA contribution during oogenesis are unclear. Here, we show that a subset of RNAs expressed during the early stages of oogenesis is subjected to regulated degradation during oocyte specification. Failure to remove these RNAs results in oocyte dysfunction and death. We identify the RNA-degrading Super Killer complex and No-Go Decay factor Pelota as key regulators of oogenesis via targeted degradation of specific RNAs expressed in undifferentiated germ cells. These regulators target RNAs enriched for cytidine sequences that are bound by the polypyrimidine tract binding protein Half pint. Thus, RNA degradation helps orchestrate a germ cell-to-maternal transition that gives rise to the maternal contribution to the zygote.
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Affiliation(s)
- Patrick Blatt
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222
| | - Siu Wah Wong-Deyrup
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222
| | - Alicia McCarthy
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222; 10x Genomics, Inc., 6230 Stoneridge Mall Road, Pleasanton, CA, 94588
| | - Shane Breznak
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222
| | - Matthew D Hurton
- University of Pittsburgh, Department of Biological Sciences; 4249 Fifth Avenue, Pittsburgh, PA 15260
| | - Maitreyi Upadhyay
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222; Department of Stem Cell and Regenerative Biology, Sherman Fairchild 100, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138
| | - Benjamin Bennink
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222
| | - Justin Camacho
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222
| | - Miler T Lee
- University of Pittsburgh, Department of Biological Sciences; 4249 Fifth Avenue, Pittsburgh, PA 15260.
| | - Prashanth Rangan
- University at Albany, Department of Biological Sciences, RNA Institute; 1400 Washington Avenue, LSRB 2033D, Albany, NY 12222.
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29
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Translational regulation in pathogenic and beneficial plant-microbe interactions. Biochem J 2021; 478:2775-2788. [PMID: 34297042 DOI: 10.1042/bcj20210066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 07/01/2021] [Accepted: 07/02/2021] [Indexed: 11/17/2022]
Abstract
Plants are surrounded by a vast diversity of microorganisms. Limiting pathogenic microorganisms is crucial for plant survival. On the other hand, the interaction of plants with beneficial microorganisms promotes their growth or allows them to overcome nutrient deficiencies. Balancing the number and nature of these interactions is crucial for plant growth and development, and thus, for crop productivity in agriculture. Plants use sophisticated mechanisms to recognize pathogenic and beneficial microorganisms and genetic programs related to immunity or symbiosis. Although most research has focused on characterizing changes in the transcriptome during plant-microbe interactions, the application of techniques such as Translating Ribosome Affinity Purification (TRAP) and Ribosome profiling allowed examining the dynamic association of RNAs to the translational machinery, highlighting the importance of the translational level of control of gene expression in both pathogenic and beneficial interactions. These studies revealed that the transcriptional and the translational responses are not always correlated, and that translational control operates at cell-specific level. In addition, translational control is governed by cis-elements present in the 5'mRNA leader of regulated mRNAs, e.g. upstream open reading frames (uORFs) and sequence-specific motifs. In this review, we summarize and discuss the recent advances made in the field of translational control during pathogenic and beneficial plant-microbe interactions.
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30
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Li Y, Zhong X, Ye J, Guo H, Long Y. Proteome of Saccharomyces cerevisiae under paraquat stress regulated by therapeutic concentration of copper ions. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 217:112245. [PMID: 33894630 DOI: 10.1016/j.ecoenv.2021.112245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/29/2021] [Accepted: 04/07/2021] [Indexed: 06/12/2023]
Abstract
Paraquat (PQ) is a non-selective herbicide with strong toxicity to humans and mammals. However, the proteome regulation of cells by PQ is still unclear, limiting the development of effective antidotes. Studies have shown that a slight excess of intracellular copper levels could be beneficial to the survival under exposure to PQ. In this study, Saccharomyces cerevisiae was used as a model to explore the regulation effect of copper ions on PQ poisoning by the approach of date independent acquisition proteomics. The results showed that toxic effect of PQ was primarily induced by oxidative damage in the mitochondria and the disorder of gene expression. The addition of Cu2+ involved a series of favorable reactions to cell survival under PQ stress, including activation of the mitogen-activated protein kinase signaling pathway, regulation of processes such as sulfur metabolism, carbon metabolism and gene expression in cells. The generation of glutathione, heme and steroids advantageous to cell growth under stress was also increased. These findings inferred that therapeutic concentration of copper ions could prolong the survival of cells under PQ stress.
