1
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Qin B, Peng Q, Dong H, Lei L, Wu S. Non-coding RNAs in diabetic foot ulcer- a focus on infected wounds. Diabetes Metab Res Rev 2024; 40:e3740. [PMID: 37839046 DOI: 10.1002/dmrr.3740] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Revised: 07/19/2023] [Accepted: 09/25/2023] [Indexed: 10/17/2023]
Abstract
Diabetes mellitus is associated with a wide range of neuropathies, vasculopathies, and immunopathies, resulting in many complications. More than 30% of diabetic patients risk developing diabetic foot ulcers (DFUs). Non-coding RNAs (ncRNAs), including microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs), play essential roles in various biological functions in the hyperglycaemic environment that determines the development of DFU. Ulceration results in tissue breakdown and skin barrier scavenging, thereby facilitating bacterial infection and biofilm formation. Many bacteria contribute to diabetic foot infection (DFI), including Staphylococcus aureus (S. aureus) et al. A heterogeneous group of "ncRNAs," termed small RNAs (sRNAs), powerfully regulates biofilm formation and DFI healing. Multidisciplinary foot care interventions have been identified for nonhealing ulcers. With an appreciation of the link between disease processes and ncRNAs, a novel therapeutic model of bioactive materials loaded with ncRNAs has been developed to prevent and manage diabetic foot complications.
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Affiliation(s)
- Boquan Qin
- Department of Orthopedic Surgery and Orthopedic Research Institute, Laboratory of Stem Cell and Tissue Engineering, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Qi Peng
- Department of Orthopedic Surgery and Orthopedic Research Institute, Laboratory of Stem Cell and Tissue Engineering, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Hongxian Dong
- Department of Orthopedic Surgery and Orthopedic Research Institute, Laboratory of Stem Cell and Tissue Engineering, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Lei Lei
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Shizhou Wu
- Department of Orthopedic Surgery and Orthopedic Research Institute, Laboratory of Stem Cell and Tissue Engineering, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
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2
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Nakanishi K. When Argonaute takes out the ribonuclease sword. J Biol Chem 2024; 300:105499. [PMID: 38029964 PMCID: PMC10772731 DOI: 10.1016/j.jbc.2023.105499] [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: 07/10/2023] [Revised: 11/11/2023] [Accepted: 11/15/2023] [Indexed: 12/01/2023] Open
Abstract
Argonaute (AGO) proteins in all three domains of life form ribonucleoprotein or deoxyribonucleoprotein complexes by loading a guide RNA or DNA, respectively. Since all AGOs retain a PIWI domain that takes an RNase H fold, the ancestor was likely an endoribonuclease (i.e., a slicer). In animals, most miRNA-mediated gene silencing occurs slicer independently. However, the slicer activity of AGO is indispensable in specific events, such as development and differentiation, which are critical for vertebrates and thus cannot be replaced by the slicer-independent regulation. This review highlights the distinctions in catalytic activation mechanisms among slicing-competent AGOs, shedding light on the roles of two metal ions in target recognition and cleavage. The precision of the target specificity by the RNA-induced silencing complexes is reevaluated and redefined. The possible coevolutionary relationship between slicer-independent gene regulation and AGO-binding protein, GW182, is also explored. These discussions reveal that numerous captivating questions remain unanswered regarding the timing and manner in which AGOs employ their slicing activity.
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Affiliation(s)
- Kotaro Nakanishi
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, Ohio, USA; Center for RNA Biology, The Ohio State University, Columbus, Ohio, USA.
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3
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Sala L, Kumar M, Prajapat M, Chandrasekhar S, Cosby RL, La Rocca G, Macfarlan TS, Awasthi P, Chari R, Kruhlak M, Vidigal JA. AGO2 silences mobile transposons in the nucleus of quiescent cells. Nat Struct Mol Biol 2023; 30:1985-1995. [PMID: 37985687 DOI: 10.1038/s41594-023-01151-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 09/27/2023] [Indexed: 11/22/2023]
Abstract
Argonaute 2 (AGO2) is a cytoplasmic component of the miRNA pathway, with essential roles in development and disease. Yet little is known about its regulation in vivo. Here we show that in quiescent mouse splenocytes, AGO2 localizes almost exclusively to the nucleus. AGO2 subcellular localization is modulated by the Pi3K-AKT-mTOR pathway, a well-established regulator of quiescence. Signaling through this pathway in proliferating cells promotes AGO2 cytoplasmic accumulation, at least in part by stimulating the expression of TNRC6, an essential AGO2 binding partner in the miRNA pathway. In quiescent cells in which mTOR signaling is low, AGO2 accumulates in the nucleus, where it binds to young mobile transposons co-transcriptionally to repress their expression via its catalytic domain. Our data point to an essential but previously unrecognized nuclear role for AGO2 during quiescence as part of a genome-defense system against young mobile elements and provide evidence of RNA interference in the soma of mammals.
