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Neumann DP, Phillips CA, Lumb R, Palethorpe HM, Ramani Y, Hollier BG, Selth LA, Bracken CP, Goodall GJ, Gregory PA. Quaking isoforms cooperate to promote the mesenchymal phenotype. Mol Biol Cell 2024; 35:ar17. [PMID: 38019605 PMCID: PMC10881146 DOI: 10.1091/mbc.e23-08-0316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 10/18/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023] Open
Abstract
The RNA-binding protein Quaking (QKI) has widespread effects on mRNA regulation including alternative splicing, stability, translation, and localization of target mRNAs. Recently, QKI was found to be induced during epithelial-mesenchymal transition (EMT), where it promotes a mesenchymal alternative splicing signature that contributes to the mesenchymal phenotype. QKI is itself alternatively spliced to produce three major isoforms, QKI-5, QKI-6, and QKI-7. While QKI-5 is primarily localized to the nucleus where it controls mesenchymal splicing during EMT, the functions of the two predominantly cytoplasmic isoforms, QKI-6 and QKI-7, in this context remain uncharacterized. Here we used CRISPR-mediated depletion of QKI in a human mammary epithelial cell model of EMT and studied the effects of expressing the QKI isoforms in isolation and in combination. QKI-5 was required to induce mesenchymal morphology, while combined expression of QKI-5 with either QKI-6 or QKI-7 further enhanced mesenchymal morphology and cell migration. In addition, we found that QKI-6 and QKI-7 can partially localize to the nucleus and contribute to alternative splicing of QKI target genes. These findings indicate that the QKI isoforms function in a dynamic and cooperative manner to promote the mesenchymal phenotype.
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Affiliation(s)
- Daniel P. Neumann
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Caroline A. Phillips
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Rachael Lumb
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Helen M. Palethorpe
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Yesha Ramani
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
| | - Brett G. Hollier
- Australian Prostate Cancer Research Centre - Queensland, Centre for Genomics and Personalised Health, Faculty of Health, School of Biomedical Sciences, Queensland University of Technology, Translational Research Institute, Brisbane, Queensland 4102, Australia
| | - Luke A. Selth
- Flinders Health and Medical Research Institute and Freemasons Centre for Male Health and Wellbeing, Flinders University, Bedford Park, South Australia 5042, Australia
- Faculty of Health and Medical Sciences, and
| | - Cameron P. Bracken
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
- Faculty of Health and Medical Sciences, and
- School of Biological Sciences, Faculty of Sciences, Engineering and Technology, The University of Adelaide, Adelaide, South Australia 5000, Australia
| | - Gregory J. Goodall
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
- Faculty of Health and Medical Sciences, and
- School of Biological Sciences, Faculty of Sciences, Engineering and Technology, The University of Adelaide, Adelaide, South Australia 5000, Australia
| | - Philip A. Gregory
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, South Australia 5000, Australia
- Faculty of Health and Medical Sciences, and
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2
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Neumann DP, Pillman KA, Dredge BK, Bert AG, Phillips CA, Lumb R, Ramani Y, Bracken CP, Hollier BG, Selth LA, Beilharz TH, Goodall GJ, Gregory PA. The landscape of alternative polyadenylation during EMT and its regulation by the RNA-binding protein Quaking. RNA Biol 2024; 21:1-11. [PMID: 38112323 PMCID: PMC10732628 DOI: 10.1080/15476286.2023.2294222] [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] [Accepted: 12/05/2023] [Indexed: 12/21/2023] Open
Abstract
Epithelial-mesenchymal transition (EMT) plays important roles in tumour progression and is orchestrated by dynamic changes in gene expression. While it is well established that post-transcriptional regulation plays a significant role in EMT, the extent of alternative polyadenylation (APA) during EMT has not yet been explored. Using 3' end anchored RNA sequencing, we mapped the alternative polyadenylation (APA) landscape following Transforming Growth Factor (TGF)-β-mediated induction of EMT in human mammary epithelial cells and found APA generally causes 3'UTR lengthening during this cell state transition. Investigation of potential mediators of APA indicated the RNA-binding protein Quaking (QKI), a splicing factor induced during EMT, regulates a subset of events including the length of its own transcript. Analysis of QKI crosslinked immunoprecipitation (CLIP)-sequencing data identified the binding of QKI within 3' untranslated regions (UTRs) was enriched near cleavage and polyadenylation sites. Following QKI knockdown, APA of many transcripts is altered to produce predominantly shorter 3'UTRs associated with reduced gene expression. These findings reveal the changes in APA that occur during EMT and identify a potential role for QKI in this process.
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Affiliation(s)
- Daniel P. Neumann
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - Katherine A. Pillman
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - B. Kate Dredge
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - Andrew G. Bert
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - Caroline A. Phillips
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - Rachael Lumb
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - Yesha Ramani
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
| | - Cameron P. Bracken
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Brett G. Hollier
- Australian Prostate Cancer Research Centre - Queensland, Centre for Genomics and Personalised Health, Faculty of Health, School of Biomedical Sciences, Queensland University of Technology, Brisbane, QLD, Australia
| | - Luke A. Selth
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
- Flinders Health and Medical Research Institute, Flinders University, Bedford Park, SA, Australia
| | - Traude H. Beilharz
- Development and Stem Cells Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Melbourne, Australia
| | - Gregory J. Goodall
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
| | - Philip A. Gregory
- Centre for Cancer Biology, University of South Australia and SA Pathology, Adelaide, SA, Australia
- Faculty of Health and Medical Sciences, The University of Adelaide, Adelaide, SA, Australia
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3
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Min KW, Jo MH, Song M, Lee JW, Shim MJ, Kim K, Park HB, Ha S, Mun H, Polash A, Hafner M, Cho JH, Kim D, Jeong JH, Ko S, Hohng S, Kang SU, Yoon JH. Mature microRNA-binding protein QKI promotes microRNA-mediated gene silencing. RNA Biol 2024; 21:1-15. [PMID: 38372062 PMCID: PMC10878027 DOI: 10.1080/15476286.2024.2314846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/29/2024] [Indexed: 02/20/2024] Open
Abstract
Although Argonaute (AGO) proteins have been the focus of microRNA (miRNA) studies, we observed AGO-free mature miRNAs directly interacting with RNA-binding proteins, implying the sophisticated nature of fine-tuning gene regulation by miRNAs. To investigate microRNA-binding proteins (miRBPs) globally, we analyzed PAR-CLIP data sets to identify RBP quaking (QKI) as a novel miRBP for let-7b. Potential existence of AGO-free miRNAs were further verified by measuring miRNA levels in genetically engineered AGO-depleted human and mouse cells. We have shown that QKI regulates miRNA-mediated gene silencing at multiple steps, and collectively serves as an auxiliary factor empowering AGO2/let-7b-mediated gene silencing. Depletion of QKI decreases interaction of AGO2 with let-7b and target mRNA, consequently controlling target mRNA decay. This finding indicates that QKI is a complementary factor in miRNA-mediated mRNA decay. QKI, however, also suppresses the dissociation of let-7b from AGO2, and slows the assembly of AGO2/miRNA/target mRNA complexes at the single-molecule level. We also revealed that QKI overexpression suppresses cMYC expression at post-transcriptional level, and decreases proliferation and migration of HeLa cells, demonstrating that QKI is a tumour suppressor gene by in part augmenting let-7b activity. Our data show that QKI is a new type of RBP implicated in the versatile regulation of miRNA-mediated gene silencing.
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Affiliation(s)
- Kyung-Won Min
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
- Department of Biology, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Myung Hyun Jo
- Department of Physics & Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Minseok Song
- Department of Physics & Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Ji Won Lee
- Department of Biology, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Min Ji Shim
- Department of Biology, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Kyungmin Kim
- Department of Biology, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Hyun Bong Park
- Department of Biology, Gangneung-Wonju National University, Gangneung, Republic of Korea
| | - Shinwon Ha
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Hyejin Mun
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
- Department of Oncology Science, University of Oklahoma, Oklahoma City, USA
| | - Ahsan Polash
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, USA
| | - Markus Hafner
- Laboratory of Muscle Stem Cells and Gene Regulation, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, USA
| | - Jung-Hyun Cho
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Dongsan Kim
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Ji-Hoon Jeong
- Department of Oncology Science, University of Oklahoma, Oklahoma City, USA
- Department of Biochemistry and Molecular Biology, University of Ulsan College of Medicine, Seoul, Korea
| | - Seungbeom Ko
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Sungchul Hohng
- Department of Physics & Astronomy, Seoul National University, Seoul, Republic of Korea
| | - Sung-Ung Kang
- Neuroregeneration and Stem Cell Programs, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, USA
| | - Je-Hyun Yoon
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, USA
- Department of Oncology Science, University of Oklahoma, Oklahoma City, USA
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4
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Maltseva D, Tonevitsky A. RNA-binding proteins regulating the CD44 alternative splicing. Front Mol Biosci 2023; 10:1326148. [PMID: 38106992 PMCID: PMC10722200 DOI: 10.3389/fmolb.2023.1326148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 11/15/2023] [Indexed: 12/19/2023] Open
Abstract
Alternative splicing is often deregulated in cancer, and cancer-specific isoform switches are part of the oncogenic transformation of cells. Accumulating evidence indicates that isoforms of the multifunctional cell-surface glycoprotein CD44 play different roles in cancer cells as compared to normal cells. In particular, the shift of CD44 isoforms is required for epithelial to mesenchymal transition (EMT) and is crucial for the maintenance of pluripotency in normal human cells and the acquisition of cancer stem cells phenotype for malignant cells. The growing and seemingly promising use of splicing inhibitors for treating cancer and other pathologies gives hope for the prospect of using such an approach to regulate CD44 alternative splicing. This review integrates current knowledge about regulating CD44 alternative splicing by RNA-binding proteins.
