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Yamagishi R, Inagaki H, Suzuki J, Hosoda N, Sugiyama H, Tomita K, Hotta T, Hoshino SI. Concerted action of ataxin-2 and PABPC1-bound mRNA poly(A) tail in the formation of stress granules. Nucleic Acids Res 2024; 52:9193-9209. [PMID: 38869059 PMCID: PMC11347130 DOI: 10.1093/nar/gkae497] [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: 09/25/2023] [Revised: 05/24/2024] [Accepted: 05/29/2024] [Indexed: 06/14/2024] Open
Abstract
Stress induces global stabilization of the mRNA poly(A) tail (PAT) and the assembly of untranslated poly(A)-tailed mRNA into mRNPs that accumulate in stress granules (SGs). While the mechanism behind stress-induced global PAT stabilization has recently emerged, the biological significance of PAT stabilization under stress remains elusive. Here, we demonstrate that stress-induced PAT stabilization is a prerequisite for SG formation. Perturbations in PAT length impact SG formation; PAT shortening, achieved by overexpressing mRNA deadenylases, inhibits SG formation, whereas PAT lengthening, achieved by overexpressing their dominant negative mutants or downregulating deadenylases, promotes it. PABPC1, which specifically binds to the PAT, is crucial for SG formation. Complementation analyses reveal that the PABC/MLLE domain of PABPC1, responsible for binding PAM2 motif-containing proteins, plays a key role. Among them, ataxin-2 is a known SG component. A dominant-negative approach reveals that the PAM2 motif of ataxin-2 is essential for SG formation. Notably, ataxin-2 increases stress sensitivity, lowering the threshold for SG formation, probably by promoting the aggregation of PABPC1-bound mRNA. The C-terminal region is responsible for the self-aggregation of ataxin-2. These findings underscore the critical roles of mRNA PAT, PABPC1 and ataxin-2 in SG formation and provide mechanistic insights into this process.
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Affiliation(s)
- Ryota Yamagishi
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Hiroto Inagaki
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Jun Suzuki
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Nao Hosoda
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Haruka Sugiyama
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Kazunori Tomita
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Takashi Hotta
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Shin-ichi Hoshino
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
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2
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Li L, Wang M, Huang L, Zheng X, Wang L, Miao H. Ataxin-2: a powerful RNA-binding protein. Discov Oncol 2024; 15:298. [PMID: 39039334 PMCID: PMC11263328 DOI: 10.1007/s12672-024-01158-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 07/15/2024] [Indexed: 07/24/2024] Open
Abstract
Ataxin-2 (ATXN2) was originally discovered in the context of spinocerebellar ataxia type 2 (SCA2), but it has become a key player in various neurodegenerative diseases. This review delves into the multifaceted roles of ATXN2 in human diseases, revealing its diverse molecular and cellular pathways. The impact of ATXN2 on diseases extends beyond functional outcomes; it mainly interacts with various RNA-binding proteins (RBPs) to regulate different stages of post-transcriptional gene expression in diseases. With the progress of research, ATXN2 has also been found to play an important role in the development of various cancers, including breast cancer, gastric cancer, pancreatic cancer, colon cancer, and esophageal cancer. This comprehensive exploration underscores the crucial role of ATXN2 in the pathogenesis of diseases and warrants further investigation by the scientific community. By reviewing the latest discoveries on the regulatory functions of ATXN2 in diseases, this article helps us understand the complex molecular mechanisms of a series of human diseases related to this intriguing protein.
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Affiliation(s)
- Lulu Li
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, China
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, China
| | - Meng Wang
- Department of Pathophysiology, College of High Altitude Military Medicine, Army Medical University, Chongqing, 400038, China
| | - Lai Huang
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, China
| | - Xiaoli Zheng
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, China.
| | - Lina Wang
- Department of Clinical and Military Laboratory Medicine, College of Medical Laboratory Science, Army Medical University, Chongqing, 400038, China.
| | - Hongming Miao
- Department of Pathophysiology, College of High Altitude Military Medicine, Army Medical University, Chongqing, 400038, China.
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3
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Wang JY, Liu YJ, Zhang XL, Liu YH, Jiang LL, Hu HY. PolyQ-expanded ataxin-2 aggregation impairs cellular processing-body homeostasis via sequestering the RNA helicase DDX6. J Biol Chem 2024; 300:107413. [PMID: 38810698 PMCID: PMC11254730 DOI: 10.1016/j.jbc.2024.107413] [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: 01/09/2024] [Revised: 04/02/2024] [Accepted: 04/10/2024] [Indexed: 05/31/2024] Open
Abstract
Ataxin-2 (Atx2) is a polyglutamine (polyQ) tract-containing RNA-binding protein, while its polyQ expansion may cause protein aggregation that is implicated in the pathogenesis of neurodegenerative diseases such as spinocerebellar ataxia type 2 (SCA2). However, the molecular mechanism underlying how Atx2 aggregation contributes to the proteinopathies remains elusive. Here, we investigated the influence of Atx2 aggregation on the assembly and functionality of cellular processing bodies (P-bodies) by using biochemical and fluorescence imaging approaches. We have revealed that polyQ-expanded (PQE) Atx2 sequesters the DEAD-box RNA helicase (DDX6), an essential component of P-bodies, into aggregates or puncta via some RNA sequences. The N-terminal like-Sm (LSm) domain of Atx2 (residues 82-184) and the C-terminal helicase domain of DDX6 are responsible for the interaction and specific sequestration. Moreover, sequestration of DDX6 may aggravate pre-mRNA mis-splicing, and interfere with the assembly of cellular P-bodies, releasing the endoribonuclease MARF1 that promotes mRNA decay and translational repression. Rescuing the DDX6 protein level can recover the assembly and functionality of P-bodies, preventing targeted mRNA from degradation. This study provides a line of evidence for sequestration of the P-body components and impairment of the P-body homeostasis in dysregulating RNA metabolism, which is implicated in the disease pathologies and a potential therapeutic target.