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Affiliation(s)
- Laura Sala
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, The National Institutes of Health, Bethesda, MD, USA
| | - Manish Kumar
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, The National Institutes of Health, Bethesda, MD, USA
| | - Mahendra Prajapat
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, The National Institutes of Health, Bethesda, MD, USA
| | - Srividya Chandrasekhar
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, The National Institutes of Health, Bethesda, MD, USA
| | - Rachel L Cosby
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, The National Institutes of Health, Bethesda, MD, USA
- The National Institute for General Medical Sciences, The National Institutes of Health, Bethesda, MD, USA
| | - Gaspare La Rocca
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Todd S Macfarlan
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development, The National Institutes of Health, Bethesda, MD, USA
| | - Parirokh Awasthi
- Laboratory Animal Sciences Program, Frederick National Lab for Cancer Research, The National Institutes of Health, Frederick, MD, USA
| | - Raj Chari
- Laboratory Animal Sciences Program, Frederick National Lab for Cancer Research, The National Institutes of Health, Frederick, MD, USA
| | - Michael Kruhlak
- CCR Confocal Microscopy Core Facility, National Cancer Institute, The National Institutes of Health, Bethesda, MD, USA
| | - Joana A Vidigal
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, The National Institutes of Health, Bethesda, MD, USA.
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4
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Petri BJ, Piell KM, Wahlang B, Head KZ, Rouchka EC, Park JW, Hwang JY, Banerjee M, Cave MC, Klinge CM. Altered splicing factor and alternative splicing events in a mouse model of diet- and polychlorinated biphenyl-induced liver disease. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2023; 103:104260. [PMID: 37683712 PMCID: PMC10591945 DOI: 10.1016/j.etap.2023.104260] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 08/30/2023] [Accepted: 09/04/2023] [Indexed: 09/10/2023]
Abstract
Non-alcoholic fatty liver disease (NAFLD) is associated with human environmental exposure to polychlorinated biphenyls (PCBs). Alternative splicing (AS) is dysregulated in steatotic liver disease and is regulated by splicing factors (SFs) and N-6 methyladenosine (m6A) modification. Here integrated analysis of hepatic mRNA-sequencing data was used to identify differentially expressed SFs and differential AS events (ASEs) in the livers of high fat diet-fed C57BL/6 J male mice exposed to Aroclor1260, PCB126, Aroclor1260 + PCB126, or vehicle control. Aroclor1260 + PCB126 co-exposure altered 100 SFs and replicate multivariate analysis of transcript splicing (rMATS) identified 449 ASEs in 366 genes associated with NAFLD pathways. These ASEs were similar to those resulting from experimental perturbations in m6A writers, readers, and erasers. These results demonstrate specific hepatic SF and AS regulatory mechanisms are disrupted by HFD and PCB exposures, contributing to the expression of altered isoforms that may play a role in NAFLD progression to NASH.
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Affiliation(s)
- Belinda J Petri
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40292, USA
| | - Kellianne M Piell
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40292, USA
| | - Banrida Wahlang
- University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; University of Louisville Hepatobiology and Toxicology Center, USA; The University of Louisville Superfund Research Center, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Kimberly Z Head
- University of Louisville Hepatobiology and Toxicology Center, USA; The University of Louisville Superfund Research Center, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Eric C Rouchka
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40292, USA; KY INBRE Bioinformatics Core, University of Louisville, USA
| | - Juw Won Park
- University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; KY INBRE Bioinformatics Core, University of Louisville, USA; Department of Computer Science and Engineering, University of Louisville, Louisville, KY 40292, USA; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40292 USA
| | - Jae Yeon Hwang
- Department of Computer Science and Engineering, University of Louisville, Louisville, KY 40292, USA
| | - Mayukh Banerjee
- University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40292 USA
| | - Matthew C Cave
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40292, USA; University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA; University of Louisville Hepatobiology and Toxicology Center, USA; The University of Louisville Superfund Research Center, USA; Division of Gastroenterology, Hepatology & Nutrition, Department of Medicine, University of Louisville School of Medicine, USA
| | - Carolyn M Klinge
- Department of Biochemistry & Molecular Genetics, University of Louisville School of Medicine, Louisville, KY 40292, USA; University of Louisville Center for Integrative Environmental Health Sciences (CIEHS), USA.