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Affiliation(s)
- Diana Maltseva
- Faculty of Biology and Biotechnology, HSE University, Moscow, Russia
| | - Alexander Tonevitsky
- Faculty of Biology and Biotechnology, HSE University, Moscow, Russia
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
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5
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Israel-Elgali I, Pan H, Oved K, Pillar N, Levy G, Barak B, Carneiro A, Gurwitz D, Shomron N. Impaired myelin ultrastructure is reversed by citalopram treatment in a mouse model for major depressive disorder. J Psychiatr Res 2023; 166:100-114. [PMID: 37757703 DOI: 10.1016/j.jpsychires.2023.09.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 07/24/2023] [Accepted: 09/15/2023] [Indexed: 09/29/2023]
Abstract
Major depressive disorder (MDD) is the most common and widespread mental disorder. Selective serotonin reuptake inhibitors (SSRIs) are the first-line treatment for MDD. The relation between the inhibition of serotonin reuptake in the central nervous system and remission from MDD remains controversial, as reuptake inhibition occurs rapidly, but remission from MDD takes weeks to months. Myelination-related deficits and white matter abnormalities were shown to be involved in psychiatric disorders such as MDD. This may explain the delay in remission following SSRI administration. The raphe nuclei (RN), located in the brain stem, consist of clusters of serotonergic (5-HT) neurons that project to almost all regions of the brain. Thus, the RN are an intriguing area for research of the potential effect of SSRI on myelination, and their involvement in MDD. MicroRNAs (miRNAs) regulate many biological features that might be altered by antidepressants. Two cohorts of chronic unpredictable stress (CUS) mouse model for depression underwent behavioral tests for evaluating stress, anxiety, and depression levels. Following application of the CUS protocol and treatment with the SSRI, citalopram, 48 mice of the second cohort were tested via magnetic resonance imaging and diffusion tensor imaging for differences in brain white matter tracts. RN and superior colliculus were excised from both cohorts and measured for changes in miRNAs, mRNA, and protein levels of candidate genes. Using MRI-DTI scans we found lower fractional anisotropy and axial diffusivity in brains of stressed mice. Moreover, both miR-30b-5p and miR-101a-3p were found to be downregulated in the RN following CUS, and upregulated following CUS and citalopram treatment. The direct binding of these miRNAs to Qki, and the subsequent effects on mRNA and protein levels of myelin basic protein (Mbp), indicated involvement of these miRNAs in myelination ultrastructure processes in the RN, in response to CUS followed by SSRI treatment. We suggest that SSRIs are implicated in repairing myelin deficits resulting from chronic stress that leads to depression.
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Affiliation(s)
- Ifat Israel-Elgali
- Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel; Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Hope Pan
- Department of Pharmacology, Center for Molecular Neuroscience, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Keren Oved
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Nir Pillar
- Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Gilad Levy
- Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel
| | - Boaz Barak
- Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel; Faculty of Social Sciences, School of Psychological Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Ana Carneiro
- Department of Pharmacology, Center for Molecular Neuroscience, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - David Gurwitz
- Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel; Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | - Noam Shomron
- Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv, Israel; Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Edmond J Safra Center for Bioinformatics, Tel Aviv University, Tel Aviv, Israel; Tel Aviv University Innovation Laboratories (TILabs), Tel Aviv, Israel.
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6
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Krawczyk MC, Pan L, Zhang AJ, Zhang Y. Lymphocyte deficiency alters the transcriptomes of oligodendrocytes, but not astrocytes or microglia. PLoS One 2023; 18:e0279736. [PMID: 36827449 PMCID: PMC9956607 DOI: 10.1371/journal.pone.0279736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 12/14/2022] [Indexed: 02/26/2023] Open
Abstract
Though the brain was long characterized as an immune-privileged organ, findings in recent years have shown extensive communications between the brain and peripheral immune cells. We now know that alterations in the peripheral immune system can affect the behavioral outputs of the central nervous system, but we do not know which brain cells are affected by the presence of peripheral immune cells. Glial cells including microglia, astrocytes, oligodendrocytes, and oligodendrocyte precursor cells (OPCs) are critical for the development and function of the central nervous system. In a wide range of neurological and psychiatric diseases, the glial cell state is influenced by infiltrating peripheral lymphocytes. However, it remains largely unclear whether the development of the molecular phenotypes of glial cells in the healthy brain is regulated by lymphocytes. To answer this question, we acutely purified each type of glial cell from immunodeficient Rag2-/- mice. Interestingly, we found that the transcriptomes of microglia, astrocytes, and OPCs developed normally in Rag2-/- mice without reliance on lymphocytes. In contrast, there are modest transcriptome differences between the oligodendrocytes from Rag2-/- and control mice. Furthermore, the subcellular localization of the RNA-binding protein Quaking, is altered in oligodendrocytes. These results demonstrate that the molecular attributes of glial cells develop largely without influence from lymphocytes and highlight potential interactions between lymphocytes and oligodendrocytes.
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Affiliation(s)
- Mitchell C. Krawczyk
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
| | - Lin Pan
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
| | - Alice J. Zhang
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
| | - Ye Zhang
- Department of Psychiatry and Biobehavioral Sciences, Intellectual and Developmental Disabilities Research Center, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
- Brain Research Institute, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
- Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
- Molecular Biology Institute, University of California Los Angeles (UCLA), Los Angeles, Los Angeles, California, United States of America
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7
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Gala DS, Titlow JS, Teodoro RO, Davis I. Far from home: the role of glial mRNA localization in synaptic plasticity. RNA (NEW YORK, N.Y.) 2023; 29:153-169. [PMID: 36442969 PMCID: PMC9891262 DOI: 10.1261/rna.079422.122] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Neurons and glia are highly polarized cells, whose distal cytoplasmic functional subdomains require specific proteins. Neurons have axonal and dendritic cytoplasmic extensions containing synapses whose plasticity is regulated efficiently by mRNA transport and localized translation. The principles behind these mechanisms are equally attractive for explaining rapid local regulation of distal glial cytoplasmic projections, independent of their cell nucleus. However, in contrast to neurons, mRNA localization has received little experimental attention in glia. Nevertheless, there are many functionally diverse glial subtypes containing extensive networks of long cytoplasmic projections with likely localized regulation that influence neurons and their synapses. Moreover, glia have many other neuron-like properties, including electrical activity, secretion of gliotransmitters and calcium signaling, influencing, for example, synaptic transmission, plasticity and axon pruning. Here, we review previous studies concerning glial transcripts with important roles in influencing synaptic plasticity, focusing on a few cases involving localized translation. We discuss a variety of important questions about mRNA transport and localized translation in glia that remain to be addressed, using cutting-edge tools already available for neurons.
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Affiliation(s)
- Dalia S Gala
- Department of Biochemistry, The University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Joshua S Titlow
- Department of Biochemistry, The University of Oxford, Oxford OX1 3QU, United Kingdom
| | - Rita O Teodoro
- iNOVA4Health, NOVA Medical School-Faculdade de Ciências Médicas, Universidade Nova de Lisboa, Lisboa 1169-056, Portugal
| | - Ilan Davis
- Department of Biochemistry, The University of Oxford, Oxford OX1 3QU, United Kingdom
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Barnes-Vélez JA, Aksoy Yasar FB, Hu J. Myelin lipid metabolism and its role in myelination and myelin maintenance. Innovation (N Y) 2023; 4:100360. [PMID: 36588745 PMCID: PMC9800635 DOI: 10.1016/j.xinn.2022.100360] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Myelin is a specialized cell membrane indispensable for rapid nerve conduction. The high abundance of membrane lipids is one of myelin's salient features that contribute to its unique role as an insulator that electrically isolates nerve fibers across their myelinated surface. The most abundant lipids in myelin include cholesterol, glycosphingolipids, and plasmalogens, each playing critical roles in myelin development as well as function. This review serves to summarize the role of lipid metabolism in myelination and myelin maintenance, as well as the molecular determinants of myelin lipid homeostasis, with an emphasis on findings from genetic models. In addition, the implications of myelin lipid dysmetabolism in human diseases are highlighted in the context of hereditary leukodystrophies and neuropathies as well as acquired disorders such as Alzheimer's disease.
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Affiliation(s)
- Joseph A. Barnes-Vélez
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054-1901, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, TX 77225-0334, USA
- University of Puerto Rico Medical Sciences Campus, School of Medicine, San Juan, PR 00936-5067, USA
| | - Fatma Betul Aksoy Yasar
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054-1901, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, TX 77225-0334, USA
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX 77054-1901, USA
- MD Anderson Cancer Center UTHealth Graduate School of Biomedical Science, Houston, TX 77225-0334, USA
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9
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Lefaudeux D, Sen S, Jiang K, Hoffmann A. Kinetics of mRNA nuclear export regulate innate immune response gene expression. Nat Commun 2022; 13:7197. [PMID: 36424375 PMCID: PMC9691726 DOI: 10.1038/s41467-022-34635-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Accepted: 11/01/2022] [Indexed: 11/25/2022] Open
Abstract
The abundance and stimulus-responsiveness of mature mRNA is thought to be determined by nuclear synthesis, processing, and cytoplasmic decay. However, the rate and efficiency of moving mRNA to the cytoplasm almost certainly contributes, but has rarely been measured. Here, we investigated mRNA export rates for innate immune genes. We generated high spatio-temporal resolution RNA-seq data from endotoxin-stimulated macrophages and parameterized a mathematical model to infer kinetic parameters with confidence intervals. We find that the effective chromatin-to-cytoplasm export rate is gene-specific, varying 100-fold: for some genes, less than 5% of synthesized transcripts arrive in the cytoplasm as mature mRNAs, while others show high export efficiency. Interestingly, effective export rates do not determine temporal gene responsiveness, but complement the wide range of mRNA decay rates; this ensures similar abundances of short- and long-lived mRNAs, which form successive innate immune response expression waves.
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Affiliation(s)
- Diane Lefaudeux
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, CA, 90095, USA
| | - Supriya Sen
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Kevin Jiang
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA
- Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, CA, 90095, USA
| | - Alexander Hoffmann
- Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, CA, 90095, USA.
- Institute for Quantitative and Computational Biosciences, University of California, Los Angeles, CA, 90095, USA.
- Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA.
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10
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Chen Y, Qin H, Zheng L. Research progress on RNA−binding proteins in breast cancer. Front Oncol 2022; 12:974523. [PMID: 36059653 PMCID: PMC9433872 DOI: 10.3389/fonc.2022.974523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Accepted: 07/27/2022] [Indexed: 11/16/2022] Open
Abstract
Breast cancer is the most common malignancy in women and has a high incidence rate and mortality. Abnormal regulation of gene expression plays an important role in breast cancer occurrence and development. RNA-binding proteins (RBPs) are one kind of the key regulators for gene expression. By interacting with RNA, RBPs are widely involved in RNA cutting, transport, editing, intracellular localization, and translation regulation. RBPs are important during breast cancer occurrence and progression by engaging in many aspects, like proliferation, migration, invasion, and stemness. Therefore, comprehensively understanding the role of RBPs in breast cancer progression can facilitate early diagnosis, timely treatment, and long-term survival and quality of life of breast cancer patients.