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Affiliation(s)
- Jian-Yang Wang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, PR China; University of Chinese Academy of Sciences, Beijing, PR China
| | - Ya-Jun Liu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, PR China; University of Chinese Academy of Sciences, Beijing, PR China
| | - Xiang-Le Zhang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, PR China; University of Chinese Academy of Sciences, Beijing, PR China
| | - Yin-Hu Liu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, PR China; University of Chinese Academy of Sciences, Beijing, PR China
| | - Lei-Lei Jiang
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, PR China
| | - Hong-Yu Hu
- State Key Laboratory of Molecular Biology, Shanghai Institute of Biochemistry and Cell Biology, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences, Shanghai, PR China.
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4
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Bonsor M, Ammar O, Schnoegl S, Wanker EE, Silva Ramos E. Polyglutamine disease proteins: Commonalities and differences in interaction profiles and pathological effects. Proteomics 2024; 24:e2300114. [PMID: 38615323 DOI: 10.1002/pmic.202300114] [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: 11/30/2023] [Revised: 03/25/2024] [Accepted: 03/27/2024] [Indexed: 04/16/2024]
Abstract
Currently, nine polyglutamine (polyQ) expansion diseases are known. They include spinocerebellar ataxias (SCA1, 2, 3, 6, 7, 17), spinal and bulbar muscular atrophy (SBMA), dentatorubral-pallidoluysian atrophy (DRPLA), and Huntington's disease (HD). At the root of these neurodegenerative diseases are trinucleotide repeat mutations in coding regions of different genes, which lead to the production of proteins with elongated polyQ tracts. While the causative proteins differ in structure and molecular mass, the expanded polyQ domains drive pathogenesis in all these diseases. PolyQ tracts mediate the association of proteins leading to the formation of protein complexes involved in gene expression regulation, RNA processing, membrane trafficking, and signal transduction. In this review, we discuss commonalities and differences among the nine polyQ proteins focusing on their structure and function as well as the pathological features of the respective diseases. We present insights from AlphaFold-predicted structural models and discuss the biological roles of polyQ-containing proteins. Lastly, we explore reported protein-protein interaction networks to highlight shared protein interactions and their potential relevance in disease development.
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Affiliation(s)
- Megan Bonsor
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Orchid Ammar
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Sigrid Schnoegl
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Erich E Wanker
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Eduardo Silva Ramos
- Department of Neuroproteomics, Max Delbrück Center for Molecular Medicine, Berlin, Germany
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5
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Petrauskas A, Fortunati DL, Kandi AR, Pothapragada SS, Agrawal K, Singh A, Huelsmeier J, Hillebrand J, Brown G, Chaturvedi D, Lee J, Lim C, Auburger G, VijayRaghavan K, Ramaswami M, Bakthavachalu B. Structured and disordered regions of Ataxin-2 contribute differently to the specificity and efficiency of mRNP granule formation. PLoS Genet 2024; 20:e1011251. [PMID: 38768217 PMCID: PMC11166328 DOI: 10.1371/journal.pgen.1011251] [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: 01/27/2024] [Revised: 06/11/2024] [Accepted: 04/05/2024] [Indexed: 05/22/2024] Open
Abstract
Ataxin-2 (ATXN2) is a gene implicated in spinocerebellar ataxia type II (SCA2), amyotrophic lateral sclerosis (ALS) and Parkinsonism. The encoded protein is a therapeutic target for ALS and related conditions. ATXN2 (or Atx2 in insects) can function in translational activation, translational repression, mRNA stability and in the assembly of mRNP-granules, a process mediated by intrinsically disordered regions (IDRs). Previous work has shown that the LSm (Like-Sm) domain of Atx2, which can help stimulate mRNA translation, antagonizes mRNP-granule assembly. Here we advance these findings through a series of experiments on Drosophila and human Ataxin-2 proteins. Results of Targets of RNA Binding Proteins Identified by Editing (TRIBE), co-localization and immunoprecipitation experiments indicate that a polyA-binding protein (PABP) interacting, PAM2 motif of Ataxin-2 may be a major determinant of the mRNA and protein content of Ataxin-2 mRNP granules. Experiments with transgenic Drosophila indicate that while the Atx2-LSm domain may protect against neurodegeneration, structured PAM2- and unstructured IDR- interactions both support Atx2-induced cytotoxicity. Taken together, the data lead to a proposal for how Ataxin-2 interactions are remodelled during translational control and how structured and non-structured interactions contribute differently to the specificity and efficiency of RNP granule condensation as well as to neurodegeneration.
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Affiliation(s)
- Arnas Petrauskas
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Daniel L. Fortunati
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Arvind Reddy Kandi
- School of Biosciences and Bioengineering, Indian Institute of Technology, Mandi, India
| | | | - Khushboo Agrawal
- Tata Institute for Genetics and Society Centre at inStem, Bellary Road, Bangalore, India
- School of Biotechnology, Amrita Vishwa Vidyapeetham University, Kollam, Kerala, India
| | - Amanjot Singh
- National Centre for Biological Sciences, TIFR, Bangalore, India
- Manipal Institute of Regenerative Medicine, MAHE-Bengaluru, Govindapura, Bengaluru, India
| | - Joern Huelsmeier
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Jens Hillebrand
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | - Georgia Brown
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
| | | | - Jongbo Lee
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan, Republic of Korea
| | - Chunghun Lim
- Department of Biological Sciences, Ulsan National Institute of Science and Technology (UNIST), 50 UNIST-gil, Ulsan, Republic of Korea
| | - Georg Auburger
- Experimental Neurology, Medical School, Goethe University, Frankfurt, Germany
| | | | - Mani Ramaswami
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College Dublin, Dublin, Ireland
- National Centre for Biological Sciences, TIFR, Bangalore, India
| | - Baskar Bakthavachalu
- School of Biosciences and Bioengineering, Indian Institute of Technology, Mandi, India
- Tata Institute for Genetics and Society Centre at inStem, Bellary Road, Bangalore, India
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6
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Chitre M, Emery P. ATXN2 is a target of N-terminal proteolysis. PLoS One 2023; 18:e0296085. [PMID: 38128014 PMCID: PMC10735043 DOI: 10.1371/journal.pone.0296085] [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: 10/11/2023] [Accepted: 12/04/2023] [Indexed: 12/23/2023] Open
Abstract
Spinocerebellar ataxia 2 (SCA2) is a neurodegenerative disorder caused by the expansion of the poly-glutamine (polyQ) tract of Ataxin-2 (ATXN2). Other polyQ-containing proteins such as ATXN7 and huntingtin are associated with the development of neurodegenerative diseases when their N-terminal polyQ domains are expanded. Furthermore, they undergo proteolytic processing events that produce N-terminal fragments that include the polyQ stretch, which are implicated in pathogenesis. Interestingly, N-terminal ATXN2 fragments were reported in a brain extract from a SCA2 patient, but it is currently unknown whether an expanded polyQ domain contributes to ATXN2 proteolytic susceptibility. Here, we used transient expression in HEK293 cells to determine whether ATXN2 is a target for specific N-terminal proteolysis. We found that ATXN2 proteins with either normal or expanded polyQ stretches undergo proteolytic cleavage releasing an N-terminal polyQ-containing fragment. We identified a short amino acid sequence downstream of the polyQ domain that is necessary for N-terminal cleavage of full-length ATXN2 and sufficient to induce proteolysis of a heterologous protein. However, this sequence is not required for cleavage of a short ATXN2 isoform produced from an alternative start codon located just upstream of the CAG repeats encoding the polyQ domain. Our study extends our understanding of ATXN2 posttranslational regulation by revealing that this protein can be the target of specific proteolytic cleavage events releasing polyQ-containing products that are modulated by the N-terminal domain of ATXN2. N-terminal ATXN2 proteolysis of expanded polyQ domains might contribute to SCA2 pathology, as observed in other neurodegenerative disorders caused by polyQ domain expansion.