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5
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Mauro M, Berretta M, Palermo G, Cavalieri V, La Rocca G. The Multiplicity of Argonaute Complexes in Mammalian Cells. J Pharmacol Exp Ther 2023; 384:1-9. [PMID: 35667689 PMCID: PMC9827513 DOI: 10.1124/jpet.122.001158] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2022] [Revised: 05/12/2022] [Accepted: 05/13/2022] [Indexed: 01/12/2023] Open
Abstract
Argonautes (AGOs) are a highly conserved family of proteins found in most eukaryotes and involved in mechanisms of gene regulation, both at the transcriptional and post-transcriptional level. Among other functions, AGO proteins associate with microRNAs (miRNAs) to mediate the post-transcriptional repression of protein-coding genes. In this process, AGOs associate with members of the trinucleotide repeat containing 6 protein (TNRC6) family to form the core of the RNA-induced silencing complex (RISC), the effector machinery that mediates miRNA function. However, the description of the exact composition of the RISC has been a challenging task due to the fact the AGO's interactome is dynamically regulated in a cell type- and condition-specific manner. Here, we summarize some of the most significant studies that have identified AGO complexes in mammalian cells, as well as the approaches used to characterize them. Finally, we discuss possible opportunities to exploit what we have learned on the properties of the RISC to develop novel anti-cancer therapies. SIGNIFICANCE STATEMENT: The RNA-induced silencing complex (RISC) is the molecular machinery that mediates miRNA function in mammals. Studies over the past two decades have shed light on important biochemical and functional properties of this complex. However, many aspects of this complex await further elucidation, mostly due to technical limitations that have hindered full characterization. Here, we summarize some of the most significant studies on the mammalian RISC and discuss possible sources of biases in the approaches used to characterize it.
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Affiliation(s)
- Maurizio Mauro
- Department of Medicine, Albert Einstein College of Medicine, New York, New York (M.M.); Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy (M.B.); Gruppo Oncologico Ricercatori Italiani, GORI ONLUS, Pordenone, Italy (M.B.); Department of Biomedical and Biotechnological Sciences, University of Catania, Catania Italy (G.P.); Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy (V.C.); and Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York (G.L.R.)
| | - Massimiliano Berretta
- Department of Medicine, Albert Einstein College of Medicine, New York, New York (M.M.); Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy (M.B.); Gruppo Oncologico Ricercatori Italiani, GORI ONLUS, Pordenone, Italy (M.B.); Department of Biomedical and Biotechnological Sciences, University of Catania, Catania Italy (G.P.); Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy (V.C.); and Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York (G.L.R.)
| | - Giuseppe Palermo
- Department of Medicine, Albert Einstein College of Medicine, New York, New York (M.M.); Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy (M.B.); Gruppo Oncologico Ricercatori Italiani, GORI ONLUS, Pordenone, Italy (M.B.); Department of Biomedical and Biotechnological Sciences, University of Catania, Catania Italy (G.P.); Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy (V.C.); and Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York (G.L.R.)
| | - Vincenzo Cavalieri
- Department of Medicine, Albert Einstein College of Medicine, New York, New York (M.M.); Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy (M.B.); Gruppo Oncologico Ricercatori Italiani, GORI ONLUS, Pordenone, Italy (M.B.); Department of Biomedical and Biotechnological Sciences, University of Catania, Catania Italy (G.P.); Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy (V.C.); and Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York (G.L.R.)
| | - Gaspare La Rocca
- Department of Medicine, Albert Einstein College of Medicine, New York, New York (M.M.); Department of Clinical and Experimental Medicine, University of Messina, Messina, Italy (M.B.); Gruppo Oncologico Ricercatori Italiani, GORI ONLUS, Pordenone, Italy (M.B.); Department of Biomedical and Biotechnological Sciences, University of Catania, Catania Italy (G.P.); Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy (V.C.); and Cancer Biology and Genetics Program, Memorial Sloan-Kettering Cancer Center, New York, New York (G.L.R.)
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6
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La Rocca G, Cavalieri V. Roles of the Core Components of the Mammalian miRISC in Chromatin Biology. Genes (Basel) 2022; 13:genes13030414. [PMID: 35327968 PMCID: PMC8954937 DOI: 10.3390/genes13030414] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 02/20/2022] [Accepted: 02/23/2022] [Indexed: 12/16/2022] Open
Abstract
The Argonaute (AGO) and the Trinucleotide Repeat Containing 6 (TNRC6) family proteins are the core components of the mammalian microRNA-induced silencing complex (miRISC), the machinery that mediates microRNA function in the cytoplasm. The cytoplasmic miRISC-mediated post-transcriptional gene repression has been established as the canonical mechanism through which AGO and TNRC6 proteins operate. However, growing evidence points towards an additional mechanism through which AGO and TNRC6 regulate gene expression in the nucleus. While several mechanisms through which miRISC components function in the nucleus have been described, in this review we aim to summarize the major findings that have shed light on the role of AGO and TNRC6 in mammalian chromatin biology and on the implications these novel mechanisms may have in our understanding of regulating gene expression.
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Affiliation(s)
- Gaspare La Rocca
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
- Correspondence: (G.L.R.); (V.C.)
| | - Vincenzo Cavalieri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, 90128 Palermo, Italy
- Correspondence: (G.L.R.); (V.C.)