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Affiliation(s)
- Ying Chen
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, Nanjing, China
| | - Hai Qin
- Department of Clinical Laboratory, Guizhou Provincial Orthopedic Hospital, Guiyang, China
- *Correspondence: Lufeng Zheng, ; Hai Qin,
| | - Lufeng Zheng
- School of Life Science and Technology, Jiangsu Key Laboratory of Carcinogenesis and Intervention, China Pharmaceutical University, Nanjing, China
- *Correspondence: Lufeng Zheng, ; Hai Qin,
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11
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Fagg WS, Liu N, Braunschweig U, Pereira de Castro K, Chen X, Ditmars F, Widen S, Donohue JP, Modis K, Russell W, Fair JH, Weirauch M, Blencowe B, Garcia-Blanco M. Definition of germ layer cell lineage alternative splicing programs reveals a critical role for Quaking in specifying cardiac cell fate. Nucleic Acids Res 2022; 50:5313-5334. [PMID: 35544276 PMCID: PMC9122611 DOI: 10.1093/nar/gkac327] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/14/2022] [Accepted: 04/25/2022] [Indexed: 01/27/2023] Open
Abstract
Alternative splicing is critical for development; however, its role in the specification of the three embryonic germ layers is poorly understood. By performing RNA-Seq on human embryonic stem cells (hESCs) and derived definitive endoderm, cardiac mesoderm, and ectoderm cell lineages, we detect distinct alternative splicing programs associated with each lineage. The most prominent splicing program differences are observed between definitive endoderm and cardiac mesoderm. Integrative multi-omics analyses link each program with lineage-enriched RNA binding protein regulators, and further suggest a widespread role for Quaking (QKI) in the specification of cardiac mesoderm. Remarkably, knockout of QKI disrupts the cardiac mesoderm-associated alternative splicing program and formation of myocytes. These changes arise in part through reduced expression of BIN1 splice variants linked to cardiac development. Mechanistically, we find that QKI represses inclusion of exon 7 in BIN1 pre-mRNA via an exonic ACUAA motif, and this is concomitant with intron removal and cleavage from chromatin. Collectively, our results uncover alternative splicing programs associated with the three germ lineages and demonstrate an important role for QKI in the formation of cardiac mesoderm.
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Affiliation(s)
- W Samuel Fagg
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Naiyou Liu
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
| | | | | | - Xiaoting Chen
- Center for Autoimmune Genomics and Etiology (CAGE), Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Frederick S Ditmars
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Steven G Widen
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - John Paul Donohue
- Sinsheimer Labs, RNA Center for Molecular Biology, Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064, USA
| | - Katalin Modis
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - William K Russell
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Jeffrey H Fair
- Department of Surgery, University of Texas Medical Branch, Galveston, TX 77555, USA
| | - Matthew T Weirauch
- Center for Autoimmune Genomics and Etiology (CAGE), Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
- Divisions of Biomedical Informatics and Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Benjamin J Blencowe
- Donnelly Centre, University of Toronto, Toronto, ONM5S 3E1, Canada
- Department of Molecular Genetics, University of Toronto, ONM5S 1A8, Canada
| | - Mariano A Garcia-Blanco
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555, USA
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX 77555, USA
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12
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Neumann DP, Goodall GJ, Gregory PA. The Quaking RNA-binding proteins as regulators of cell differentiation. WILEY INTERDISCIPLINARY REVIEWS. RNA 2022; 13:e1724. [PMID: 35298877 PMCID: PMC9786888 DOI: 10.1002/wrna.1724] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/18/2022] [Accepted: 02/21/2022] [Indexed: 12/30/2022]
Abstract
The RNA-binding protein Quaking (QKI) has emerged as a potent regulator of cellular differentiation in developmental and pathological processes. The QKI gene is itself alternatively spliced to produce three major isoforms, QKI-5, QKI-6, and QKI-7, that possess very distinct functions. Here, we highlight roles of the different QKI isoforms in neuronal, vascular, muscle, and monocyte cell differentiation, and during epithelial-mesenchymal transition in cancer progression. QKI isoforms control cell differentiation through regulating alternative splicing, mRNA stability and translation, with activities in gene transcription now also becoming evident. These diverse functions of the QKI isoforms contribute to their broad influences on RNA metabolism and cellular differentiation. This article is categorized under: RNA Interactions with Proteins and Other Molecules > Protein-RNA Interactions: Functional Implications RNA Processing > Splicing Regulation/Alternative Splicing RNA in Disease and Development > RNA in Development.
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Affiliation(s)
- Daniel P. Neumann
- Centre for Cancer BiologyUniversity of South Australia and SA PathologyAdelaideSouth Australia
| | - Gregory J. Goodall
- Centre for Cancer BiologyUniversity of South Australia and SA PathologyAdelaideSouth Australia,Faculty of Health and Medical SciencesThe University of AdelaideAdelaideSouth Australia
| | - Philip A. Gregory
- Centre for Cancer BiologyUniversity of South Australia and SA PathologyAdelaideSouth Australia,Faculty of Health and Medical SciencesThe University of AdelaideAdelaideSouth Australia
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13
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Ren J, Dai C, Zhou X, Barnes JA, Chen X, Wang Y, Yuan L, Shingu T, Heimberger AB, Chen Y, Hu J. Qki is an essential regulator of microglial phagocytosis in demyelination. J Exp Med 2021; 218:191206. [PMID: 33045062 PMCID: PMC7543092 DOI: 10.1084/jem.20190348] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 08/07/2019] [Accepted: 09/03/2020] [Indexed: 12/13/2022] Open
Abstract
The mechanism underpinning the regulation of microglial phagocytosis in demyelinating diseases is unclear. Here, we showed that the Quaking protein (Qki) in microglia was greatly induced by demyelination in the brains of both mice and humans. Deletion of the Quaking gene (Qk) in microglia severely impaired the clearance of myelin debris. Transcriptomic profiling indicated that depletion of Qki impaired total RNA levels and splicing of the genes involved in phagosome formation and maturation. RNA immunoprecipitation (RIP) confirmed the physical interactions between the Qki protein and the mRNAs of Qki targets that are involved in phagocytosis, indicating that Qki regulates their RNA stability. Both Qki depletion and inhibition of Qki target Cd36 greatly reduced the phagocytic activity of microglia and macrophages. The defective uptake and degradation of myelin debris caused by Qki depletion in microglia resulted in unresolved myelin debris that impaired axon integrity, oligodendrocyte maturation, and subsequent remyelination. Thus, our results demonstrate that Qki is an essential regulator of microglia’s phagocytic activity under demyelinating conditions.
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Affiliation(s)
- Jiangong Ren
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Congxin Dai
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX.,Department of Neurosurgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Xin Zhou
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX.,Cancer Research Institute of Jilin University, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Joseph A Barnes
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX.,The University of Texas MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, TX
| | - Xi Chen
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Yunfei Wang
- Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Liang Yuan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX.,Graduate School of Biomedical Sciences, Tufts University, Boston, MA
| | - Takashi Shingu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Amy B Heimberger
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Yiwen Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX.,The University of Texas MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, TX
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14
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Shin S, Zhou H, He C, Wei Y, Wang Y, Shingu T, Zeng A, Wang S, Zhou X, Li H, Zhang Q, Mo Q, Long J, Lan F, Chen Y, Hu J. Qki activates Srebp2-mediated cholesterol biosynthesis for maintenance of eye lens transparency. Nat Commun 2021; 12:3005. [PMID: 34021134 PMCID: PMC8139980 DOI: 10.1038/s41467-021-22782-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 03/23/2021] [Indexed: 02/04/2023] Open
Abstract
Defective cholesterol biosynthesis in eye lens cells is often associated with cataracts; however, how genes involved in cholesterol biosynthesis are regulated in lens cells remains unclear. Here, we show that Quaking (Qki) is required for the transcriptional activation of genes involved in cholesterol biosynthesis in the eye lens. At the transcriptome level, lens-specific Qki-deficient mice present downregulation of genes associated with the cholesterol biosynthesis pathway, resulting in a significant reduction of total cholesterol level in the eye lens. Mice with Qki depletion in lens epithelium display progressive accumulation of protein aggregates, eventually leading to cataracts. Notably, these defects are attenuated by topical sterol administration. Mechanistically, we demonstrate that Qki enhances cholesterol biosynthesis by recruiting Srebp2 and Pol II in the promoter regions of cholesterol biosynthesis genes. Supporting its function as a transcription co-activator, we show that Qki directly interacts with single-stranded DNA. In conclusion, we propose that Qki-Srebp2-mediated cholesterol biosynthesis is essential for maintaining the cholesterol level that protects lens from cataract development.
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Affiliation(s)
- Seula Shin
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
- Cancer Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA
| | - Hao Zhou
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, Tianjin, China
| | - Chenxi He
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yanjun Wei
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Yunfei Wang
- Clinical Science Division, H. Lee Moffitt Cancer Center & Research Institute, Tampa, FL, USA
| | - Takashi Shingu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Ailiang Zeng
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Shaobo Wang
- Department of Neurosurgery, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, China
| | - Xin Zhou
- Cancer Research Institute of Jilin University, The First Hospital of Jilin University, Jilin, China
| | - Hongtao Li
- Department of Oncology, Affiliated Sixth People's Hospital, Shanghai Jiaotong University, Shanghai, China
| | - Qiang Zhang
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Qinling Mo
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, Tianjin, China
| | - Jiafu Long
- State Key Laboratory of Medicinal Chemical Biology, Tianjin Key Laboratory of Protein Science, College of Life Sciences, Nankai University, Tianjin, China
| | - Fei Lan
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yiwen Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
- Cancer Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA.
- Neuroscience Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX, USA.
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15
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Protein Kinase C Activation Drives a Differentiation Program in an Oligodendroglial Precursor Model through the Modulation of Specific Biological Networks. Int J Mol Sci 2021; 22:ijms22105245. [PMID: 34063504 PMCID: PMC8156399 DOI: 10.3390/ijms22105245] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 05/07/2021] [Accepted: 05/12/2021] [Indexed: 02/03/2023] Open
Abstract
Protein kinase C (PKC) activation induces cellular reprogramming and differentiation in various cell models. Although many effectors of PKC physiological actions have been elucidated, the molecular mechanisms regulating oligodendrocyte differentiation after PKC activation are still unclear. Here, we applied a liquid chromatography–mass spectrometry (LC–MS/MS) approach to provide a comprehensive analysis of the proteome expression changes in the MO3.13 oligodendroglial cell line after PKC activation. Our findings suggest that multiple networks that communicate and coordinate with each other may finally determine the fate of MO3.13 cells, thus identifying a modular and functional biological structure. In this work, we provide a detailed description of these networks and their participating components and interactions. Such assembly allows perturbing each module, thus describing its physiological significance in the differentiation program. We applied this approach by targeting the Rho-associated protein kinase (ROCK) in PKC-activated cells. Overall, our findings provide a resource for elucidating the PKC-mediated network modules that contribute to a more robust knowledge of the molecular dynamics leading to this cell fate transition.