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Affiliation(s)
- Yani Li
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Xing Zhong
- Department of Ultrasound, The First Affiliated Hospital of Jinan University, Guangzhou 510630, China
| | - Jinshao Ye
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China.
| | - Huiying Guo
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
| | - Yan Long
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, China
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31
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The zinc-finger protein Red1 orchestrates MTREC submodules and binds the Mtl1 helicase arch domain. Nat Commun 2021; 12:3456. [PMID: 34103492 PMCID: PMC8187409 DOI: 10.1038/s41467-021-23565-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/05/2021] [Indexed: 12/02/2022] Open
Abstract
Cryptic unstable transcripts (CUTs) are rapidly degraded by the nuclear exosome in a process requiring the RNA helicase Mtr4 and specific adaptor complexes for RNA substrate recognition. The PAXT and MTREC complexes have recently been identified as homologous exosome adaptors in human and fission yeast, respectively. The eleven-subunit MTREC comprises the zinc-finger protein Red1 and the Mtr4 homologue Mtl1. Here, we use yeast two-hybrid and pull-down assays to derive a detailed interaction map. We show that Red1 bridges MTREC submodules and serves as the central scaffold. In the crystal structure of a minimal Mtl1/Red1 complex an unstructured region adjacent to the Red1 zinc-finger domain binds to both the Mtl1 KOW domain and stalk helices. This interaction extends the canonical interface seen in Mtr4-adaptor complexes. In vivo mutational analysis shows that this interface is essential for cell survival. Our results add to Mtr4 versatility and provide mechanistic insights into the MTREC complex. The human PAXT complex and the MTREC complex in fission yeast are important exosome cofactors, serving in the degradation of specific noncoding RNAs. Here, the authors combine structural, biochemical and in vivo methods to show how Red1 recruits the Mtl1 helicase by an interface not seen before in helicase-adaptor complexes.
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32
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Patent highlights December 2020-January 2021. Pharm Pat Anal 2021; 10:103-110. [PMID: 34003025 DOI: 10.4155/ppa-2021-0005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.
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33
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D'Orazio KN, Green R. Ribosome states signal RNA quality control. Mol Cell 2021; 81:1372-1383. [PMID: 33713598 PMCID: PMC8041214 DOI: 10.1016/j.molcel.2021.02.022] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 02/04/2021] [Accepted: 02/17/2021] [Indexed: 12/18/2022]
Abstract
Eukaryotic cells integrate multiple quality control (QC) responses during protein synthesis in the cytoplasm. These QC responses are signaled by slow or stalled elongating ribosomes. Depending on the nature of the delay, the signal may lead to translational repression, messenger RNA decay, ribosome rescue, and/or nascent protein degradation. Here, we discuss how the structure and composition of an elongating ribosome in a troubled state determine the downstream quality control pathway(s) that ensue. We highlight the intersecting pathways involved in RNA decay and the crosstalk that occurs between RNA decay and ribosome rescue.
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Affiliation(s)
- Karole N D'Orazio
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Rachel Green
- Department of Molecular Biology and Genetics, Howard Hughes Medical Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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34
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Yadav VK, Claeys Bouuaert C. Mechanism and Control of Meiotic DNA Double-Strand Break Formation in S. cerevisiae. Front Cell Dev Biol 2021; 9:642737. [PMID: 33748134 PMCID: PMC7968521 DOI: 10.3389/fcell.2021.642737] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 02/01/2021] [Indexed: 12/17/2022] Open
Abstract
Developmentally programmed formation of DNA double-strand breaks (DSBs) by Spo11 initiates a recombination mechanism that promotes synapsis and the subsequent segregation of homologous chromosomes during meiosis. Although DSBs are induced to high levels in meiosis, their formation and repair are tightly regulated to minimize potentially dangerous consequences for genomic integrity. In S. cerevisiae, nine proteins participate with Spo11 in DSB formation, but their molecular functions have been challenging to define. Here, we describe our current view of the mechanism of meiotic DSB formation based on recent advances in the characterization of the structure and function of DSB proteins and discuss regulatory pathways in the light of recent models.