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7
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La Rocca G, King B, Shui B, Li X, Zhang M, Akat KM, Ogrodowski P, Mastroleo C, Chen K, Cavalieri V, Ma Y, Anelli V, Betel D, Vidigal J, Tuschl T, Meister G, Thompson CB, Lindsten T, Haigis K, Ventura A. Inducible and reversible inhibition of miRNA-mediated gene repression in vivo. eLife 2021; 10:70948. [PMID: 34463618 PMCID: PMC8476124 DOI: 10.7554/elife.70948] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 08/24/2021] [Indexed: 12/23/2022] Open
Abstract
Although virtually all gene networks are predicted to be controlled by miRNAs, the contribution of this important layer of gene regulation to tissue homeostasis in adult animals remains unclear. Gain and loss-of-function experiments have provided key insights into the specific function of individual miRNAs, but effective genetic tools to study the functional consequences of global inhibition of miRNA activity in vivo are lacking. Here we report the generation and characterization of a genetically engineered mouse strain in which miRNA-mediated gene repression can be reversibly inhibited without affecting miRNA biogenesis or abundance. We demonstrate the usefulness of this strategy by investigating the consequences of acute inhibition of miRNA function in adult animals. We find that different tissues and organs respond differently to global loss of miRNA function. While miRNA-mediated gene repression is essential for the homeostasis of the heart and the skeletal muscle, it is largely dispensable in the majority of other organs. Even in tissues where it is not required for homeostasis, such as the intestine and hematopoietic system, miRNA activity can become essential during regeneration following acute injury. These data support a model where many metazoan tissues primarily rely on miRNA function to respond to potentially pathogenic events.
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Affiliation(s)
- Gaspare La Rocca
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Bryan King
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Bing Shui
- Department of Cancer Biology, Dana Farber Cancer Institute, Boston, United States
| | - Xiaoyi Li
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States.,Louis V. Gerstner Jr. Graduate School of Biomedical Sciences, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Minsi Zhang
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Kemal M Akat
- Laboratory of RNA Molecular Biology, The Rockefeller University, New York, United States
| | - Paul Ogrodowski
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Chiara Mastroleo
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Kevin Chen
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Vincenzo Cavalieri
- Department of Biological, Chemical and Pharmaceutical Sciences and Technologies, University of Palermo, Palermo, Italy
| | - Yilun Ma
- Weill Cornell/Rockefeller/Sloan-Kettering Tri-Institutional MD-PhD Program, New York, United States
| | - Viviana Anelli
- Center of Integrative Biology, University of Trento, Trento, Italy
| | - Doron Betel
- Hem/Oncology, Medicine and Institution for Computational Biomedicine, Weill Cornell Medical College, New York, United States
| | - Joana Vidigal
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, Bethesda, United States
| | - Thomas Tuschl
- Laboratory of RNA Molecular Biology, The Rockefeller University, New York, United States
| | - Gunter Meister
- Regensburg Center for Biochemistry, University of Regensburg, Regensburg, Germany
| | - Craig B Thompson
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Tullia Lindsten
- Immunology Program, Memorial Sloan Kettering Cancer Center, New York, United States
| | - Kevin Haigis
- Department of Cancer Biology, Dana Farber Cancer Institute, Boston, United States
| | - Andrea Ventura
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, United States
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8
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Nawalpuri B, Sharma A, Chattarji S, Muddashetty RS. Distinct temporal expression of the GW182 paralog TNRC6A in neurons regulates dendritic arborization. J Cell Sci 2021; 134:271120. [PMID: 34328181 DOI: 10.1242/jcs.258465] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 07/19/2021] [Indexed: 01/11/2023] Open
Abstract
Precise development of the dendritic architecture is a critical determinant of mature neuronal circuitry. MicroRNA (miRNA)-mediated regulation of protein synthesis plays a crucial role in dendritic morphogenesis, but the role of miRNA-induced silencing complex (miRISC) protein components in this process is less studied. Here, we show an important role of a key miRISC protein, the GW182 paralog TNRC6A, in the regulation of dendritic growth. We identified a distinct brain region-specific spatiotemporal expression pattern of GW182 during rat postnatal development. We found that the window of peak GW182 expression coincides with the period of extensive dendritic growth, both in the hippocampus and cerebellum. Perturbation of GW182 function during a specific temporal window resulted in reduced dendritic growth of cultured hippocampal neurons. Mechanistically, we show that GW182 modulates dendritic growth by regulating global somatodendritic translation and actin cytoskeletal dynamics of developing neurons. Furthermore, we found that GW182 affects dendritic architecture by regulating the expression of actin modulator LIMK1. Taken together, our data reveal a previously undescribed neurodevelopmental expression pattern of GW182 and its role in dendritic morphogenesis, which involves both translational control and actin cytoskeletal rearrangement. This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Bharti Nawalpuri