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16
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Zhou X, Shin S, He C, Zhang Q, Rasband MN, Ren J, Dai C, Zorrilla-Veloz RI, Shingu T, Yuan L, Wang Y, Chen Y, Lan F, Hu J. Qki regulates myelinogenesis through Srebp2-dependent cholesterol biosynthesis. eLife 2021; 10:60467. [PMID: 33942715 PMCID: PMC8139834 DOI: 10.7554/elife.60467] [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: 06/26/2020] [Accepted: 05/01/2021] [Indexed: 01/14/2023] Open
Abstract
Myelination depends on timely, precise control of oligodendrocyte differentiation and myelinogenesis. Cholesterol is the most abundant component of myelin and essential for myelin membrane assembly in the central nervous system. However, the underlying mechanisms of precise control of cholesterol biosynthesis in oligodendrocytes remain elusive. In the present study, we found that Qki depletion in neural stem cells or oligodendrocyte precursor cells in neonatal mice resulted in impaired cholesterol biosynthesis and defective myelinogenesis without compromising their differentiation into Aspa+Gstpi+ myelinating oligodendrocytes. Mechanistically, Qki-5 functions as a co-activator of Srebp2 to control transcription of the genes involved in cholesterol biosynthesis in oligodendrocytes. Consequently, Qki depletion led to substantially reduced concentration of cholesterol in mouse brain, impairing proper myelin assembly. Our study demonstrated that Qki-Srebp2-controlled cholesterol biosynthesis is indispensable for myelinogenesis and highlights a novel function of Qki as a transcriptional co-activator beyond its canonical function as an RNA-binding protein.
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Affiliation(s)
- Xin Zhou
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States.,Cancer Research Institute of Jilin University, The First Hospital of Jilin University, Changchun, Jilin, China
| | - Seula Shin
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States.,Cancer Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, United States
| | - Chenxi He
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Qiang Zhang
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States
| | - Matthew N Rasband
- Department of Neuroscience, Baylor College of Medicine, Houston, United States
| | - Jiangong Ren
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States
| | - Congxin Dai
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States.,Department of Neurosurgery, Beijing Tongren Hospital, Capital Medical University, Beijing, China
| | - Rocío I Zorrilla-Veloz
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States.,Cancer Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, United States
| | - Takashi Shingu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States
| | - Liang Yuan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States.,Graduate School of Biomedical Sciences, Tufts University, Boston, United States
| | - Yunfei Wang
- Clinical Science Division, H. Lee Moffitt Cancer Center & Research Institute, Tampa, United States
| | - Yiwen Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, United States
| | - Fei Lan
- Shanghai Key Laboratory of Medical Epigenetics, International Co-laboratory of Medical Epigenetics and Metabolism, Ministry of Science and Technology, Institutes of Biomedical Sciences, Fudan University, and Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Liver Cancer Institute, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, United States.,Cancer Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, United States.,Neuroscience Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, United States
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17
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Wang S, Tong X, Li C, Jin E, Su Z, Sun Z, Zhang W, Lei Z, Zhang HT. Quaking 5 suppresses TGF-β-induced EMT and cell invasion in lung adenocarcinoma. EMBO Rep 2021; 22:e52079. [PMID: 33769671 PMCID: PMC8183405 DOI: 10.15252/embr.202052079] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/28/2021] [Accepted: 03/08/2021] [Indexed: 01/01/2023] Open
Abstract
Quaking (QKI) proteins belong to the signal transduction and activation of RNA (STAR) family of RNA-binding proteins that have multiple functions in RNA biology. Here, we show that QKI-5 is dramatically decreased in metastatic lung adenocarcinoma (LUAD). QKI-5 overexpression inhibits TGF-β-induced epithelial-mesenchymal transition (EMT) and invasion, whereas QKI-5 knockdown has the opposite effect. QKI-5 overexpression and silencing suppresses and promotes TGF-β-stimulated metastasis in vivo, respectively. QKI-5 inhibits TGF-β-induced EMT and invasion in a TGFβR1-dependent manner. KLF6 knockdown increases TGFβR1 expression and promotes TGF-β-induced EMT, which is partly abrogated by QKI-5 overexpression. Mechanistically, QKI-5 directly interacts with the TGFβR1 3' UTR and causes post-transcriptional degradation of TGFβR1 mRNA, thereby inhibiting TGF-β-induced SMAD3 phosphorylation and TGF-β/SMAD signaling. QKI-5 is positively regulated by KLF6 at the transcriptional level. In LUAD tissues, KLF6 is lowly expressed and positively correlated with QKI-5 expression, while TGFβR1 expression is up-regulated and inversely correlated with QKI-5 expression. We reveal a novel mechanism by which KLF6 transcriptionally regulates QKI-5 and suggest that targeting the KLF6/QKI-5/TGFβR1 axis is a promising targeting strategy for metastatic LUAD.
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Affiliation(s)
- Shengjie Wang
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China.,Department of Basic Medicine, Kangda College of Nanjing Medical University, Lianyungang, China
| | - Xin Tong
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China
| | - Chang Li
- Department of Thoracic Surgery, The First Affiliated Hospital of Soochow University, Medical College of Soochow University, Suzhou, China
| | - Ersuo Jin
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China
| | - Zhiyue Su
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China
| | - Zelong Sun
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China
| | - Weiwei Zhang
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China
| | - Zhe Lei
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China
| | - Hong-Tao Zhang
- Soochow University Laboratory of Cancer Molecular Genetics, Medical College of Soochow University, Suzhou, China.,Department of Genetics, School of Biology and Basic Medical Sciences, Medical College of Soochow University, Suzhou, China.,Suzhou Key Laboratory for Molecular Cancer Genetics, Suzhou, Jiangsu, China
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18
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RNA Localization and Local Translation in Glia in Neurological and Neurodegenerative Diseases: Lessons from Neurons. Cells 2021; 10:cells10030632. [PMID: 33809142 PMCID: PMC8000831 DOI: 10.3390/cells10030632] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 03/03/2021] [Accepted: 03/09/2021] [Indexed: 12/11/2022] Open
Abstract
Cell polarity is crucial for almost every cell in our body to establish distinct structural and functional domains. Polarized cells have an asymmetrical morphology and therefore their proteins need to be asymmetrically distributed to support their function. Subcellular protein distribution is typically achieved by localization peptides within the protein sequence. However, protein delivery to distinct cellular compartments can rely, not only on the transport of the protein itself but also on the transport of the mRNA that is then translated at target sites. This phenomenon is known as local protein synthesis. Local protein synthesis relies on the transport of mRNAs to subcellular domains and their translation to proteins at target sites by the also localized translation machinery. Neurons and glia specially depend upon the accurate subcellular distribution of their proteome to fulfil their polarized functions. In this sense, local protein synthesis has revealed itself as a crucial mechanism that regulates proper protein homeostasis in subcellular compartments. Thus, deregulation of mRNA transport and/or of localized translation can lead to neurological and neurodegenerative diseases. Local translation has been more extensively studied in neurons than in glia. In this review article, we will summarize the state-of-the art research on local protein synthesis in neuronal function and dysfunction, and we will discuss the possibility that local translation in glia and deregulation thereof contributes to neurological and neurodegenerative diseases.
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19
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Loss of Quaking RNA binding protein disrupts the expression of genes associated with astrocyte maturation in mouse brain. Nat Commun 2021; 12:1537. [PMID: 33750804 PMCID: PMC7943582 DOI: 10.1038/s41467-021-21703-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/09/2021] [Indexed: 01/31/2023] Open
Abstract
Quaking RNA binding protein (QKI) is essential for oligodendrocyte development as myelination requires myelin basic protein mRNA regulation and localization by the cytoplasmic isoforms (e.g., QKI-6). QKI-6 is also highly expressed in astrocytes, which were recently demonstrated to have regulated mRNA localization. Here, we define the targets of QKI in the mouse brain via CLIPseq and we show that QKI-6 binds 3'UTRs of a subset of astrocytic mRNAs. Binding is also enriched near stop codons, mediated partially by QKI-binding motifs (QBMs), yet spreads to adjacent sequences. Using a viral approach for mosaic, astrocyte-specific gene mutation with simultaneous translating RNA sequencing (CRISPR-TRAPseq), we profile ribosome associated mRNA from QKI-null astrocytes in the mouse brain. This demonstrates a role for QKI in stabilizing CLIP-defined direct targets in astrocytes in vivo and further shows that QKI mutation disrupts the transcriptional changes for a discrete subset of genes associated with astrocyte maturation.
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20
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Zhou X, He C, Ren J, Dai C, Stevens SR, Wang Q, Zamler D, Shingu T, Yuan L, Chandregowda CR, Wang Y, Ravikumar V, Rao AU, Zhou F, Zheng H, Rasband MN, Chen Y, Lan F, Heimberger AB, Segal BM, Hu J. Mature myelin maintenance requires Qki to coactivate PPARβ-RXRα-mediated lipid metabolism. J Clin Invest 2021; 130:2220-2236. [PMID: 32202512 DOI: 10.1172/jci131800] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2019] [Accepted: 01/17/2020] [Indexed: 12/25/2022] Open
Abstract
Lipid-rich myelin forms electrically insulating, axon-wrapping multilayers that are essential for neural function, and mature myelin is traditionally considered metabolically inert. Surprisingly, we discovered that mature myelin lipids undergo rapid turnover, and quaking (Qki) is a major regulator of myelin lipid homeostasis. Oligodendrocyte-specific Qki depletion, without affecting oligodendrocyte survival, resulted in rapid demyelination, within 1 week, and gradually neurological deficits in adult mice. Myelin lipids, especially the monounsaturated fatty acids and very-long-chain fatty acids, were dramatically reduced by Qki depletion, whereas the major myelin proteins remained intact, and the demyelinating phenotypes of Qki-depleted mice were alleviated by a high-fat diet. Mechanistically, Qki serves as a coactivator of the PPARβ-RXRα complex, which controls the transcription of lipid-metabolism genes, particularly those involved in fatty acid desaturation and elongation. Treatment of Qki-depleted mice with PPARβ/RXR agonists significantly alleviated neurological disability and extended survival durations. Furthermore, a subset of lesions from patients with primary progressive multiple sclerosis were characterized by preferential reductions in myelin lipid contents, activities of various lipid metabolism pathways, and expression level of QKI-5 in human oligodendrocytes. Together, our results demonstrate that continuous lipid synthesis is indispensable for mature myelin maintenance and highlight an underappreciated role of lipid metabolism in demyelinating diseases.