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Affiliation(s)
| | - Corentin Claeys Bouuaert
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain, Louvain-La-Neuve, Belgium
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35
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Donsbach P, Klostermeier D. Regulation of RNA helicase activity: principles and examples. Biol Chem 2021; 402:529-559. [PMID: 33583161 DOI: 10.1515/hsz-2020-0362] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/29/2021] [Indexed: 12/16/2022]
Abstract
RNA helicases are a ubiquitous class of enzymes involved in virtually all processes of RNA metabolism, from transcription, mRNA splicing and export, mRNA translation and RNA transport to RNA degradation. Although ATP-dependent unwinding of RNA duplexes is their hallmark reaction, not all helicases catalyze unwinding in vitro, and some in vivo functions do not depend on duplex unwinding. RNA helicases are divided into different families that share a common helicase core with a set of helicase signature motives. The core provides the active site for ATP hydrolysis, a binding site for non-sequence-specific interaction with RNA, and in many cases a basal unwinding activity. Its activity is often regulated by flanking domains, by interaction partners, or by self-association. In this review, we summarize the regulatory mechanisms that modulate the activities of the helicase core. Case studies on selected helicases with functions in translation, splicing, and RNA sensing illustrate the various modes and layers of regulation in time and space that harness the helicase core for a wide spectrum of cellular tasks.
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Affiliation(s)
- Pascal Donsbach
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 30, D-48149Münster, Germany
| | - Dagmar Klostermeier
- Institute for Physical Chemistry, University of Münster, Corrensstrasse 30, D-48149Münster, Germany
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36
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Cabrera-Quio LE, Schleiffer A, Mechtler K, Pauli A. Zebrafish Ski7 tunes RNA levels during the oocyte-to-embryo transition. PLoS Genet 2021; 17:e1009390. [PMID: 33600438 PMCID: PMC7924785 DOI: 10.1371/journal.pgen.1009390] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 03/02/2021] [Accepted: 02/01/2021] [Indexed: 12/13/2022] Open
Abstract
Post-transcriptional regulation of gene expression is crucial during the oocyte-to-embryo transition, a highly dynamic process characterized by the absence of nuclear transcription. Thus, changes to the RNA content are solely dependent on RNA degradation. Although several mechanisms that promote RNA decay during embryogenesis have been identified, it remains unclear which machineries contribute to remodeling the maternal transcriptome. Here, we focused on the degradation factor Ski7 in zebrafish. Homozygous ski7 mutant fish had higher proportions of both poor quality eggs and eggs that were unable to develop beyond the one-cell stage. Consistent with the idea that Ski7 participates in remodeling the maternal RNA content, transcriptome profiling identified hundreds of misregulated mRNAs in the absence of Ski7. Furthermore, upregulated genes were generally lowly expressed in wild type, suggesting that Ski7 maintains low transcript levels for this subset of genes. Finally, GO enrichment and proteomic analyses of misregulated factors implicated Ski7 in the regulation of redox processes. This was confirmed experimentally by an increased resistance of ski7 mutant embryos to reductive stress. Our results provide first insights into the physiological role of vertebrate Ski7 as a post-transcriptional regulator during the oocyte-to-embryo transition.