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Affiliation(s)
- Monika Chitre
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
- Interdisciplinary Graduate Program, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
| | - Patrick Emery
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
- Interdisciplinary Graduate Program, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Chan Medical School, Worcester, Massachusetts, United States of America
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7
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Ogami K, Ogawa K, Sanpei S, Ichikawa F, Udagawa T, Hoshino SI. A Combinatorial Code for CPEB-Mediated c-myc Repression. Cells 2023; 12:2410. [PMID: 37830624 PMCID: PMC10572585 DOI: 10.3390/cells12192410] [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: 05/12/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/14/2023] Open
Abstract
During early embryonic development, the RNA-binding protein CPEB mediates cytoplasmic polyadenylation and translational activation through a combinatorial code defined by the cy-toplasmic polyadenylation element (CPE) present in maternal mRNAs. However, in non-neuronal somatic cells, CPEB accelerates deadenylation to repress translation of the target, including c-myc mRNA, through an ill-defined cis-regulatory mechanism. Using RNA mutagenesis and electrophoretic mobility shift assays, we demonstrated that a combination of tandemly arranged consensus (cCPE) and non-consensus (ncCPE) cytoplasmic polyadenylation elements (CPEs) constituted a combinatorial code for CPEB-mediated c-myc mRNA decay. CPEB binds to cCPEs with high affinity (Kd = ~250 nM), whereas it binds to ncCPEs with low affinity (Kd > ~900 nM). CPEB binding to a cCPE enhances CPEB binding to the proximal ncCPE. In contrast, while a cCPE did not activate mRNA degradation, an ncCPE was essential for the induction of degradation, and a combination of a cCPE and ncCPEs further promoted degradation. Based on these findings, we propose a model in which the high-affinity binding of CPEB to the cCPE accelerates the binding of the second CPEB to the ncCPEs, resulting in the recruitment of deadenylases, acceleration of deadenylation, and repression of c-myc mRNAs.
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Affiliation(s)
- Koichi Ogami
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan (F.I.); (T.U.)
- Division of Molecular Oncology, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, Nagoya 466-8550, Japan
| | - Keima Ogawa
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan (F.I.); (T.U.)
| | - Shoko Sanpei
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan (F.I.); (T.U.)
| | - Fumito Ichikawa
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan (F.I.); (T.U.)
| | - Tsuyoshi Udagawa
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan (F.I.); (T.U.)
| | - Shin-ichi Hoshino
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan (F.I.); (T.U.)
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8
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Zhuang Y, Li Z, Xiong S, Sun C, Li B, Wu SA, Lyu J, Shi X, Yang L, Chen Y, Bao Z, Li X, Sun C, Chen Y, Deng H, Li T, Wu Q, Qi L, Huang Y, Yang X, Lin Y. Circadian clocks are modulated by compartmentalized oscillating translation. Cell 2023; 186:3245-3260.e23. [PMID: 37369203 DOI: 10.1016/j.cell.2023.05.045] [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: 12/12/2022] [Revised: 04/12/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023]
Abstract
Terrestrial organisms developed circadian rhythms for adaptation to Earth's quasi-24-h rotation. Achieving precise rhythms requires diurnal oscillation of fundamental biological processes, such as rhythmic shifts in the cellular translational landscape; however, regulatory mechanisms underlying rhythmic translation remain elusive. Here, we identified mammalian ATXN2 and ATXN2L as cooperating master regulators of rhythmic translation, through oscillating phase separation in the suprachiasmatic nucleus along circadian cycles. The spatiotemporal oscillating condensates facilitate sequential initiation of multiple cycling processes, from mRNA processing to protein translation, for selective genes including core clock genes. Depleting ATXN2 or 2L induces opposite alterations to the circadian period, whereas the absence of both disrupts translational activation cycles and weakens circadian rhythmicity in mice. Such cellular defect can be rescued by wild type, but not phase-separation-defective ATXN2. Together, we revealed that oscillating translation is regulated by spatiotemporal condensation of two master regulators to achieve precise circadian rhythm in mammals.