- Centre for Brain Development and Repair, Institute for Stem Cell Science and Regenerative Medicine (InStem), Bangalore 560065, India.,School of Chemical and Biotechnology, Shanmugha Arts, Science, and Technology and Research Academy (SASTRA) University, Thanjavur 613401, India.,Centre for Brain Research, Indian Institute of Science, Bangalore 560012, India
| | - Arpita Sharma
- Centre for Brain Development and Repair, Institute for Stem Cell Science and Regenerative Medicine (InStem), Bangalore 560065, India
| | - Sumantra Chattarji
- National Centre for Biological Sciences, Bangalore 560065, India.,Simons Initiative for the Developing Brain and Centre for Discovery Brain Sciences, University of Edinburgh EH8 9XD, Edinburgh, UK
| | - Ravi S Muddashetty
- Centre for Brain Development and Repair, Institute for Stem Cell Science and Regenerative Medicine (InStem), Bangalore 560065, India.,Centre for Brain Research, Indian Institute of Science, Bangalore 560012, India
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9
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Pollari M, De S, Wang A, Mäkinen K. The potyviral silencing suppressor HCPro recruits and employs host ARGONAUTE1 in pro-viral functions. PLoS Pathog 2020; 16:e1008965. [PMID: 33031436 PMCID: PMC7575100 DOI: 10.1371/journal.ppat.1008965] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 10/20/2020] [Accepted: 09/04/2020] [Indexed: 11/19/2022] Open
Abstract
In this study, we demonstrate a novel pro-viral role for the Nicotiana benthamiana ARGONAUTE 1 (AGO1) in potyvirus infection. AGO1 strongly enhanced potato virus A (PVA) particle production and benefited the infection when supplied in excess. We subsequently identified the potyviral silencing suppressor, helper-component protease (HCPro), as the recruiter of host AGO1. After the identification of a conserved AGO1-binding GW/WG motif in potyviral HCPros, we used site-directed mutagenesis to introduce a tryptophan-to-alanine change into the HCPro (HCProAG) of PVA (PVAAG) and turnip mosaic virus (TuMVAG). AGO1 co-localization and co-immunoprecipitation with PVA HCPro was significantly reduced by the mutation suggesting the interaction was compromised. Although the mutation did not interfere with HCPro's complementation or silencing suppression capacity, it nevertheless impaired virus particle accumulation and the systemic spread of both PVA and TuMV. Furthermore, we found that the HCPro-AGO1 interaction was important for AGO1's association with the PVA coat protein. The coat protein was also more stable in wild type PVA infection than in PVAAG infection. Based on these findings we suggest that potyviral HCPro recruits host AGO1 through its WG motif and engages AGO1 in the production of stable virus particles, which are required for an efficient systemic infection.
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Affiliation(s)
- Maija Pollari
- University of Helsinki, Department of Microbiology, Viikki Plant Science Center, Helsinki, Finland
| | - Swarnalok De
- University of Helsinki, Department of Microbiology, Viikki Plant Science Center, Helsinki, Finland
| | - Aiming Wang
- London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario, Canada
| | - Kristiina Mäkinen
- University of Helsinki, Department of Microbiology, Viikki Plant Science Center, Helsinki, Finland
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10
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Nawalpuri B, Ravindran S, Muddashetty RS. The Role of Dynamic miRISC During Neuronal Development. Front Mol Biosci 2020; 7:8. [PMID: 32118035 PMCID: PMC7025485 DOI: 10.3389/fmolb.2020.00008] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2019] [Accepted: 01/10/2020] [Indexed: 12/17/2022] Open
Abstract
Activity-dependent protein synthesis plays an important role during neuronal development by fine-tuning the formation and function of neuronal circuits. Recent studies have shown that miRNAs are integral to this regulation because of their ability to control protein synthesis in a rapid, specific and potentially reversible manner. miRNA mediated regulation is a multistep process that involves inhibition of translation before degradation of targeted mRNA, which provides the possibility to store and reverse the inhibition at multiple stages. This flexibility is primarily thought to be derived from the composition of miRNA induced silencing complex (miRISC). AGO2 is likely the only obligatory component of miRISC, while multiple RBPs are shown to be associated with this core miRISC to form diverse miRISC complexes. The formation of these heterogeneous miRISC complexes is intricately regulated by various extracellular signals and cell-specific contexts. In this review, we discuss the composition of miRISC and its functions during neuronal development. Neurodevelopment is guided by both internal programs and external cues. Neuronal activity and external signals play an important role in the formation and refining of the neuronal network. miRISC composition and diversity have a critical role at distinct stages of neurodevelopment. Even though there is a good amount of literature available on the role of miRNAs mediated regulation of neuronal development, surprisingly the role of miRISC composition and its functional dynamics in neuronal development is not much discussed. In this article, we review the available literature on the heterogeneity of the neuronal miRISC composition and how this may influence translation regulation in the context of neuronal development.