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Affiliation(s)
| | - Alexander Schleiffer
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
| | - Karl Mechtler
- Institute of Molecular Biotechnology, IMBA, Campus Vienna-Biocenter (VBC), Vienna, Austria
| | - Andrea Pauli
- Research Institute of Molecular Pathology (IMP), Vienna Biocenter (VBC), Vienna, Austria
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37
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Olsen KJ, Johnson SJ. Mtr4 RNA helicase structures and interactions. Biol Chem 2021; 402:605-616. [PMID: 33857361 DOI: 10.1515/hsz-2020-0329] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 12/10/2020] [Indexed: 01/19/2023]
Abstract
Mtr4 is a Ski2-like RNA helicase that plays a central role in RNA surveillance and degradation pathways as an activator of the RNA exosome. Multiple crystallographic and cryo-EM studies over the past 10 years have revealed important insight into the Mtr4 structure and interactions with protein and nucleic acid binding partners. These structures place Mtr4 at the center of a dynamic process that recruits RNA substrates and presents them to the exosome. In this review, we summarize the available Mtr4 structures and highlight gaps in our current understanding.
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Affiliation(s)
- Keith J Olsen
- Department of Chemistry and Biochemistry, Utah State University, Logan, UT84322-0300, USA
| | - Sean J Johnson
- Department of Chemistry and Biochemistry, Utah State University, Logan, UT84322-0300, USA
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38
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Structural and functional characterization of the Spo11 core complex. Nat Struct Mol Biol 2021; 28:92-102. [PMID: 33398171 PMCID: PMC7855791 DOI: 10.1038/s41594-020-00534-w] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 10/08/2020] [Indexed: 12/19/2022]
Abstract
Spo11, which makes DNA double-strand breaks (DSBs) essential for meiotic recombination, has long been recalcitrant to biochemical study. We provide molecular analysis of S. cerevisiae Spo11 purified with partners Rec102, Rec104 and Ski8. Rec102 and Rec104 jointly resemble the B subunit of archaeal Topoisomerase VI, with Rec104 occupying a position similar to the Top6B GHKL-type ATPase domain. Unexpectedly, the Spo11 complex is monomeric (1:1:1:1 stoichiometry), consistent with dimerization controlling DSB formation. Reconstitution of DNA binding reveals topoisomerase-like preferences for duplex-duplex junctions and bent DNA. Spo11 also binds noncovalently but with high affinity to DNA ends mimicking cleavage products, suggesting a mechanism to cap DSB ends. Mutations that reduce DNA binding in vitro attenuate DSB formation, alter DSB processing, and reshape the DSB landscape in vivo. Our data reveal structural and functional similarities between the Spo11 core complex and Topo VI, but also highlight differences reflecting their distinct biological roles.
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39
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Basu S, Mallik S, Hait S, Kundu S. Genome-scale molecular principles of mRNA half-life regulation in yeast. FEBS J 2020; 288:3428-3447. [PMID: 33319437 DOI: 10.1111/febs.15670] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 11/07/2020] [Accepted: 12/11/2020] [Indexed: 12/22/2022]
Abstract
Precise control of protein and messenger RNA (mRNA) degradation is essential for cellular metabolism and homeostasis. Controlled and specific degradation of both molecular species necessitates their engagements with the respective degradation machineries; this engagement involves a disordered/unstructured segment of the substrate traversing the degradation tunnel of the machinery and accessing the catalytic sites. However, while molecular factors influencing protein degradation have been extensively explored on a genome scale, and in multiple organisms, such a comprehensive understanding remains missing for mRNAs. Here, we analyzed multiple genome-scale experimental yeast mRNA half-life data in light of experimentally derived mRNA secondary structures and protein binding data, along with high-resolution X-ray crystallographic structures of the RNase machines. Results unraveled a consistent genome-scale trend that mRNAs comprising longer terminal and/or internal unstructured segments have significantly shorter half-lives; the lengths of the 5'-terminal, 3'-terminal, and internal unstructured segments that affect mRNA half-life are compatible with molecular structures of the 5' exo-, 3' exo-, and endoribonuclease machineries. Sequestration into ribonucleoprotein complexes elongates mRNA half-life, presumably by burying ribonuclease engagement sites under oligomeric interfaces. After gene duplication, differences in terminal unstructured lengths, proportions of internal unstructured segments, and oligomerization modes result in significantly altered half-lives of paralogous mRNAs. Side-by-side comparison of molecular principles underlying controlled protein and mRNA degradation in yeast unravels their remarkable mechanistic similarities and suggests how the intrinsic structural features of the two molecular species, at two different levels of the central dogma, regulate their half-lives on genome scale.