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Affiliation(s)
- Yanrong Zhuang
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhiyuan Li
- School of Life Sciences, MOE Key Laboratory of Bioinformatics, Center for Synthetic & Systems Biology, Tsinghua University, Beijing 100084, China
| | - Shiyue Xiong
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Chujie Sun
- School of Life Sciences, MOE Key Laboratory of Bioinformatics, Center for Synthetic & Systems Biology, Tsinghua University, Beijing 100084, China
| | - Boya Li
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Shuangcheng Alivia Wu
- Department of Molecular & Integrative Physiology, Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Jiali Lyu
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xiang Shi
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Liang Yang
- Department of Medical Bioinformatics, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission of China, Peking University, Beijing 100191, China
| | - Yutong Chen
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhangbin Bao
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xi Li
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Chuhanwen Sun
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yuling Chen
- School of Life Sciences, MOE Key Laboratory of Bioinformatics, Center for Synthetic & Systems Biology, Tsinghua University, Beijing 100084, China
| | - Haiteng Deng
- School of Life Sciences, MOE Key Laboratory of Bioinformatics, Center for Synthetic & Systems Biology, Tsinghua University, Beijing 100084, China
| | - Tingting Li
- Department of Medical Bioinformatics, School of Basic Medical Sciences, Key Laboratory for Neuroscience, Ministry of Education, National Health Commission of China, Peking University, Beijing 100191, China
| | - Qingfeng Wu
- State Key Laboratory of Molecular Development Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China
| | - Ling Qi
- Department of Molecular & Integrative Physiology, Division of Metabolism, Endocrinology & Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Yue Huang
- China National Clinical Research Center for Neurological Diseases and Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Beijing 100050, China; Phamalology Department, School of Biomedical Sciences, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Xuerui Yang
- School of Life Sciences, MOE Key Laboratory of Bioinformatics, Center for Synthetic & Systems Biology, Tsinghua University, Beijing 100084, China.
| | - Yi Lin
- State Key Laboratory of Membrane Biology, IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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9
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Boeynaems S, Dorone Y, Zhuang Y, Shabardina V, Huang G, Marian A, Kim G, Sanyal A, Şen NE, Griffith D, Docampo R, Lasker K, Ruiz-Trillo I, Auburger G, Holehouse AS, Kabashi E, Lin Y, Gitler AD. Poly(A)-binding protein is an ataxin-2 chaperone that regulates biomolecular condensates. Mol Cell 2023; 83:2020-2034.e6. [PMID: 37295429 PMCID: PMC10318123 DOI: 10.1016/j.molcel.2023.05.025] [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: 08/23/2021] [Revised: 03/14/2023] [Accepted: 05/17/2023] [Indexed: 06/12/2023]
Abstract
Biomolecular condensation underlies the biogenesis of an expanding array of membraneless assemblies, including stress granules (SGs), which form under a variety of cellular stresses. Advances have been made in understanding the molecular grammar of a few scaffold proteins that make up these phases, but how the partitioning of hundreds of SG proteins is regulated remains largely unresolved. While investigating the rules that govern the condensation of ataxin-2, an SG protein implicated in neurodegenerative disease, we unexpectedly identified a short 14 aa sequence that acts as a condensation switch and is conserved across the eukaryote lineage. We identify poly(A)-binding proteins as unconventional RNA-dependent chaperones that control this regulatory switch. Our results uncover a hierarchy of cis and trans interactions that fine-tune ataxin-2 condensation and reveal an unexpected molecular function for ancient poly(A)-binding proteins as regulators of biomolecular condensate proteins. These findings may inspire approaches to therapeutically target aberrant phases in disease.
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Affiliation(s)
- Steven Boeynaems
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Therapeutic Innovation Center (THINC), Baylor College of Medicine, Houston, TX 77030, USA; Center for Alzheimer's and Neurodegenerative Diseases (CAND), Texas Children's Hospital, Houston, TX 77030, USA; Dan L Duncan Comprehensive Cancer Center (DLDCCC), Baylor College of Medicine, Houston, TX 77030, USA; Department of Genetics, Stanford University, Stanford, CA 94305, USA.
| | - Yanniv Dorone
- Department of Plant Biology, Carnegie Institution for Science, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Yanrong Zhuang
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Victoria Shabardina
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003 Catalonia, Spain
| | - Guozhong Huang
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Anca Marian
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France
| | - Garam Kim
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Anushka Sanyal
- Department of Genetics, Stanford University, Stanford, CA 94305, USA
| | - Nesli-Ece Şen
- Experimental Neurology, Goethe-University Hospital, 60590 Frankfurt, Germany
| | - Daniel Griffith
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Biomolecular Condensates, Washington University in St Louis, St. Louis, MO 63130, USA
| | - Roberto Docampo
- Department of Cellular Biology and Center for Tropical and Emerging Global Diseases, University of Georgia, Athens, GA 30602, USA
| | - Keren Lasker
- The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Iñaki Ruiz-Trillo
- Institut de Biologia Evolutiva (CSIC-Universitat Pompeu Fabra), Passeig Marítim de la Barceloneta 37-49, Barcelona 08003 Catalonia, Spain; ICREA, Passeig Lluís Companys 23, Barcelona 08010 Catalonia, Spain
| | - Georg Auburger
- Experimental Neurology, Goethe-University Hospital, 60590 Frankfurt, Germany
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA; Center for Biomolecular Condensates, Washington University in St Louis, St. Louis, MO 63130, USA
| | - Edor Kabashi
- Imagine Institute, Institut National de la Santé et de la Recherche Médicale (INSERM) Unité 1163, Paris Descartes Université, 75015 Paris, France
| | - Yi Lin
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Joint Centre for Life Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Aaron D Gitler
- Department of Genetics, Stanford University, Stanford, CA 94305, USA; Chan Zuckerberg Biohub, San Francisco, CA 94158, USA.