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Affiliation(s)
- Xin Zhou
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Chenxi He
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, and Key Laboratory of Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Jiangong Ren
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Congxin Dai
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Department of Neurosurgery, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Sharon R Stevens
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Qianghu Wang
- Department of Bioinformatics, and Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Daniel Zamler
- Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
| | - Takashi Shingu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Liang Yuan
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,Graduate School of Biomedical Sciences, Tufts University, Boston, Massachusetts, USA
| | - Chythra R Chandregowda
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Yunfei Wang
- Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Visweswaran Ravikumar
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Arvind Uk Rao
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA.,Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan, USA.,Department of Biomedical Engineering, University of Michigan, Ann Arbor, Michigan, USA
| | - Feng Zhou
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, and Institutes of Biomedical Sciences, Shanghai, China
| | - Hongwu Zheng
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, USA
| | - Matthew N Rasband
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, USA
| | - Yiwen Chen
- Department of Bioinformatics and Computational Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Fei Lan
- Liver Cancer Institute, Zhongshan Hospital, Fudan University, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, and Key Laboratory of Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Amy B Heimberger
- Department of Neurosurgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA
| | - Benjamin M Segal
- Department of Neurology, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA.,The Neurological Research Institute, The Ohio State University, Columbus, Ohio, USA
| | - Jian Hu
- Department of Cancer Biology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.,The University of Texas MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, Texas, USA
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21
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Ameis D, Liu F, Kirby E, Patel D, Keijzer R. The RNA-binding protein Quaking regulates multiciliated and basal cell abundance in the developing lung. Am J Physiol Lung Cell Mol Physiol 2021; 320:L557-L567. [PMID: 33438508 DOI: 10.1152/ajplung.00481.2019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
RNA-binding proteins (RBPs) form complexes with RNA, changing how the RNA is processed and thereby regulating gene expression. RBPs are important sources of gene regulation during organogenesis, including the development of lungs. The RBP called Quaking (QK) is critical for embryogenesis, yet it has not been studied in the developing lung. Here, we show that QK is widely expressed during rat lung development and into adulthood. The QK isoforms QK5 and QK7 colocalize to the nuclei of nearly all lung cells. QK6 is present in the nuclei and cytoplasm of mesenchymal cells and is only present in the epithelium during branching morphogenesis. QK knockdown in embryonic lung explants caused a greater number of multiciliated cells to appear in the airways, at the expense of basal cells. The mRNA of multiciliated cell genes and the abundance of FOXJ1/SOX2+ cells increased after knockdown, whereas P63/SOX2+ cells decreased. The cytokine IL-6, a known regulator of multiciliated cell differentiation, had increased mRNA levels after QK knockdown, although protein levels remained unchanged. Further studies are necessary to confirm whether QK acts as a blocker for the IL-6-induced differentiation of basal cells into multiciliated cells, and a conditional QK knockout would likely lead to additional discoveries on QK's role during lung development.
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Affiliation(s)
- Dustin Ameis
- Departments of Surgery, Division of Pediatric Surgery, Pediatrics & Child Health and Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada.,Biology of Breathing Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Franklin Liu
- Departments of Surgery, Division of Pediatric Surgery, Pediatrics & Child Health and Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada.,Biology of Breathing Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Eimear Kirby
- Departments of Surgery, Division of Pediatric Surgery, Pediatrics & Child Health and Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada.,Biology of Breathing Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Daywin Patel
- Departments of Surgery, Division of Pediatric Surgery, Pediatrics & Child Health and Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada.,Biology of Breathing Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
| | - Richard Keijzer
- Departments of Surgery, Division of Pediatric Surgery, Pediatrics & Child Health and Physiology & Pathophysiology, University of Manitoba, Winnipeg, Manitoba, Canada.,Biology of Breathing Theme, Children's Hospital Research Institute of Manitoba, Winnipeg, Manitoba, Canada
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22
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LncRNA DANCR represses Doxorubicin-induced apoptosis through stabilizing MALAT1 expression in colorectal cancer cells. Cell Death Dis 2021; 12:24. [PMID: 33414433 PMCID: PMC7791116 DOI: 10.1038/s41419-020-03318-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/02/2020] [Accepted: 12/04/2020] [Indexed: 12/12/2022]
Abstract
Long non-coding RNA (lncRNA) DANCR has been reported to participate in key processes such as stem cell differentiation and tumorigenesis. In a high throughput screening for lncRNAs involved in Doxorubicin-induced apoptosis, we found DANCR was suppressed by Doxorubicin and it acted as an important repressor of apoptosis in colorectal cancer. Further studies demonstrated that DANCR promoted the oncogenic lncRNA MALAT1 expression via enhancing the RNA stability of MALAT1 to suppress apoptosis. MALAT1 could efficiently mediate the suppressive function of DANCR on apoptosis. Mechanistic studies found the RNA-binding protein QK served as an interacting partner of both DANCR and MALAT1, and the protein level of QK was subjected to the regulation by DANCR. Furthermore, QK was able to modulate the RNA stability of MALAT1, and the interaction between QK and MALAT1 was controlled by DANCR. In addition, QK could mediate the function of DANCR in regulating the expression of MALAT1 and suppressing apoptosis. These results revealed DANCR played a critical role in Doxorubicin-induced apoptosis in colorectal cancer cells, which was achieved by the interaction between DANCR and QK to enhance the expression of MALAT1.
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23
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Rauwel B, Degboé Y, Diallo K, Sayegh S, Baron M, Boyer JF, Constantin A, Cantagrel A, Davignon JL. Inhibition of Osteoclastogenesis by the RNA-Binding Protein QKI5: a Novel Approach to Protect from Bone Resorption. J Bone Miner Res 2020; 35:753-765. [PMID: 31834954 DOI: 10.1002/jbmr.3943] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 11/26/2019] [Accepted: 11/29/2019] [Indexed: 12/12/2022]
Abstract
Increased osteoclastogenesis is a common feature of bone erosion, notably in osteoporosis but also in inflammatory diseases such as rheumatoid arthritis (RA) and osteoarticular infections. Human cytomegalovirus (HCMV) infection has been described to impair monocyte differentiation into macrophages and dendritic cells. However, its effect on monocyte-derived osteoclasts is yet to be determined. We showed here that in vitro HCMV infection is associated with an inhibition of osteoclastogenesis through decreased expression of colony stimulating factor 1 receptor (CSF-1R) and RANK in monocytes, which was mediated by an upregulation of quaking I-5 protein (QKI-5), a cellular RNA-interacting protein. We found that deliberate QKI5 overexpression in the absence of HCMV infection is able to decrease CSF-1R and RANK expression, leading to osteoclastogenesis inhibition. Finally, by using lentiviral vectors in a calvarial bone erosion mouse model, we showed that QKI5 inhibits bone degradation. This work identifies QKI5 as a strong inhibitor of bone resorption. Future research will point out whether QKI5 could be a target for bone pathologies. © 2019 American Society for Bone and Mineral Research.
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Affiliation(s)
- Benjamin Rauwel
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France
| | - Yannick Degboé
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France.,Centre de Rhumatologie, CHU de Toulouse, Toulouse, France.,Faculté de Médecine, Université Paul Sabatier Toulouse III, Toulouse, France
| | - Katy Diallo
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France
| | - Souraya Sayegh
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France
| | - Michel Baron
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France
| | - Jean-Frédéric Boyer
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France.,Centre de Rhumatologie, CHU de Toulouse, Toulouse, France
| | - Arnaud Constantin
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France.,Centre de Rhumatologie, CHU de Toulouse, Toulouse, France.,Faculté de Médecine, Université Paul Sabatier Toulouse III, Toulouse, France
| | - Alain Cantagrel
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France.,Centre de Rhumatologie, CHU de Toulouse, Toulouse, France.,Faculté de Médecine, Université Paul Sabatier Toulouse III, Toulouse, France
| | - Jean-Luc Davignon
- Centre de Physiopathologie Toulouse Purpan, INSERM UMR 1043, Toulouse, France.,Centre de Rhumatologie, CHU de Toulouse, Toulouse, France
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24
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Lu H, Ye Z, Zhai Y, Wang L, Liu Y, Wang J, Zhang W, Luo W, Lu Z, Chen J. QKI regulates adipose tissue metabolism by acting as a brake on thermogenesis and promoting obesity. EMBO Rep 2020; 21:e47929. [PMID: 31868295 PMCID: PMC6944952 DOI: 10.15252/embr.201947929] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 10/22/2019] [Accepted: 11/08/2019] [Indexed: 12/31/2022] Open
Abstract
Adipose tissue controls numerous physiological processes, and its dysfunction has a causative role in the development of systemic metabolic disorders. The role of posttranscriptional regulation in adipose metabolism has yet to be fully understood. Here, we show that the RNA-binding protein quaking (QKI) plays an important role in controlling metabolic homeostasis of the adipose tissue. QKI-deficient mice are resistant to high-fat-diet (HFD)-induced obesity. Additionally, QKI depletion increased brown fat energy dissipation and browning of subcutaneous white fat. Adipose tissue-specific depletion of QKI in mice enhances cold-induced thermogenesis, thereby preventing hypothermia in response to cold stimulus. Further mechanistic analysis reveals that QKI is transcriptionally induced by the cAMP-cAMP response element-binding protein (CREB) axis and restricts adipose tissue energy consumption by decreasing stability, nuclear export, and translation of mRNAs encoding UCP1 and PGC1α. These findings extend our knowledge of the significance of posttranscriptional regulation in adipose metabolic homeostasis and provide a potential therapeutic target to defend against obesity and its related metabolic diseases.