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Affiliation(s)
- Sudipto Basu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India.,Center of Excellence in Systems Biology and Biomedical Engineering (TEQIP Phase-III), University of Calcutta, Kolkata, India
| | - Saurav Mallik
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Suman Hait
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India
| | - Sudip Kundu
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, Kolkata, India.,Center of Excellence in Systems Biology and Biomedical Engineering (TEQIP Phase-III), University of Calcutta, Kolkata, India
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40
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Weston S, Baracco L, Keller C, Matthews K, McGrath ME, Logue J, Liang J, Dyall J, Holbrook MR, Hensley LE, Jahrling PB, Yu W, MacKerell AD, Frieman MB. The SKI complex is a broad-spectrum, host-directed antiviral drug target for coronaviruses, influenza, and filoviruses. Proc Natl Acad Sci U S A 2020; 117:30687-30698. [PMID: 33184176 PMCID: PMC7720140 DOI: 10.1073/pnas.2012939117] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The SARS-CoV-2 pandemic has made it clear that we have a desperate need for antivirals. We present work that the mammalian SKI complex is a broad-spectrum, host-directed, antiviral drug target. Yeast suppressor screening was utilized to find a functional genetic interaction between proteins from influenza A virus (IAV) and Middle East respiratory syndrome coronavirus (MERS-CoV) with eukaryotic proteins that may be potential host factors involved in replication. This screening identified the SKI complex as a potential host factor for both viruses. In mammalian systems siRNA-mediated knockdown of SKI genes inhibited replication of IAV and MERS-CoV. In silico modeling and database screening identified a binding pocket on the SKI complex and compounds predicted to bind. Experimental assays of those compounds identified three chemical structures that were antiviral against IAV and MERS-CoV along with the filoviruses Ebola and Marburg and two further coronaviruses, SARS-CoV and SARS-CoV-2. The mechanism of antiviral activity is through inhibition of viral RNA production. This work defines the mammalian SKI complex as a broad-spectrum antiviral drug target and identifies lead compounds for further development.
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Affiliation(s)
- Stuart Weston
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Lauren Baracco
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Chloe Keller
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Krystal Matthews
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Marisa E McGrath
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - James Logue
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Janie Liang
- Integrated Research Facility, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702
| | - Julie Dyall
- Integrated Research Facility, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702
| | - Michael R Holbrook
- Integrated Research Facility, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702
| | - Lisa E Hensley
- Integrated Research Facility, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702
| | - Peter B Jahrling
- Integrated Research Facility, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702
- Emerging Viral Pathogens Section, National Institute of Allergy and Infectious Diseases, NIH, Frederick, MD 21702
| | - Wenbo Yu
- Center for Biomolecular Therapeutics, University of Maryland School of Medicine, Baltimore, MD 21201
- University of Maryland Computer-Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201
| | - Alexander D MacKerell
- Center for Biomolecular Therapeutics, University of Maryland School of Medicine, Baltimore, MD 21201
- University of Maryland Computer-Aided Drug Design Center, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, MD 21201
| | - Matthew B Frieman
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD 21201;
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41
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Weick EM, Lima CD. RNA helicases are hubs that orchestrate exosome-dependent 3'-5' decay. Curr Opin Struct Biol 2020; 67:86-94. [PMID: 33147539 DOI: 10.1016/j.sbi.2020.09.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/14/2020] [Accepted: 09/20/2020] [Indexed: 01/10/2023]
Abstract
The RNA exosome is a conserved complex of proteins that mediates 3'-5' RNA processing and decay. Its functions range from processing of non-coding RNAs such as ribosomal RNAs and decay of aberrant transcripts in the nucleus to cytoplasmic mRNA turnover and quality control. Ski2-like RNA helicases translocate substrates to exosome-associated ribonucleases and interact with the RNA exosome either directly or as part of multi-subunit helicase-containing complexes that identify and target RNA substrates for decay. Recent structures of these helicases with their RNA-binding partners or the RNA exosome have advanced our understanding of a system of modular and mutually exclusive contacts between the exosome and exosome-associated helicase complexes that shape the transcriptome by orchestrating exosome-dependent 3'-5' decay.