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10
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Koppenol R, Conceição A, Afonso IT, Afonso-Reis R, Costa RG, Tomé S, Teixeira D, da Silva JP, Côdesso JM, Brito DVC, Mendonça L, Marcelo A, Pereira de Almeida L, Matos CA, Nóbrega C. The stress granule protein G3BP1 alleviates spinocerebellar ataxia-associated deficits. Brain 2023; 146:2346-2363. [PMID: 36511898 PMCID: PMC10232246 DOI: 10.1093/brain/awac473] [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] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 11/04/2022] [Accepted: 11/25/2022] [Indexed: 09/09/2023] Open
Abstract
Polyglutamine diseases are a group of neurodegenerative disorders caused by an abnormal expansion of CAG repeat tracts in the codifying regions of nine, otherwise unrelated, genes. While the protein products of these genes are suggested to play diverse cellular roles, the pathogenic mutant proteins bearing an expanded polyglutamine sequence share a tendency to self-assemble, aggregate and engage in abnormal molecular interactions. Understanding the shared paths that link polyglutamine protein expansion to the nervous system dysfunction and the degeneration that takes place in these disorders is instrumental to the identification of targets for therapeutic intervention. Among polyglutamine diseases, spinocerebellar ataxias (SCAs) share many common aspects, including the fact that they involve dysfunction of the cerebellum, resulting in ataxia. Our work aimed at exploring a putative new therapeutic target for the two forms of SCA with higher worldwide prevalence, SCA type 2 (SCA2) and type 3 (SCA3), which are caused by expanded forms of ataxin-2 (ATXN2) and ataxin-3 (ATXN3), respectively. The pathophysiology of polyglutamine diseases has been described to involve an inability to properly respond to cell stress. We evaluated the ability of GTPase-activating protein-binding protein 1 (G3BP1), an RNA-binding protein involved in RNA metabolism regulation and stress responses, to counteract SCA2 and SCA3 pathology, using both in vitro and in vivo disease models. Our results indicate that G3BP1 overexpression in cell models leads to a reduction of ATXN2 and ATXN3 aggregation, associated with a decrease in protein expression. This protective effect of G3BP1 against polyglutamine protein aggregation was reinforced by the fact that silencing G3bp1 in the mouse brain increases human expanded ATXN2 and ATXN3 aggregation. Moreover, a decrease of G3BP1 levels was detected in cells derived from patients with SCA2 and SCA3, suggesting that G3BP1 function is compromised in the context of these diseases. In lentiviral mouse models of SCA2 and SCA3, G3BP1 overexpression not only decreased protein aggregation but also contributed to the preservation of neuronal cells. Finally, in an SCA3 transgenic mouse model with a severe ataxic phenotype, G3BP1 lentiviral delivery to the cerebellum led to amelioration of several motor behavioural deficits. Overall, our results indicate that a decrease in G3BP1 levels may be a contributing factor to SCA2 and SCA3 pathophysiology, and that administration of this protein through viral vector-mediated delivery may constitute a putative approach to therapy for these diseases, and possibly other polyglutamine disorders.
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Affiliation(s)
- Rebekah Koppenol
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- PhD Program in Biomedial Sciences, Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
| | - André Conceição
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- PhD Program in Biomedial Sciences, Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Inês T Afonso
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Ricardo Afonso-Reis
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Rafael G Costa
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Sandra Tomé
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Diogo Teixeira
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
| | | | - José Miguel Côdesso
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- PhD Program in Biomedial Sciences, Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
| | - David V C Brito
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
| | - Liliana Mendonça
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Adriana Marcelo
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
| | - Luís Pereira de Almeida
- Center for Neuroscience and Cell Biology (CNC), University of Coimbra, 3004-504 Coimbra, Portugal
- Faculty of Pharmacy, University of Coimbra, 3000-548 Coimbra, Portugal
| | - Carlos A Matos
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
| | - Clévio Nóbrega
- ABC-RI, Algarve Biomedical Center Research Institute, 8005-139 Faro, Portugal
- Faculdade de Medicina e Ciências Biomédicas, Universidade do Algarve, 8005-139 Faro, Portugal
- Champalimaud Research Program, Champalimaud Center for the Unknown, 1400-038 Lisbon, Portugal
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11
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Turner M. Regulation and function of poised mRNAs in lymphocytes. Bioessays 2023; 45:e2200236. [PMID: 37009769 DOI: 10.1002/bies.202200236] [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: 12/07/2022] [Revised: 02/15/2023] [Accepted: 02/17/2023] [Indexed: 04/04/2023]
Abstract
Pre-existing but untranslated or 'poised' mRNA exists as a means to rapidly induce the production of specific proteins in response to stimuli and as a safeguard to limit the actions of these proteins. The translation of poised mRNA enables immune cells to express quickly genes that enhance immune responses. The molecular mechanisms that repress the translation of poised mRNA and, upon stimulation, enable translation have yet to be elucidated. They likely reflect intrinsic properties of the mRNAs and their interactions with trans-acting factors that direct poised mRNAs away from or into the ribosome. Here, I discuss mechanisms by which this might be regulated.
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Affiliation(s)
- Martin Turner
- Immunology Programme, The Babraham Institute, Cambridge, UK
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12
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Wijegunawardana D, Vishal SS, Venkatesh N, Gopal PP. Ataxin-2 polyglutamine expansions aberrantly sequester TDP-43, drive ribonucleoprotein condensate transport dysfunction and suppress local translation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.30.526372. [PMID: 36778347 PMCID: PMC9915502 DOI: 10.1101/2023.01.30.526372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Altered RNA metabolism is a common pathogenic mechanism linked to familial and sporadic Amyotrophic lateral sclerosis (ALS). ALS is characterized by mislocalization and aggregation of TDP-43, an RNA-binding protein (RBP) with multiple roles in post-transcriptional RNA processing. Recent studies have identified genetic interactions between TDP-43 and Ataxin-2, a polyglutamine (polyQ) RBP in which intermediate length polyQ expansions confer increased ALS risk. Here, we used live-cell confocal imaging, photobleaching and translation reporter assays to study the localization, transport dynamics and mRNA regulatory functions of TDP-43/Ataxin-2 in rodent primary cortical neurons. We show that Ataxin-2 polyQ expansions aberrantly sequester TDP-43 within ribonucleoprotein (RNP) condensates, and disrupt both its motility along the axon and liquid-like properties. Our data suggest that Ataxin-2 governs motility and translation of neuronal RNP condensates and that Ataxin-2 polyQ expansions fundamentally perturb spatial localization of mRNA and suppress local translation. Overall, these results indicate Ataxin-2 polyQ expansions have detrimental effects on stability, localization, and translation of transcripts critical for axonal and cytoskeletal integrity, particularly important for motor neurons.