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Affiliation(s)
- Huanyu Lu
- Department of Occupational and Environmental Healththe Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthFourth Military Medical UniversityXi'anChina
| | - Zichen Ye
- State Key Laboratory of Cancer BiologyDepartment of PharmacogenomicsSchool of PharmacyFourth Military Medical UniversityXi'anChina
| | - Yue Zhai
- Department of Cell BiologyFourth Military Medical UniversityXi'anChina
| | - Li Wang
- State Key Laboratory of Cancer BiologyDepartment of PharmacogenomicsSchool of PharmacyFourth Military Medical UniversityXi'anChina
| | - Ying Liu
- Department of Occupational and Environmental Healththe Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthFourth Military Medical UniversityXi'anChina
| | - Jiye Wang
- Department of Occupational and Environmental Healththe Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthFourth Military Medical UniversityXi'anChina
| | - Wenbin Zhang
- Department of Occupational and Environmental Healththe Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthFourth Military Medical UniversityXi'anChina
| | - Wenjing Luo
- Department of Occupational and Environmental Healththe Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthFourth Military Medical UniversityXi'anChina
| | - Zifan Lu
- State Key Laboratory of Cancer BiologyDepartment of PharmacogenomicsSchool of PharmacyFourth Military Medical UniversityXi'anChina
| | - Jingyuan Chen
- Department of Occupational and Environmental Healththe Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational EnvironmentSchool of Public HealthFourth Military Medical UniversityXi'anChina
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25
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Lavon I, Leykin I, Charbit H, Binyamin O, Brill L, Ovadia H, Vaknin-Dembinsky A. QKI-V5 is downregulated in CNS inflammatory demyelinating diseases. Mult Scler Relat Disord 2019; 39:101881. [PMID: 31835207 DOI: 10.1016/j.msard.2019.101881] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 11/25/2019] [Accepted: 11/30/2019] [Indexed: 12/19/2022]
Abstract
BACKGROUND Neuromyelitis-optica (NMO) and multiple-sclerosis (MS) are inflammatory- demyelinating-diseases of the central-nervous-system (CNS). In a previous study, we identified 17 miRNAs that were significantly upregulated in the peripheral blood of patients with NMO, relative to healthy controls (HCs). Target gene analysis have demonstrated that QKI is targeted by 70% of the upregulated miRNAs. QKI gene encodes for a RNA-binding-protein that plays a central role in myelination. QKI variants 5, 6, 7 (QKI-V5, QKI-V6, QKI-V7) are generated via alternative splicing. Given the role played by QKI in myelination we aimed to study the expression levels of QKI variants in the circulation of patients with NMO and MS and in the circulation and brain tissue of mice-model to CNS-inflammatory-demyelinating-disease. METHODS RNA and protein expression levels of QKI variants QKI-V5, QKI-V6 and QKI-V7 were determined in the blood of patients with NMO (n = 23) or MS (n = 13). The effect of sera from patients on the expression of QKI in normal peripheral-blood-mononuclear-cells (PBMCs) or glial cells was explored. The mog-experimental-autoimmune-encephalomyelitis (EAE) mouse model was used to study the correlation between the changes in the expression levels of QKI in the blood to those in the brain. RESULTS RNA and protein expression of QKI-V5 was decreased in the peripheral blood of patients with NMO and multiple-sclerosis. Incubation of normal peripheral-blood-mononuclear-cells or glial cells with sera of patients significantly reduced the expression of QKI-V5. The blood and brain of EAE mice exhibited a corresponding decrease in QKI-V5 expression. CONCLUSION The downregulation in the expression of QKI-V5 in the blood of patients with CNS-inflammatory-demyelinating-diseases and in the brain and blood of EAE mice is likely caused by a circulating factor and might promote re-myelination by regulation of myelin-associated genes. Key words: QKI variants, Multiple sclerosis (MS), Neuromyelitis optica (NMO), Astrocytes, Demyelination.
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Affiliation(s)
- Iris Lavon
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel; Leslie and Michael Center for Neuro-oncology, Hadassah-Medical Center, Jerusalem, Israel.
| | - Ina Leykin
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel; Leslie and Michael Center for Neuro-oncology, Hadassah-Medical Center, Jerusalem, Israel
| | - Hanna Charbit
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel; Leslie and Michael Center for Neuro-oncology, Hadassah-Medical Center, Jerusalem, Israel
| | - Orli Binyamin
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel
| | - Livnat Brill
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel
| | - Haim Ovadia
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel
| | - Adi Vaknin-Dembinsky
- Department of Neurology, the Agnes-Ginges Center for Neurogenetics, Hadassah- Medical Center, Hebrew University, Jerusalem, Israel
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26
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Hojo H, Yashiro Y, Noda Y, Ogami K, Yamagishi R, Okada S, Hoshino SI, Suzuki T. The RNA-binding protein QKI-7 recruits the poly(A) polymerase GLD-2 for 3' adenylation and selective stabilization of microRNA-122. J Biol Chem 2019; 295:390-402. [PMID: 31792053 DOI: 10.1074/jbc.ra119.011617] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2019] [Revised: 11/15/2019] [Indexed: 12/21/2022] Open
Abstract
MicroRNA-122 (miR-122) is highly expressed in hepatocytes, where it plays an important role in regulating cholesterol and fatty acid metabolism, and it is also a host factor required for hepatitis C virus replication. miR-122 is selectively stabilized by 3' adenylation mediated by the cytoplasmic poly(A) polymerase GLD-2 (also known as PAPD4 or TENT2). However, it is unclear how GLD-2 specifically stabilizes miR-122. Here, we show that QKI7 KH domain-containing RNA binding (QKI-7), one of three isoforms of the QKI proteins, which are members of the signal transduction and activation of RNA (STAR) family of RNA-binding proteins, is involved in miR-122 stabilization. QKI down-regulation specifically decreased the steady-state level of mature miR-122, but did not affect the pre-miR-122 level. We also found that QKI-7 uses its C-terminal region to interact with GLD-2 and its QUA2 domain to associate with the RNA-induced silencing complex protein Argonaute 2 (Ago2), indicating that the GLD-2-QKI-7 interaction recruits GLD-2 to Ago2. QKI-7 exhibited specific affinity to miR-122 and significantly promoted GLD-2-mediated 3' adenylation of miR-122 in vitro Taken together, our findings indicate that miR-122 binds Ago2-interacting QKI-7, which recruits GLD-2 for 3' adenylation and stabilization of miR-122.
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Affiliation(s)
- Hiroaki Hojo
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yuka Yashiro
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Yuta Noda
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Koichi Ogami
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Ryota Yamagishi
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Shunpei Okada
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Shin-Ichi Hoshino
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Nagoya City University, Nagoya 467-8603, Japan
| | - Tsutomu Suzuki
- Department of Chemistry and Biotechnology, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
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27
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Barton SK, Gregory JM, Chandran S, Turner BJ. Could an Impairment in Local Translation of mRNAs in Glia be Contributing to Pathogenesis in ALS? Front Mol Neurosci 2019; 12:124. [PMID: 31164803 PMCID: PMC6536688 DOI: 10.3389/fnmol.2019.00124] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Accepted: 04/26/2019] [Indexed: 12/13/2022] Open
Abstract
One of the key pathways implicated in amyotrophic lateral sclerosis (ALS) pathogenesis is abnormal RNA processing. Studies to date have focussed on defects in RNA stability, splicing, and translation, but this review article will focus on the largely overlooked RNA processing mechanism of RNA trafficking, with particular emphasis on the importance of glia. In the central nervous system (CNS), oligodendrocytes can extend processes to myelinate and metabolically support up to 50 axons and astrocytes can extend processes to cover up to 100,000 synapses, all with differing local functional requirements. Furthermore, many of the proteins required in these processes are large, aggregation-prone proteins which would be difficult to transport in their fully translated, terminally-folded state. This, therefore, highlights a critical requirement in these cells for local control of protein translation, which is achieved through specific trafficking of mRNAs to each process and local translation therein. Given that a large number of RNA-binding proteins have been implicated in ALS, and RNA-binding proteins are essential for trafficking mRNAs from the nucleus to glial processes for local translation, RNA misprocessing in glial cells is a likely source of cellular dysfunction in ALS. To date, neurons have been the focus of ALS research, but an intrinsic deficit in glia, namely astrocytes and oligodendrocytes, could have an additive effect on declining neuronal function in ALS. This review article aims to highlight the key evidence that supports the contention that RNA trafficking deficits in astrocytes and oligodendrocytes may contribute to in ALS.
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Affiliation(s)
- Samantha K Barton
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia.,Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, United Kingdom.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Jenna M Gregory
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, United Kingdom.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom.,UK Dementia Research Institute at University of Edinburgh, Edinburgh, United Kingdom
| | - Siddharthan Chandran
- Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, United Kingdom.,Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, United Kingdom.,UK Dementia Research Institute at University of Edinburgh, Edinburgh, United Kingdom
| | - Bradley J Turner
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, Australia
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28
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Quaking orchestrates a post-transcriptional regulatory network of endothelial cell cycle progression critical to angiogenesis and metastasis. Oncogene 2019; 38:5191-5210. [PMID: 30918328 DOI: 10.1038/s41388-019-0786-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Revised: 03/01/2019] [Accepted: 03/07/2019] [Indexed: 01/03/2023]
Abstract
Angiogenesis is critical to cancer development and metastasis. However, anti-angiogenic agents have only had modest therapeutic success, partly due to an incomplete understanding of tumor endothelial cell (EC) biology. We previously reported that the microRNA (miR)-200 family inhibits metastasis through regulation of tumor angiogenesis, but the underlying molecular mechanisms are poorly characterized. Here, using integrated bioinformatics approaches, we identified the RNA-binding protein (RBP) quaking (QKI) as a leading miR-200b endothelial target with previously unappreciated roles in the tumor microenvironment in lung cancer. In lung cancer samples, both miR-200b suppression and QKI overexpression corresponded with tumor ECs relative to normal ECs, and QKI silencing phenocopied miR-200b-mediated inhibition of sprouting. Additionally, both cancer cell and endothelial QKI expression in patient samples significantly corresponded with poor survival and correlated with angiogenic indices. QKI supported EC function by stabilizing cyclin D1 (CCND1) mRNA to promote EC G1/S cell cycle transition and proliferation. Both nanoparticle-mediated RNA interference of endothelial QKI expression and palbociclib blockade of CCND1 function potently inhibited metastasis in concert with significant effects on tumor vasculature. Altogether, this work demonstrates the clinical relevance and therapeutic potential of a novel, actionable miR/RBP axis in tumor angiogenesis and metastasis.