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Affiliation(s)
- Eva-Maria Weick
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | - Christopher D Lima
- Structural Biology Program, Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA; Howard Hughes Medical Institute, 1275 York Avenue, New York, NY 10065, USA.
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42
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43
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Abstract
In this issue of Structure, Absmeier et al. (2020) describe the molecular mechanisms employed by an RNA helicase to prevent premature ATP hydrolysis upon nucleotide binding.
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44
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Quantitative Proteomics of the Cancer Cell Line Encyclopedia. Cell 2020; 180:387-402.e16. [PMID: 31978347 DOI: 10.1016/j.cell.2019.12.023] [Citation(s) in RCA: 480] [Impact Index Per Article: 120.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Revised: 10/14/2019] [Accepted: 12/13/2019] [Indexed: 01/22/2023]
Abstract
Proteins are essential agents of biological processes. To date, large-scale profiling of cell line collections including the Cancer Cell Line Encyclopedia (CCLE) has focused primarily on genetic information whereas deep interrogation of the proteome has remained out of reach. Here, we expand the CCLE through quantitative profiling of thousands of proteins by mass spectrometry across 375 cell lines from diverse lineages to reveal information undiscovered by DNA and RNA methods. We observe unexpected correlations within and between pathways that are largely absent from RNA. An analysis of microsatellite instable (MSI) cell lines reveals the dysregulation of specific protein complexes associated with surveillance of mutation and translation. These and other protein complexes were associated with sensitivity to knockdown of several different genes. These data in conjunction with the wider CCLE are a broad resource to explore cellular behavior and facilitate cancer research.
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45
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Ohnuma K, Kishita Y, Nyuzuki H, Kohda M, Ohtsu Y, Takeo S, Asano T, Sato-Miyata Y, Ohtake A, Murayama K, Okazaki Y, Aigaki T. Ski3/TTC37 deficiency associated with trichohepatoenteric syndrome causes mitochondrial dysfunction in Drosophila. FEBS Lett 2020; 594:2168-2181. [PMID: 32294252 DOI: 10.1002/1873-3468.13792] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Accepted: 03/30/2020] [Indexed: 11/08/2022]
Abstract
Tetratricopeptide repeat protein 37 (TTC37) is a causative gene of trichohepatoenteric syndrome (THES). However, little is known about the pathogenesis of this disease. Here, we characterize the phenotype of a Drosophila model in which ski3, a homolog of TTC37, is disrupted. The mutant flies are pupal lethal, and the pupal lethality is partially rescued by transgenic expression of wild-type ski3 or human TTC37. The mutant larvae show growth retardation, heart arrhythmia, triacylglycerol accumulation, and aberrant metabolism of glycolysis and the TCA cycle. Moreover, mitochondrial membrane potential and respiratory chain complex activities are significantly reduced in the mutants. Our results demonstrate that ski3 deficiency causes mitochondrial dysfunction, which may underlie the pathogenesis of THES.