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Affiliation(s)
- Bharti Nawalpuri
- Centre for Brain Development and Repair, Institute for Stem Cell Science and Regenerative Medicine (Instem), Bangalore, India.,School of Chemical and Biotechnology, Shanmugha Arts, Science, and Technology and Research Academy (SASTRA) University, Thanjavur, India
| | - Sreenath Ravindran
- Centre for Brain Development and Repair, Institute for Stem Cell Science and Regenerative Medicine (Instem), Bangalore, India.,Manipal Academy of Higher Education, Manipal, India
| | - Ravi S Muddashetty
- Centre for Brain Development and Repair, Institute for Stem Cell Science and Regenerative Medicine (Instem), Bangalore, India
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11
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Sala L, Chandrasekhar S, Vidigal JA. AGO unchained: Canonical and non-canonical roles of Argonaute proteins in mammals. Front Biosci (Landmark Ed) 2020; 25:1-42. [PMID: 31585876 DOI: 10.2741/4793] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Argonaute (AGO) proteins play key roles in animal physiology by binding to small RNAs and regulating the expression of their targets. In mammals, they do so through two distinct pathways: the miRNA pathway represses genes through a multiprotein complex that promotes both decay and translational repression; the siRNA pathway represses transcripts through direct Ago2-mediated cleavage. Here, we review our current knowledge of mechanistic details and physiological requirements of both these pathways and briefly discuss their implications to human disease.
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Affiliation(s)
- Laura Sala
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, Bethesda, MD 20892, USA
| | - Srividya Chandrasekhar
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, Bethesda, MD 20892, USA
| | - Joana A Vidigal
- Laboratory of Biochemistry and Molecular Biology, National Cancer Institute, Bethesda, MD 20892, USA,
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12
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Zhang R, Jing Y, Zhang H, Niu Y, Liu C, Wang J, Zen K, Zhang CY, Li D. Comprehensive Evolutionary Analysis of the Major RNA-Induced Silencing Complex Members. Sci Rep 2018; 8:14189. [PMID: 30242207 PMCID: PMC6155107 DOI: 10.1038/s41598-018-32635-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 09/12/2018] [Indexed: 01/10/2023] Open
Abstract
RNA-induced silencing complex (RISC) plays a critical role in small interfering RNA (siRNA) and microRNAs (miRNA) pathways. Accumulating evidence has demonstrated that the major RISC members (AGO, DICER, TRBP, PACT and GW182) represent expression discrepancies or multiple orthologues/paralogues in different species. To elucidate their evolutionary characteristics, an integrated evolutionary analysis was performed. Here, animal and plant AGOs were divided into three classes (multifunctional AGOs, siRNA-associated AGOs and piRNA-associated AGOs for animal AGOs and multifunctional AGOs, siRNA-associated AGOs and complementary functioning AGOs for plant AGOs). Animal and plant DICERs were grouped into one class (multifunctional DICERs) and two classes (multifunctional DICERs and siRNA-associated DICERs), respectively. Protista/fungi AGOs or DICERs were specifically associated with the siRNA pathway. Additionally, TRBP/PACT/GW182 were identified only in animals, and all of them functioned in the miRNA pathway. Mammalian AGOs, animal DICERs and chordate TRBP/PACT were found to be monophyletic. A large number of gene duplications were identified in AGO and DICER groups. Taken together, we provide a comprehensive evolutionary analysis, describe a phylogenetic tree-based classification of the major RISC members and quantify their gene duplication events. These findings are potentially useful for classifying RISCs, optimizing species-specific RISCs and developing research model organisms.
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Affiliation(s)
- Rui Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Ying Jing
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Haiyang Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Yahan Niu
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Chang Liu
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Jin Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Ke Zen
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Chen-Yu Zhang
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China
| | - Donghai Li
- State Key Laboratory of Pharmaceutical Biotechnology, Jiangsu Engineering Research Center for MicroRNA Biology and Biotechnology, Nanjing Advanced Institute for Life Sciences (NAILS), School of Life Sciences, Nanjing University, Nanjing, Jiangsu, 210023, P.R. China.
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13
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Role of GW182 protein in the cell. Int J Biochem Cell Biol 2018; 101:29-38. [PMID: 29791863 DOI: 10.1016/j.biocel.2018.05.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 04/23/2018] [Accepted: 05/17/2018] [Indexed: 12/27/2022]
Abstract
GW182 proteins interact directly with the argonaute proteins and constitute key components of miRNA repressor complexes (miRISC) in metazoans. As argonautes are insufficient for silencing they recruit the GW182 s that act as scaffold proteins inducing downstream translational repression, target mRNA deadenylation and exonucleolytic mRNA degradation. Besides their role as part of repressor complexes inside the cell, they function in wide variety of cellular processes as highlighted in this review. The present review summarises and discusses in detail our current knowledge of the GW182 s and their role inside the cell.