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13
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Nadimpalli HP, Guitart T, Coll O, Gebauer F. Ataxin-2, Twenty-four, and Dicer-2 are components of a noncanonical cytoplasmic polyadenylation complex. Life Sci Alliance 2022; 5:5/12/e202201417. [PMID: 36114004 PMCID: PMC9481931 DOI: 10.26508/lsa.202201417] [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: 02/18/2022] [Revised: 09/05/2022] [Accepted: 09/06/2022] [Indexed: 11/26/2022] Open
Abstract
Identification of components of a noncanonical cytoplasmic polyadenylation machinery in Drosophila expands the diversity of RNA-binding proteins involved in poly(A) tail length control. Cytoplasmic polyadenylation is a mechanism to promote mRNA translation in a wide variety of biological contexts. A canonical complex centered around the conserved RNA-binding protein family CPEB has been shown to be responsible for this process. We have previously reported evidence for an alternative noncanonical, CPEB-independent complex in Drosophila, of which the RNA-interference factor Dicer-2 is a component. Here, we investigate Dicer-2 mRNA targets and protein cofactors in cytoplasmic polyadenylation. Using RIP-Seq analysis, we identify hundreds of potential Dicer-2 target transcripts, ∼60% of which were previously found as targets of the cytoplasmic poly(A) polymerase Wispy, suggesting widespread roles of Dicer-2 in cytoplasmic polyadenylation. Large-scale immunoprecipitation revealed Ataxin-2 and Twenty-four among the high-confidence interactors of Dicer-2. Complex analyses indicated that both factors form an RNA-independent complex with Dicer-2 and mediate interactions of Dicer-2 with Wispy. Functional poly(A)-test analyses showed that Twenty-four and Ataxin-2 are required for cytoplasmic polyadenylation of a subset of Dicer-2 targets. Our results reveal components of a novel cytoplasmic polyadenylation complex that operates during Drosophila early embryogenesis.
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Affiliation(s)
- Hima Priyanka Nadimpalli
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Tanit Guitart
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Olga Coll
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Fátima Gebauer
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona, Spain
- University of Pompeu Fabra (UPF), Barcelona, Spain
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14
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Qi Y, Wang M, Jiang Q. PABPC1--mRNA stability, protein translation and tumorigenesis. Front Oncol 2022; 12:1025291. [PMID: 36531055 PMCID: PMC9753129 DOI: 10.3389/fonc.2022.1025291] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Accepted: 11/08/2022] [Indexed: 09/29/2023] Open
Abstract
Mammalian poly A-binding proteins (PABPs) are highly conserved multifunctional RNA-binding proteins primarily involved in the regulation of mRNA translation and stability, of which PABPC1 is considered a central regulator of cytoplasmic mRNA homing and is involved in a wide range of physiological and pathological processes by regulating almost every aspect of RNA metabolism. Alterations in its expression and function disrupt intra-tissue homeostasis and contribute to the development of various tumors. There is increasing evidence that PABPC1 is aberrantly expressed in a variety of tumor tissues and cancers such as lung, gastric, breast, liver, and esophageal cancers, and PABPC1 might be used as a potential biomarker for tumor diagnosis, treatment, and clinical application in the future. In this paper, we review the abnormal expression, functional role, and molecular mechanism of PABPC1 in tumorigenesis and provide directions for further understanding the regulatory role of PABPC1 in tumor cells.
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Affiliation(s)
- Ya Qi
- Department of Gynecology and Obstetrics, Shengjing Hospital Affiliated of China Medical University, Shenyang, Liaoning, China
| | - Min Wang
- Department of Gynecology and Obstetrics, Shengjing Hospital Affiliated of China Medical University, Shenyang, Liaoning, China
| | - Qi Jiang
- Second Department of Clinical Medicine, China Medical University, Shenyang, Liaoning, China
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15
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mTOR- and LARP1-dependent regulation of TOP mRNA poly(A) tail and ribosome loading. Cell Rep 2022; 41:111548. [DOI: 10.1016/j.celrep.2022.111548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 08/30/2022] [Accepted: 09/30/2022] [Indexed: 11/20/2022] Open
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16
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Komatsu M, Mannen H, Taniguchi M, Oshima K. Expression and differential posttranscriptional regulation of the elongation factor 1 alpha 1 gene in endometrial caruncle and intercaruncle of Japanese Black cattle at early and mid-gestation stages. Anim Sci J 2022; 93:e13746. [PMID: 35791676 DOI: 10.1111/asj.13746] [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: 01/01/2022] [Revised: 05/24/2022] [Accepted: 05/30/2022] [Indexed: 11/30/2022]
Abstract
The elongation factor 1 alpha 1 (EEF1A1), an isoform of EEF1A, is one of the most abundant cytoplasmic proteins and an important component of the translational machinery. We investigated the relative expression, alternative polyadenylation (APA), and changes in poly(A) tail length of EEF1A1 mRNA in the endometrial caruncle (CAR) and intercaruncle (ICAR) at early and mid-gestation in Japanese Black cattle. The relative EEF1A1 mRNA expression levels in the CAR were the highest on Gestation day 20 and were significantly decreased at mid-gestation. The expression levels in the ICAR were significantly higher than those in the CAR, and the gestation stage had no significant impact. Four different EEF1A1 transcripts with distinct 3' untranslated regions (UTRs) (proximal and distal types) and poly(A) tails (medium and short types) of different lengths were identified. The EEF1A1 mRNAs with distal 3' UTR and medium-length poly(A) tails were specific from the CAR of uterus horn at early gestation. RNA-sequencing data analyses revealed that the HSF1, MZF1, E47, SRF, GATA2, GATA3, GATA6, HNF-3 beta (FOXA2), CPSF1, and Ataxin-2 genes might affect the EEF1A1 gene expression or poly(A) length.
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Affiliation(s)
- Masanori Komatsu
- Komatsu Laboratory of Computational Biology for Domestic Animals, Ryugasaki, Japan.,Division of Tear-Round Grazing Research, Western Region Agricultural Research Center, NARO, Oda, Japan
| | - Hideyuki Mannen
- Graduate School of Agricultural Science, Kobe University, Kobe, Japan
| | - Masaaki Taniguchi
- Division of Animal Breeding and Reproduction Research, Institute of Livestock and Grassland Science, National Agriculture Food Research Organization (NARO), Tsukuba, Japan
| | - Kazunaga Oshima
- Division of Tear-Round Grazing Research, Western Region Agricultural Research Center, NARO, Oda, Japan
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17
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Huelsmeier J, Walker E, Bakthavachalu B, Ramaswami M. A C-terminal ataxin-2 disordered region promotes Huntingtin protein aggregation and neurodegeneration in Drosophila models of Huntington’s disease. G3 GENES|GENOMES|GENETICS 2021; 11:6385240. [PMID: 34718534 PMCID: PMC8664476 DOI: 10.1093/g3journal/jkab355] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 10/01/2021] [Indexed: 11/15/2022]
Abstract
The Ataxin-2 (Atx2) protein contributes to the progression of neurodegenerative phenotypes in animal models of amyotrophic lateral sclerosis (ALS), type 2 spinocerebellar ataxia (SCA-2), Parkinson’s disease, and Huntington’s disease (HD). However, because the Atx2 protein contains multiple separable activities, deeper understanding requires experiments to address the exact mechanisms by which Atx2 modulates neurodegeneration (ND) progression. Recent work on two ALS models, C9ORF72 and FUS, in Drosophila has shown that a C-terminal intrinsically disordered region (cIDR) of Atx2 protein, required for assembly of ribonucleoprotein (RNP) granules, is essential for the progression of neurodegenerative phenotypes as well as for accumulation of protein inclusions associated with these ALS models. Here, we show that the Atx2-cIDR also similarly contributes to the progression of degenerative phenotypes and accumulation of Huntingtin protein aggregates in Drosophila models of HD. Because Huntingtin is not an established component of RNP granules, these observations support a recently hypothesized, unexpected protein-handling function for RNP granules, which could contribute to the progression of Huntington’s disease and, potentially, other proteinopathies.