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29
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Shi Q, Saifetiarova J, Taylor AM, Bhat MA. mTORC1 Activation by Loss of Tsc1 in Myelinating Glia Causes Downregulation of Quaking and Neurofascin 155 Leading to Paranodal Domain Disorganization. Front Cell Neurosci 2018; 12:201. [PMID: 30050412 PMCID: PMC6052123 DOI: 10.3389/fncel.2018.00201] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Accepted: 06/20/2018] [Indexed: 11/29/2022] Open
Abstract
Mutations in human tuberous sclerosis complex (TSC) genes TSC1 and TSC2 are the leading causes of developmental brain abnormalities and large tumors in other tissues. Murine Tsc1/2 have been shown to negatively regulate the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway in most tissues, and this pathway has been shown to be essential for proper oligodendrocytes/Schwann cell differentiation and myelination. Here, we report that ablation of Tsc1 gene specifically in oligodendrocytes/Schwann cells activates mTORC1 signaling resulting in severe motor disabilities, weight loss, and early postnatal death. The mutant mice of either sex showed reduced myelination, disrupted paranodal domains in myelinated axons, and disorganized unmyelinated Remak bundles. mRNA and protein expression analyses revealed strong reduction in the RNA-binding protein Quaking (Qk) and the 155 kDa glial Neurofascin (NfascNF155). Re-introduction of exogenous Qk gene in Tsc1 mutant oligodendrocytes restored NfascNF155 protein levels indicating that Qk is required for the stabilization of NfascNF155 mRNA. Interestingly, injection of Rapamycin, a pharmacological mTORC1 inhibitor, to pregnant mothers increased the lifespan of the mutant offspring, restored myelination as well as the levels of Qk and NfascNF155, and consequently the organization of the paranodal domains. Together our studies show a critical role of mTORC1 signaling in the differentiation of myelinating glial cells and proper organization of axonal domains and provide insights into TSC-associated myelinated axon abnormalities.
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Affiliation(s)
| | | | | | - Manzoor A. Bhat
- Department of Cellular and Integrative Physiology, School of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
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30
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Hoch-Kraft P, White R, Tenzer S, Krämer-Albers EM, Trotter J, Gonsior C. Dual role of the RNA helicase DDX5 in post-transcriptional regulation of Myelin Basic Protein in oligodendrocytes. J Cell Sci 2018; 131:jcs.204750. [DOI: 10.1242/jcs.204750] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 03/28/2018] [Indexed: 01/11/2023] Open
Abstract
In the central nervous system, oligodendroglial expression of Myelin Basic Protein (MBP) is crucial for the assembly and structure of the myelin sheath. MBP synthesis is tightly regulated in space and time, particularly on the post-transcriptional level. We have identified the DEAD-box RNA helicase DDX5 (alias p68) in a complex with Mbp mRNA in oligodendroglial cells. Expression of DDX5 is highest in progenitor cells and immature oligodendrocytes, where it localizes to heterogeneous populations of cytoplasmic ribonucleoprotein (RNP) complexes associated with Mbp mRNA in the cell body and processes. Manipulation of DDX5 protein amounts inversely affects levels of MBP protein. We present evidence that DDX5 is involved in post-transcriptional regulation of MBP protein synthesis, with implications for oligodendroglial development. In addition, DDX5 knockdown results in an increased abundance of MBP exon 2-positive isoforms in immature oligodendrocytes, most likely by regulating alternative splicing of Mbp. Our findings contribute to the understanding of the complex nature of MBP post-transcriptional control in immature oligodendrocytes where DDX5 appears to affect the abundance of MBP proteins via distinct but converging mechanisms.
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Affiliation(s)
- Peter Hoch-Kraft
- Molecular Cell Biology, Institute for Developmental Biology and Neurobiology, Johannes Gutenberg-University of Mainz, Anselm-Franz-von-Bentzelweg 3, 55128 Mainz, Germany
| | - Robin White
- Molecular Cell Biology, Institute for Developmental Biology and Neurobiology, Johannes Gutenberg-University of Mainz, Anselm-Franz-von-Bentzelweg 3, 55128 Mainz, Germany
- Institute of Physiology and Pathophysiology, University Medical Center of the Johannes Gutenberg-University, Duesbergweg 6, 55128 Mainz, Germany
| | - Stefan Tenzer
- Institute for Immunology, University Medical Center Mainz, Langenbeckstr. 1, 55131 Mainz, Germany
| | - Eva-Maria Krämer-Albers
- Molecular Cell Biology, Institute for Developmental Biology and Neurobiology, Johannes Gutenberg-University of Mainz, Anselm-Franz-von-Bentzelweg 3, 55128 Mainz, Germany
| | - Jacqueline Trotter
- Molecular Cell Biology, Institute for Developmental Biology and Neurobiology, Johannes Gutenberg-University of Mainz, Anselm-Franz-von-Bentzelweg 3, 55128 Mainz, Germany
| | - Constantin Gonsior
- Molecular Cell Biology, Institute for Developmental Biology and Neurobiology, Johannes Gutenberg-University of Mainz, Anselm-Franz-von-Bentzelweg 3, 55128 Mainz, Germany
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31
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Hayakawa-Yano Y, Suyama S, Nogami M, Yugami M, Koya I, Furukawa T, Zhou L, Abe M, Sakimura K, Takebayashi H, Nakanishi A, Okano H, Yano M. An RNA-binding protein, Qki5, regulates embryonic neural stem cells through pre-mRNA processing in cell adhesion signaling. Genes Dev 2017; 31:1910-1925. [PMID: 29021239 PMCID: PMC5693031 DOI: 10.1101/gad.300822.117] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 09/14/2017] [Indexed: 01/07/2023]
Abstract
Cell type-specific transcriptomes are enabled by the action of multiple regulators, which are frequently expressed within restricted tissue regions. In the present study, we identify one such regulator, Quaking 5 (Qki5), as an RNA-binding protein (RNABP) that is expressed in early embryonic neural stem cells and subsequently down-regulated during neurogenesis. mRNA sequencing analysis in neural stem cell culture indicates that Qki proteins play supporting roles in the neural stem cell transcriptome and various forms of mRNA processing that may result from regionally restricted expression and subcellular localization. Also, our in utero electroporation gain-of-function study suggests that the nuclear-type Qki isoform Qki5 supports the neural stem cell state. We next performed in vivo transcriptome-wide protein-RNA interaction mapping to search for direct targets of Qki5 and elucidate how Qki5 regulates neural stem cell function. Combined with our transcriptome analysis, this mapping analysis yielded a bona fide map of Qki5-RNA interaction at single-nucleotide resolution, the identification of 892 Qki5 direct target genes, and an accurate Qki5-dependent alternative splicing rule in the developing brain. Last, our target gene list provides the first compelling evidence that Qki5 is associated with specific biological events; namely, cell-cell adhesion. This prediction was confirmed by histological analysis of mice in which Qki proteins were genetically ablated, which revealed disruption of the apical surface of the lateral wall in the developing brain. These data collectively indicate that Qki5 regulates communication between neural stem cells by mediating numerous RNA processing events and suggest new links between splicing regulation and neural stem cell states.
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Affiliation(s)
- Yoshika Hayakawa-Yano
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8510, Japan
| | - Satoshi Suyama
- Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Masahiro Nogami
- Shonan Incubation Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa 251-8555, Japan.,Integrated Technology Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa 251-8555, Japan
| | - Masato Yugami
- Shonan Incubation Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa 251-8555, Japan.,Integrated Technology Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa 251-8555, Japan
| | - Ikuko Koya
- Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Takako Furukawa
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8510, Japan
| | - Li Zhou
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8585, Japan
| | - Manabu Abe
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8585, Japan
| | - Kenji Sakimura
- Department of Cellular Neurobiology, Brain Research Institute, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8585, Japan
| | - Hirohide Takebayashi
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8510, Japan
| | - Atsushi Nakanishi
- Shonan Incubation Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa 251-8555, Japan.,Integrated Technology Research Laboratories, Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, Fujisawa, Kanagawa 251-8555, Japan
| | - Hideyuki Okano
- Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
| | - Masato Yano
- Division of Neurobiology and Anatomy, Graduate School of Medical and Dental Sciences, Niigata University, Asahimachidori, Chuo-ku, Niigata, Niigata 951-8510, Japan.,Department of Physiology, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
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32
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Fagg WS, Liu N, Fair JH, Shiue L, Katzman S, Donohue JP, Ares M. Autogenous cross-regulation of Quaking mRNA processing and translation balances Quaking functions in splicing and translation. Genes Dev 2017; 31:1894-1909. [PMID: 29021242 PMCID: PMC5695090 DOI: 10.1101/gad.302059.117] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 09/11/2017] [Indexed: 12/18/2022]
Abstract
Quaking protein isoforms arise from a single Quaking gene and bind the same RNA motif to regulate splicing, translation, decay, and localization of a large set of RNAs. However, the mechanisms by which Quaking expression is controlled to ensure that appropriate amounts of each isoform are available for such disparate gene expression processes are unknown. Here we explore how levels of two isoforms, nuclear Quaking-5 (Qk5) and cytoplasmic Qk6, are regulated in mouse myoblasts. We found that Qk5 and Qk6 proteins have distinct functions in splicing and translation, respectively, enforced through differential subcellular localization. We show that Qk5 and Qk6 regulate distinct target mRNAs in the cell and act in distinct ways on their own and each other's transcripts to create a network of autoregulatory and cross-regulatory feedback controls. Morpholino-mediated inhibition of Qk translation confirms that Qk5 controls Qk RNA levels by promoting accumulation and alternative splicing of Qk RNA, whereas Qk6 promotes its own translation while repressing Qk5. This Qk isoform cross-regulatory network responds to additional cell type and developmental controls to generate a spectrum of Qk5/Qk6 ratios, where they likely contribute to the wide range of functions of Quaking in development and cancer.