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14
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Cieplak-Rotowska MK, Tarnowski K, Rubin M, Fabian MR, Sonenberg N, Dadlez M, Niedzwiecka A. Structural Dynamics of the GW182 Silencing Domain Including its RNA Recognition motif (RRM) Revealed by Hydrogen-Deuterium Exchange Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:158-173. [PMID: 29080206 PMCID: PMC5785596 DOI: 10.1007/s13361-017-1830-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Revised: 09/08/2017] [Accepted: 10/01/2017] [Indexed: 06/07/2023]
Abstract
The human GW182 protein plays an essential role in micro(mi)RNA-dependent gene silencing. miRNA silencing is mediated, in part, by a GW182 C-terminal region called the silencing domain, which interacts with the poly(A) binding protein and the CCR4-NOT deadenylase complex to repress protein synthesis. Structural studies of this GW182 fragment are challenging due to its predicted intrinsically disordered character, except for its RRM domain. However, detailed insights into the properties of proteins containing disordered regions can be provided by hydrogen-deuterium exchange mass spectrometry (HDX/MS). In this work, we applied HDX/MS to define the structural state of the GW182 silencing domain. HDX/MS analysis revealed that this domain is clearly divided into a natively unstructured part, including the CCR4-NOT interacting motif 1, and a distinct RRM domain. The GW182 RRM has a very dynamic structure, since water molecules can penetrate the whole domain in 2 h. The finding of this high structural dynamics sheds new light on the RRM structure. Though this domain is one of the most frequently occurring canonical protein domains in eukaryotes, these results are - to our knowledge - the first HDX/MS characteristics of an RRM. The HDX/MS studies show also that the α2 helix of the RRM can display EX1 behavior after a freezing-thawing cycle. This means that the RRM structure is sensitive to environmental conditions and can change its conformation, which suggests that the state of the RRM containing proteins should be checked by HDX/MS in regard of the conformational uniformity. Graphical Abstract.
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Affiliation(s)
- Maja K Cieplak-Rotowska
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-089, Warsaw, Poland
| | - Krzysztof Tarnowski
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, PL-02106, Warsaw, Poland
| | - Marcin Rubin
- Division of Biophysics, Institute of Experimental Physics, Faculty of Physics, University of Warsaw, 02-089, Warsaw, Poland
| | - Marc R Fabian
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, Québec, Canada
- Department of Oncology, McGill University, Montréal, Québec, Canada
| | - Nahum Sonenberg
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
- Goodman Cancer Center, McGill University, Montréal, Québec, Canada
| | - Michal Dadlez
- Laboratory of Mass Spectrometry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, PL-02106, Warsaw, Poland
| | - Anna Niedzwiecka
- Laboratory of Biological Physics, Institute of Physics, Polish Academy of Sciences, Aleja Lotnikow 32/46, PL-02668, Warsaw, Poland.
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15
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Fontenla S, Rinaldi G, Smircich P, Tort JF. Conservation and diversification of small RNA pathways within flatworms. BMC Evol Biol 2017; 17:215. [PMID: 28893179 PMCID: PMC5594548 DOI: 10.1186/s12862-017-1061-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/05/2017] [Indexed: 02/04/2023] Open
Abstract
Background Small non-coding RNAs, including miRNAs, and gene silencing mediated by RNA interference have been described in free-living and parasitic lineages of flatworms, but only few key factors of the small RNA pathways have been exhaustively investigated in a limited number of species. The availability of flatworm draft genomes and predicted proteomes allowed us to perform an extended survey of the genes involved in small non-coding RNA pathways in this phylum. Results Overall, findings show that the small non-coding RNA pathways are conserved in all the analyzed flatworm linages; however notable peculiarities were identified. While Piwi genes are amplified in free-living worms they are completely absent in all parasitic species. Remarkably all flatworms share a specific Argonaute family (FL-Ago) that has been independently amplified in different lineages. Other key factors such as Dicer are also duplicated, with Dicer-2 showing structural differences between trematodes, cestodes and free-living flatworms. Similarly, a very divergent GW182 Argonaute interacting protein was identified in all flatworm linages. Contrasting to this, genes involved in the amplification of the RNAi interfering signal were detected only in the ancestral free living species Macrostomum lignano. We here described all the putative small RNA pathways present in both free living and parasitic flatworm lineages. Conclusion These findings highlight innovations specifically evolved in platyhelminths presumably associated with novel mechanisms of gene expression regulation mediated by small RNA pathways that differ to what has been classically described in model organisms. Understanding these phylum-specific innovations and the differences between free living and parasitic species might provide clues to adaptations to parasitism, and would be relevant for gene-silencing technology development for parasitic flatworms that infect hundreds of million people worldwide. Electronic supplementary material The online version of this article (10.1186/s12862-017-1061-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Santiago Fontenla
- Departamento de Genética, Facultad de Medicina, Universidad de la República (UDELAR), Gral. Flores 2125, CP11800, Montevideo, MVD, Uruguay
| | - Gabriel Rinaldi
- Parasite Genomics, Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SA, UK
| | - Pablo Smircich
- Departamento de Genética, Facultad de Medicina, Universidad de la República (UDELAR), Gral. Flores 2125, CP11800, Montevideo, MVD, Uruguay.,Laboratorio de Interacciones Moleculares, Facultad de Ciencias, Universidad de la República (UdelaR), Montevideo, Uruguay
| | - Jose F Tort
- Departamento de Genética, Facultad de Medicina, Universidad de la República (UDELAR), Gral. Flores 2125, CP11800, Montevideo, MVD, Uruguay.