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Affiliation(s)
- Joern Huelsmeier
- School of Genetics and Microbiology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Emily Walker
- School of Genetics and Microbiology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
| | - Baskar Bakthavachalu
- School of Basic Science, Indian Institute of Technology, Mandi, Suran 175075, India
| | - Mani Ramaswami
- School of Genetics and Microbiology, Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin 2, Ireland
- National Centre for Biological Sciences, TIFR, Bangalore 560065, India
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18
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RNA Modifications and RNA Metabolism in Neurological Disease Pathogenesis. Int J Mol Sci 2021; 22:ijms222111870. [PMID: 34769301 PMCID: PMC8584444 DOI: 10.3390/ijms222111870] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/16/2021] [Accepted: 10/26/2021] [Indexed: 02/06/2023] Open
Abstract
The intrinsic cellular heterogeneity and molecular complexity of the mammalian nervous system relies substantially on the dynamic nature and spatiotemporal patterning of gene expression. These features of gene expression are achieved in part through mechanisms involving various epigenetic processes such as DNA methylation, post-translational histone modifications, and non-coding RNA activity, amongst others. In concert, another regulatory layer by which RNA bases and sugar residues are chemically modified enhances neuronal transcriptome complexity. Similar RNA modifications in other systems collectively constitute the cellular epitranscriptome that integrates and impacts various physiological processes. The epitranscriptome is dynamic and is reshaped constantly to regulate vital processes such as development, differentiation and stress responses. Perturbations of the epitranscriptome can lead to various pathogenic conditions, including cancer, cardiovascular abnormalities and neurological diseases. Recent advances in next-generation sequencing technologies have enabled us to identify and locate modified bases/sugars on different RNA species. These RNA modifications modulate the stability, transport and, most importantly, translation of RNA. In this review, we discuss the formation and functions of some frequently observed RNA modifications—including methylations of adenine and cytosine bases, and isomerization of uridine to pseudouridine—at various layers of RNA metabolism, together with their contributions to abnormal physiological conditions that can lead to various neurodevelopmental and neurological disorders.
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19
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McIntosh CS, Li D, Wilton SD, Aung-Htut MT. Polyglutamine Ataxias: Our Current Molecular Understanding and What the Future Holds for Antisense Therapies. Biomedicines 2021; 9:1499. [PMID: 34829728 PMCID: PMC8615177 DOI: 10.3390/biomedicines9111499] [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: 09/17/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 02/07/2023] Open
Abstract
Polyglutamine (polyQ) ataxias are a heterogenous group of neurological disorders all caused by an expanded CAG trinucleotide repeat located in the coding region of each unique causative gene. To date, polyQ ataxias encompass six disorders: spinocerebellar ataxia types 1, 2, 3, 6, 7, and 17 and account for a larger group of disorders simply known as polyglutamine disorders, which also includes Huntington's disease. These diseases are typically characterised by progressive ataxia, speech and swallowing difficulties, lack of coordination and gait, and are unfortunately fatal in nature, with the exception of SCA6. All the polyQ spinocerebellar ataxias have a hallmark feature of neuronal aggregations and share many common pathogenic mechanisms, such as mitochondrial dysfunction, impaired proteasomal function, and autophagy impairment. Currently, therapeutic options are limited, with no available treatments that slow or halt disease progression. Here, we discuss the common molecular and clinical presentations of polyQ spinocerebellar ataxias. We will also discuss the promising antisense oligonucleotide therapeutics being developed as treatments for these devastating diseases. With recent advancements and therapeutic approvals of various antisense therapies, it is envisioned that some of the studies reviewed may progress into clinical trials and beyond.
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Affiliation(s)
- Craig S. McIntosh
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Dunhui Li
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
| | - Steve D. Wilton
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
| | - May T. Aung-Htut
- Molecular Therapy Laboratory, Centre for Molecular Medicine and Innovative Therapeutics, Health Futures Institute Murdoch University, Discovery Way, Murdoch, WA 6150, Australia; (C.S.M.); (D.L.); (S.D.W.)
- Perron Institute for Neurological and Translational Science, Centre for Neuromuscular and Neurological Disorders, The University of Western Australia, Nedlands, WA 6009, Australia
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20
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Abstract
PURPOSE OF REVIEW To provide an update on the role of Ataxin-2 gene (ATXN2) in health and neurological diseases. RECENT FINDINGS There is a growing complexity emerging on the role of ATXN2 and its variants in association with SCA2 and several other neurological diseases. Polymorphisms and intermediate alleles in ATXN2 establish this gene as a powerful modulator of neurological diseases including lethal neurodegenerative conditions such as motor neuron disease, spinocerebellar ataxia 3 (SCA3), and peripheral nerve disease such as familial amyloidosis polyneuropathy. This role is in fact far wider than the previously described for polymorphism in the prion protein (PRNP) gene. Positive data from antisense oligo therapy in a murine model of SCA2 suggest that similar approaches may be feasible in humans SCA2 patients. SUMMARY ATXN2 is one of the few genes where a single gene causes several diseases and/or modifies several and disparate neurological disorders. Hence, understanding mutagenesis, genetic variants, and biological functions will help managing SCA2, and several human diseases connected with dysfunctional pathways in the brain, innate immunity, autophagy, cellular, lipid, and RNA metabolism.