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Affiliation(s)
- Kohei Ohnuma
- Department of Biological Sciences, Graduate School of Science and Engineering, Tokyo Metropolitan University, Hachioji-shi, Japan
| | - Yoshihito Kishita
- Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Japan
| | - Hiromi Nyuzuki
- Department of Pediatrics, School of Medicine, Niigata University, Asahimachi, Japan
| | - Masakazu Kohda
- Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Japan
| | - Yuta Ohtsu
- Division of Medical Nutrition, Faculty of Healthcare, Tokyo Healthcare University, Setagaya-ku, Japan
| | - Satomi Takeo
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Hachioji-shi, Japan
| | - Tsunaki Asano
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Hachioji-shi, Japan
| | - Yukiko Sato-Miyata
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Hachioji-shi, Japan
- Research and Education Centre for Natural Sciences, Keio University, Yokohama, Japan
| | - Akira Ohtake
- Department of Pediatrics & Clinical Genomics, Saitama Medical University, Iruma-gun, Japan
| | - Kei Murayama
- Department of Metabolism, Center for Medical Genetics, Chiba Children's Hospital, Midori-ku, Japan
| | - Yasushi Okazaki
- Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Bunkyo-ku, Japan
| | - Toshiro Aigaki
- Department of Biological Sciences, Graduate School of Science, Tokyo Metropolitan University, Hachioji-shi, Japan
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46
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Tuck AC, Rankova A, Arpat AB, Liechti LA, Hess D, Iesmantavicius V, Castelo-Szekely V, Gatfield D, Bühler M. Mammalian RNA Decay Pathways Are Highly Specialized and Widely Linked to Translation. Mol Cell 2020; 77:1222-1236.e13. [PMID: 32048998 PMCID: PMC7083229 DOI: 10.1016/j.molcel.2020.01.007] [Citation(s) in RCA: 55] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 11/11/2019] [Accepted: 01/07/2020] [Indexed: 12/24/2022]
Abstract
RNA decay is crucial for mRNA turnover and surveillance and misregulated in many diseases. This complex system is challenging to study, particularly in mammals, where it remains unclear whether decay pathways perform specialized versus redundant roles. Cytoplasmic pathways and links to translation are particularly enigmatic. By directly profiling decay factor targets and normal versus aberrant translation in mouse embryonic stem cells (mESCs), we uncovered extensive decay pathway specialization and crosstalk with translation. XRN1 (5'-3') mediates cytoplasmic bulk mRNA turnover whereas SKIV2L (3'-5') is universally recruited by ribosomes, tackling aberrant translation and sometimes modulating mRNA abundance. Further exploring translation surveillance revealed AVEN and FOCAD as SKIV2L interactors. AVEN prevents ribosome stalls at structured regions, which otherwise require SKIV2L for clearance. This pathway is crucial for histone translation, upstream open reading frame (uORF) regulation, and counteracting ribosome arrest on small ORFs. In summary, we uncovered key targets, components, and functions of mammalian RNA decay pathways and extensive coupling to translation.
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Affiliation(s)
- Alex Charles Tuck
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Aneliya Rankova
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Alaaddin Bulak Arpat
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Luz Angelica Liechti
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Daniel Hess
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | - Vytautas Iesmantavicius
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland
| | | | - David Gatfield
- Center for Integrative Genomics, University of Lausanne, 1015 Lausanne, Switzerland
| | - Marc Bühler
- Friedrich Miescher Institute for Biomedical Research, Maulbeerstrasse 66, 4058 Basel, Switzerland; University of Basel, Petersplatz 10, 4003 Basel, Switzerland.
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47
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Zinoviev A, Ayupov RK, Abaeva IS, Hellen CUT, Pestova TV. Extraction of mRNA from Stalled Ribosomes by the Ski Complex. Mol Cell 2020; 77:1340-1349.e6. [PMID: 32006463 DOI: 10.1016/j.molcel.2020.01.011] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 11/13/2019] [Accepted: 01/07/2020] [Indexed: 11/26/2022]
Abstract
The evolutionarily conserved Ski2-Ski3-Ski8 (Ski) complex containing the 3'→5' RNA helicase Ski2 binds to 80S ribosomes near the mRNA entrance and facilitates 3'→5' exosomal degradation of mRNA during ribosome-associated mRNA surveillance pathways. Here, we assayed Ski's activity using an in vitro reconstituted translation system and report that this complex efficiently extracts mRNA from 80S ribosomes in the 3'→5' direction in a nucleotide-by-nucleotide manner. The process is ATP dependent and can occur on pre- and post-translocation ribosomal complexes. The Ski complex can engage productively with mRNA and extract it from 80S complexes containing as few as 19 (but not 13) 3'-terminal mRNA nucleotides starting from the P site. The mRNA-extracting activity of the Ski complex suggests that its role in mRNA quality control pathways is not limited to acceleration of exosomal degradation and could include clearance of stalled ribosomes from mRNA, poising mRNA for degradation and rendering stalled ribosomes recyclable by Pelota/Hbs1/ABCE1.