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16
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Zielezinski A, Karlowski WM. Identification and Analysis of WG/GW ARGONAUTE-Binding Domains. Methods Mol Biol 2017; 1640:241-256. [PMID: 28608348 DOI: 10.1007/978-1-4939-7165-7_18] [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: 06/07/2023]
Abstract
WG/GW domains recruit ARGONAUTE (AGO) proteins to distinct silencing effector complexes using combinations of just two amino acids: tryptophan (W) and glycine (G), forming a wide arsenal of highly simplified interaction surfaces. These unstructured domains exhibit very low sequence identity and excessive length polymorphism, which makes identification of new AGO-binding proteins a challenging task as they escape detection with standard sequence comparison-based methods (e.g., BLAST, HMMER).In this chapter, we explain the use of tools for prediction of AGO-binding WG/GW domains in protein sequences. We also show how to computationally explore an up-to-date information about AGO-interacting proteins and discover new properties of WG/GW domains. Finally, we encourage readers to explore the game-like web application for in silico designing/modifying AGO-binding sequences as well as modeling mutagenesis experiments and predicting their potential effect on AGO-binding activity.
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Affiliation(s)
- Andrzej Zielezinski
- Department of Computational Biology, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Umultowska 89, 61-614, Poznan, Poland
| | - Wojciech M Karlowski
- Department of Computational Biology, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Umultowska 89, 61-614, Poznan, Poland.
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17
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Flamand MN, Wu E, Vashisht A, Jannot G, Keiper BD, Simard MJ, Wohlschlegel J, Duchaine TF. Poly(A)-binding proteins are required for microRNA-mediated silencing and to promote target deadenylation in C. elegans. Nucleic Acids Res 2016; 44:5924-35. [PMID: 27095199 PMCID: PMC4937315 DOI: 10.1093/nar/gkw276] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 04/04/2016] [Accepted: 04/06/2016] [Indexed: 01/08/2023] Open
Abstract
Cytoplasmic poly(A)-binding proteins (PABPs) link mRNA 3' termini to translation initiation factors, but they also play key roles in mRNA regulation and decay. Reports from mice, zebrafish and Drosophila further involved PABPs in microRNA (miRNA)-mediated silencing, but through seemingly distinct mechanisms. Here, we implicate the two Caenorhabditis elegans PABPs (PAB-1 and PAB-2) in miRNA-mediated silencing, and elucidate their mechanisms of action using concerted genetics, protein interaction analyses, and cell-free assays. We find that C. elegans PABPs are required for miRNA-mediated silencing in embryonic and larval developmental stages, where they act through a multi-faceted mechanism. Depletion of PAB-1 and PAB-2 results in loss of both poly(A)-dependent and -independent translational silencing. PABPs accelerate miRNA-mediated deadenylation, but this contribution can be modulated by 3'UTR sequences. While greater distances with the poly(A) tail exacerbate dependency on PABP for deadenylation, more potent miRNA-binding sites partially suppress this effect. Our results refine the roles of PABPs in miRNA-mediated silencing and support a model wherein they enable miRNA-binding sites by looping the 3'UTR poly(A) tail to the bound miRISC and deadenylase.
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Affiliation(s)
- Mathieu N Flamand
- Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
| | - Edlyn Wu
- Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada Division of Experimental Medicine & Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
| | - Ajay Vashisht
- Department of Biological Chemistry David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Guillaume Jannot
- St-Patrick Research Group in Basic Oncology, Centre Hospitalier Universitaire de Québec-Université Laval (Hôtel-Dieu de Québec), Laval University Cancer Research Centre, Quebec City, QC G1R 2J6, Canada
| | - Brett D Keiper
- Department of Biochemistry and Molecular Biology, Brody School of Medicine at East Carolina University, Greenville, NC 27834, USA
| | - Martin J Simard
- St-Patrick Research Group in Basic Oncology, Centre Hospitalier Universitaire de Québec-Université Laval (Hôtel-Dieu de Québec), Laval University Cancer Research Centre, Quebec City, QC G1R 2J6, Canada
| | - James Wohlschlegel
- Department of Biological Chemistry David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Thomas F Duchaine
- Department of Biochemistry, McGill University, Montreal, QC H3A 1A3, Canada Division of Experimental Medicine & Goodman Cancer Research Center, McGill University, Montreal, QC H3A 1A3, Canada
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