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Affiliation(s)
- Jose Miguel Laffita-Mesa
- Department of Clinical Neuroscience (CNS), J5:20 Bioclinicum, Karolinska University Hospital, Stockholm, Sweden
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21
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Inagaki H, Hosoda N, Hoshino SI. DDX6 is a positive regulator of Ataxin-2/PAPD4 cytoplasmic polyadenylation machinery. Biochem Biophys Res Commun 2021; 553:9-16. [PMID: 33756349 DOI: 10.1016/j.bbrc.2021.03.066] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 03/12/2021] [Indexed: 12/20/2022]
Abstract
The RNA-binding protein Ataxin-2 regulates translation and mRNA stability through cytoplasmic polyadenylation of the targets. Here we newly identified DDX6 as a positive regulator of the cytoplasmic polyadenylation. Analysis of Ataxin-2 interactome using LC-MS/MS revealed prominent interaction with the DEAD-box RNA helicase DDX6. DDX6 interacted with components of the Ataxin-2 polyadenylation machinery; Ataxin-2, PABPC1 and PAPD4. As in the case for Ataxin-2 downregulation, DDX6 downregulation led to an increase in Ataxin-2 target mRNAs with short poly(A) tails as well as a reduction in their protein expression. In contrast, Ataxin-2 target mRNAs with short poly(A) tails were decreased by the overexpression of Ataxin-2, which was compromised by the DDX6 downregulation. However, polyadenylation induced by Ataxin-2 tethering was not affected by the DDX6 downregulation. Taken together, these results suggest that DDX6 positively regulates Ataxin-2-induced cytoplasmic polyadenylation to maintain poly(A) tail length of the Ataxin-2 targets provably through accelerating binding of Ataxin-2 to the target mRNAs.
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Affiliation(s)
- Hiroto Inagaki
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, 467-8603, Japan
| | - Nao Hosoda
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, 467-8603, Japan
| | - Shin-Ichi Hoshino
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya, 467-8603, Japan.
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The ATXN2 Orthologs CID3 and CID4, Act Redundantly to In-Fluence Developmental Pathways throughout the Life Cycle of Arabidopsis thaliana. Int J Mol Sci 2021; 22:ijms22063068. [PMID: 33802796 PMCID: PMC8002431 DOI: 10.3390/ijms22063068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 02/15/2021] [Accepted: 02/15/2021] [Indexed: 11/17/2022] Open
Abstract
RNA-binding proteins (RBPs) are key elements involved in post-transcriptional regulation. Ataxin-2 (ATXN2) is an evolutionarily conserved RBP protein, whose function has been studied in several model organisms, from Saccharomyces cerevisiae to the Homo sapiens. ATXN2 interacts with poly(A) binding proteins (PABP) and binds to specific sequences at the 3'UTR of target mRNAs to stabilize them. CTC-Interacting Domain3 (CID3) and CID4 are two ATXN2 orthologs present in plant genomes whose function is unknown. In the present study, phenotypical and transcriptome profiling were used to examine the role of CID3 and CID4 in Arabidopsis thaliana. We found that they act redundantly to influence pathways throughout the life cycle. cid3cid4 double mutant showed a delay in flowering time and a reduced rosette size. Transcriptome profiling revealed that key factors that promote floral transition and floral meristem identity were downregulated in cid3cid4 whereas the flowering repressor FLOWERING LOCUS C (FLC) was upregulated. Expression of key factors in the photoperiodic regulation of flowering and circadian clock pathways, were also altered in cid3cid4, as well as the expression of several transcription factors and miRNAs encoding genes involved in leaf growth dynamics. These findings reveal that ATXN2 orthologs may have a role in developmental pathways throughout the life cycle of plants.
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23
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Singh A, Hulsmeier J, Kandi AR, Pothapragada SS, Hillebrand J, Petrauskas A, Agrawal K, RT K, Thiagarajan D, Jayaprakashappa D, VijayRaghavan K, Ramaswami M, Bakthavachalu B. Antagonistic roles for Ataxin-2 structured and disordered domains in RNP condensation. eLife 2021; 10:e60326. [PMID: 33689682 PMCID: PMC7946432 DOI: 10.7554/elife.60326] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 02/23/2021] [Indexed: 02/07/2023] Open
Abstract
Ataxin-2 (Atx2) is a translational control molecule mutated in spinocerebellar ataxia type II and amyotrophic lateral sclerosis. While intrinsically disordered domains (IDRs) of Atx2 facilitate mRNP condensation into granules, how IDRs work with structured domains to enable positive and negative regulation of target mRNAs remains unclear. Using the Targets of RNA-Binding Proteins Identified by Editing technology, we identified an extensive data set of Atx2-target mRNAs in the Drosophila brain and S2 cells. Atx2 interactions with AU-rich elements in 3'UTRs appear to modulate stability/turnover of a large fraction of these target mRNAs. Further genomic and cell biological analyses of Atx2 domain deletions demonstrate that Atx2 (1) interacts closely with target mRNAs within mRNP granules, (2) contains distinct protein domains that drive or oppose RNP-granule assembly, and (3) has additional essential roles outside of mRNP granules. These findings increase the understanding of neuronal translational control mechanisms and inform strategies for Atx2-based interventions under development for neurodegenerative disease.
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Affiliation(s)
- Amanjot Singh
- National Centre for Biological SciencesBangaloreIndia
| | - Joern Hulsmeier
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Arvind Reddy Kandi
- National Centre for Biological SciencesBangaloreIndia
- Tata Institute for Genetics and Society Centre at inStem, Bellary RoadBangaloreIndia
| | | | - Jens Hillebrand
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Arnas Petrauskas
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Khushboo Agrawal
- Tata Institute for Genetics and Society Centre at inStem, Bellary RoadBangaloreIndia
- School of Biotechnology, Amrita Vishwa Vidyapeetham UniversityKollamIndia
| | - Krishnan RT
- National Centre for Biological SciencesBangaloreIndia
| | | | | | | | - Mani Ramaswami
- National Centre for Biological SciencesBangaloreIndia
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology, Smurfit Institute of Genetics and School of Natural Sciences, Trinity College DublinDublinIreland
| | - Baskar Bakthavachalu
- National Centre for Biological SciencesBangaloreIndia
- Tata Institute for Genetics and Society Centre at inStem, Bellary RoadBangaloreIndia
- School of Basic Sciences, Indian Institute of TechnologyMandiIndia
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