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Affiliation(s)
- Alexandra Zinoviev
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Rustam K Ayupov
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Irina S Abaeva
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Christopher U T Hellen
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Tatyana V Pestova
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA.
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48
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Keidel A, Conti E, Falk S. Purification and Reconstitution of the S. cerevisiae TRAMP and Ski Complexes for Biochemical and Structural Studies. Methods Mol Biol 2020; 2062:491-513. [PMID: 31768992 DOI: 10.1007/978-1-4939-9822-7_24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The RNA exosome is a macromolecular machine that degrades a large variety of RNAs from their 3'-end. It comprises the major 3'-to-5' exonuclease in the cell, completely degrades erroneous and overly abundant RNAs, and is also involved in the precise processing of RNAs. To degrade transcripts both specifically and efficiently the exosome functions together with compartment-specific cofactors. In the yeast S. cerevisiae, the exosome associates with the Ski complex in the cytoplasm and with Mtr4 alone or with Mtr4 as part of the TRAMP complex in the nucleus. Here we describe how to produce, purify, and assemble the Ski and TRAMP complexes from S. cerevisiae.
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Affiliation(s)
- Achim Keidel
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Martinsried, Germany
| | - Elena Conti
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Martinsried, Germany.
| | - Sebastian Falk
- Department of Structural Cell Biology, Max-Planck-Institute of Biochemistry, Martinsried, Germany.
- Max Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, Vienna, Austria.
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49
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Abstract
The RNA exosome is a ribonucleolytic multiprotein complex that is conserved and essential in all eukaryotes. Although we tend to speak of "the" exosome complex, it should be more correctly viewed as several different subtypes that share a common core. Subtypes of the exosome complex are present in the cytoplasm, the nucleus and the nucleolus of all eukaryotic cells, and carry out the 3'-5' processing and/or degradation of a wide range of RNA substrates.Because the substrate specificity of the exosome complex is determined by cofactors, the system is highly adaptable, and different organisms have adjusted the machinery to their specific needs. Here, we present an overview of exosome complexes and their cofactors that have been described in different eukaryotes.
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Affiliation(s)
- Cornelia Kilchert
- Institut für Biochemie, Justus-Liebig-Universität Gießen, Gießen, Germany.
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50
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Zinoviev A, Hellen CUT, Pestova TV. In Vitro Characterization of the Activity of the Mammalian RNA Exosome on mRNAs in Ribosomal Translation Complexes. Methods Mol Biol 2020; 2062:327-354. [PMID: 31768984 DOI: 10.1007/978-1-4939-9822-7_16] [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] [Indexed: 10/18/2023]
Abstract
The RNA exosome is a multisubunit protein complex that exhibits a 3' to 5' exoribonuclease activity, endoribonuclease activity, and participates in a variety of RNA processing and degradation pathways in both the nucleus and the cytoplasm. Exosomes interact with various cofactors which target them to specific RNA substrates and processes. Investigation of the mechanisms by which mammalian RNA exosomes are targeted to specific RNA substrates requires the development of in vitro approaches for purification of exosomes and their co-factors, assembly of substrates and monitoring of the exosomal activity. Here, we describe protocols for in vitro reconstitution of ribosomal 80S elongation complexes on cap-labeled mRNAs and for assaying exosomal degradation of mRNAs in such complexes depending on the presence of GTPBP1, which has previously been implicated in directing the exosome to mRNA targets.
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Affiliation(s)
- Alexandra Zinoviev
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Christopher U T Hellen
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA
| | - Tatyana V Pestova
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, NY, USA.
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