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Affiliation(s)
- W Samuel Fagg
- Sinsheimer Laboratories, Department of Molecular, Cell, and Developmental Biology, Center for Molecular Biology of RNA, University of California at Santa Cruz. Santa Cruz, California 95064, USA.,Department of Surgery, Transplant Division, Shriners Hospital for Children, University of Texas Medical Branch, Galveston, Texas 77555, USA
| | - Naiyou Liu
- Department of Surgery, Transplant Division, Shriners Hospital for Children, University of Texas Medical Branch, Galveston, Texas 77555, USA
| | - Jeffrey Haskell Fair
- Department of Surgery, Transplant Division, Shriners Hospital for Children, University of Texas Medical Branch, Galveston, Texas 77555, USA
| | - Lily Shiue
- Sinsheimer Laboratories, Department of Molecular, Cell, and Developmental Biology, Center for Molecular Biology of RNA, University of California at Santa Cruz. Santa Cruz, California 95064, USA
| | - Sol Katzman
- Sinsheimer Laboratories, Department of Molecular, Cell, and Developmental Biology, Center for Molecular Biology of RNA, University of California at Santa Cruz. Santa Cruz, California 95064, USA
| | - John Paul Donohue
- Sinsheimer Laboratories, Department of Molecular, Cell, and Developmental Biology, Center for Molecular Biology of RNA, University of California at Santa Cruz. Santa Cruz, California 95064, USA
| | - Manuel Ares
- Sinsheimer Laboratories, Department of Molecular, Cell, and Developmental Biology, Center for Molecular Biology of RNA, University of California at Santa Cruz. Santa Cruz, California 95064, USA
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33
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Sharma M, Anirudh CR. Mechanism of mRNA-STAR domain interaction: Molecular dynamics simulations of Mammalian Quaking STAR protein. Sci Rep 2017; 7:12567. [PMID: 28974714 PMCID: PMC5626755 DOI: 10.1038/s41598-017-12930-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 09/20/2017] [Indexed: 01/08/2023] Open
Abstract
STAR proteins are evolutionary conserved mRNA-binding proteins that post-transcriptionally regulate gene expression at all stages of RNA metabolism. These proteins possess conserved STAR domain that recognizes identical RNA regulatory elements as YUAAY. Recently reported crystal structures show that STAR domain is composed of N-terminal QUA1, K-homology domain (KH) and C-terminal QUA2, and mRNA binding is mediated by KH-QUA2 domain. Here, we present simulation studies done to investigate binding of mRNA to STAR protein, mammalian Quaking protein (QKI). We carried out conventional MD simulations of STAR domain in presence and absence of mRNA, and studied the impact of mRNA on the stability, dynamics and underlying allosteric mechanism of STAR domain. Our unbiased simulations results show that presence of mRNA stabilizes the overall STAR domain by reducing the structural deviations, correlating the ‘within-domain’ motions, and maintaining the native contacts information. Absence of mRNA not only influenced the essential modes of motion of STAR domain, but also affected the connectivity of networks within STAR domain. We further explored the dissociation of mRNA from STAR domain using umbrella sampling simulations, and the results suggest that mRNA binding to STAR domain occurs in multi-step: first conformational selection of mRNA backbone conformations, followed by induced fit mechanism as nucleobases interact with STAR domain.
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Affiliation(s)
- Monika Sharma
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Sector 81, Knowledge City, SAS Nagar, Punjab, India.
| | - C R Anirudh
- Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER), Sector 81, Knowledge City, SAS Nagar, Punjab, India
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34
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RNA binding protein QKI contributes to WT1 mRNA and suppresses apoptosis in ST cells. Genes Genomics 2017. [DOI: 10.1007/s13258-017-0560-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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35
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Bonnet A, Lambert G, Ernest S, Dutrieux FX, Coulpier F, Lemoine S, Lobbardi R, Rosa FM. Quaking RNA-Binding Proteins Control Early Myofibril Formation by Modulating Tropomyosin. Dev Cell 2017; 42:527-541.e4. [PMID: 28867488 DOI: 10.1016/j.devcel.2017.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 06/26/2017] [Accepted: 08/03/2017] [Indexed: 10/24/2022]
Abstract
Skeletal muscle contraction is mediated by myofibrils, complex multi-molecular scaffolds structured into repeated units, the sarcomeres. Myofibril structure and function have been extensively studied, but the molecular processes regulating its formation within the differentiating muscle cell remain largely unknown. Here we show in zebrafish that genetic interference with the Quaking RNA-binding proteins disrupts the initial steps of myofibril assembly without affecting early muscle differentiation. Using RNA sequencing, we demonstrate that Quaking is required for accumulation of the muscle-specific tropomyosin-3 transcript, tpm3.12. Further functional analyses reveal that Tpm3.12 mediates Quaking control of myofibril formation. Moreover, we identified a Quaking-binding site in the 3' UTR of tpm3.12 transcript, which is required in vivo for tpm3.12 accumulation and myofibril formation. Our work uncovers a Quaking/Tpm3 pathway controlling de novo myofibril assembly. This unexpected developmental role for Tpm3 could be at the origin of muscle defects observed in human congenital myopathies associated with tpm3 mutation.
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Affiliation(s)
- Aline Bonnet
- IBENS, Institut de Biologie de l'Ecole Normale Supérieure, 75005 Paris, France; INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France.
| | - Guillaume Lambert
- IBENS, Institut de Biologie de l'Ecole Normale Supérieure, 75005 Paris, France; INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France
| | - Sylvain Ernest
- IBENS, Institut de Biologie de l'Ecole Normale Supérieure, 75005 Paris, France; INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France
| | - François Xavier Dutrieux
- IBENS, Institut de Biologie de l'Ecole Normale Supérieure, 75005 Paris, France; INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France
| | - Fanny Coulpier
- INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France; IBENS, Institut de Biologie de l'Ecole Normale Supérieure, Plateforme Génomique, 75005 Paris, France
| | - Sophie Lemoine
- INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France; IBENS, Institut de Biologie de l'Ecole Normale Supérieure, Plateforme Génomique, 75005 Paris, France
| | - Riadh Lobbardi
- IBENS, Institut de Biologie de l'Ecole Normale Supérieure, 75005 Paris, France; INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France
| | - Frédéric Marc Rosa
- IBENS, Institut de Biologie de l'Ecole Normale Supérieure, 75005 Paris, France; INSERM U1024, 75005 Paris, France; CNRS UMR 8197, 75005 Paris, France.
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36
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Transcriptome profiling of mouse brains with qkI-deficient oligodendrocytes reveals major alternative splicing defects including self-splicing. Sci Rep 2017; 7:7554. [PMID: 28790308 PMCID: PMC5548867 DOI: 10.1038/s41598-017-06211-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Accepted: 06/08/2017] [Indexed: 12/31/2022] Open
Abstract
The qkI gene encodes a family of RNA binding proteins alternatively spliced at its 3′ end, giving rise to three major spliced isoforms: QKI-5, QKI-6 and QKI-7. Their expression is tightly regulated during brain development with nuclear QKI-5 being the most abundant during embryogenesis followed by QKI-6 and QKI-7 that peak during myelination. Previously, we generated a mouse conditional qkI allele where exon 2 is excised using Olig2-Cre resulting in QKI-deficient oligodendrocytes (OLs). These mice have dysmyelination and die at the third post-natal week. Herein, we performed a transcriptomic analysis of P14 mouse brains of QKI-proficient (QKIFL/FL;-) and QKI-deficient (QKIFL/FL;Olig2-Cre) OLs. QKI deficiency results in major global changes of gene expression and RNA processing with >1,800 differentially expressed genes with the top categories being axon ensheathment and myelination. Specific downregulated genes included major myelin proteins, suggesting that the QKI proteins are key regulators of RNA metabolism in OLs. We also identify 810 alternatively spliced genes including known QKI targets, MBP and Nfasc. Interestingly, we observe in QKIFL/FL;Olig2-Cre a switch in exon 2-deficient qkI mRNAs favoring the expression of the qkI-5 rather than the qkI-6 and qkI-7. These findings define QKI as regulators of alternative splicing in OLs including self-splicing.
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37
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Farnsworth B, Radomska KJ, Zimmermann B, Kettunen P, Jazin E, Emilsson LS. QKI6B mRNA levels are upregulated in schizophrenia and predict GFAP expression. Brain Res 2017; 1669:63-68. [PMID: 28552414 DOI: 10.1016/j.brainres.2017.05.027] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2017] [Revised: 05/21/2017] [Accepted: 05/22/2017] [Indexed: 01/21/2023]
Abstract
Schizophrenia is a highly heritable disorder with a heterogeneous symptomatology. Research increasingly indicates the importance of the crucial and often overlooked glial perturbations within schizophrenia. Within this study, we examined an isoform of quaking (a gene encoding an RNA-binding protein that is exclusively expressed in glial cells), known as QKI6B, and a prototypical astrocyte marker, glial fibrillary acidic protein (GFAP), postulated to be under the regulation of QKI. The expression levels of these genes were quantified across post-mortem brain samples from 55 schizophrenic individuals, and 55 healthy controls, using real-time PCR. We report, through an analysis of covariance (ANCOVA) model, an upregulation of both QKI6B, and GFAP in the prefrontal cortex of brain samples of schizophrenic individuals, as compared to control samples. Previous research has suggested that the QKI protein directly regulates the expression of several genes through interaction with a motif in the target's sequence, termed the Quaking Response Element (QRE). We therefore examined if QKI6B expression can predict the outcome of GFAP, and several oligodendrocyte-related genes, using a multiple linear regression approach. We found that QKI6B significantly predicts the expression of GFAP, but does not predict oligodendrocyte-related gene outcome, as previously seen with other QKI isoforms.
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Affiliation(s)
- B Farnsworth
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - K J Radomska
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - B Zimmermann
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - P Kettunen
- Institute of Neuroscience and Physiology, Department of Psychiatry and Neurochemistry, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden; Department of Neuropathology, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
| | - E Jazin
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - L S Emilsson
- Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden.
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38
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Jeon SJ, Ryu JH, Bahn GH. Altered Translational Control of Fragile X Mental Retardation Protein on Myelin Proteins in Neuropsychiatric Disorders. Biomol Ther (Seoul) 2017; 25:231-238. [PMID: 27829268 PMCID: PMC5424632 DOI: 10.4062/biomolther.2016.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2016] [Revised: 06/28/2016] [Accepted: 07/28/2016] [Indexed: 01/07/2023] Open
Abstract
Myelin is a specialized structure of the nervous system that both enhances electrical conductance and insulates neurons from external risk factors. In the central nervous system, polarized oligodendrocytes form myelin by wrapping processes in a spiral pattern around neuronal axons through myelin-related gene regulation. Since these events occur at a distance from the cell body, post-transcriptional control of gene expression has strategic advantage to fine-tune the overall regulation of protein contents in situ. Therefore, many research interests have been focused to identify RNA binding proteins and their regulatory mechanism in myelinating compartments. Fragile X mental retardation protein (FMRP) is one such RNA binding protein, regulating its target expression by translational control. Although the majority of works on FMRP have been performed in neurons, it is also found in the developing or mature glial cells including oligodendrocytes, where its function is not well understood. Here, we will review evidences suggesting abnormal translational regulation of myelin proteins with accompanying white matter problem and neurological deficits in fragile X syndrome, which can have wider mechanistic and pathological implication in many other neurological and psychiatric disorders.
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Affiliation(s)
- Se Jin Jeon
- Department of Life and Nanopharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Jong Hoon Ryu
- Department of Life and Nanopharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea
| | - Geon Ho Bahn
- Department of Neuropsychiatry, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea
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39
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Astrocytes locally translate transcripts in their peripheral processes. Proc Natl Acad Sci U S A 2017; 114:E3830-E3838. [PMID: 28439016 DOI: 10.1073/pnas.1617782114] [Citation(s) in RCA: 114] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Local translation in neuronal processes is key to the alteration of synaptic strength necessary for long-term potentiation, learning, and memory. Here, we present evidence that regulated de novo protein synthesis occurs within distal, perisynaptic astrocyte processes. Astrocyte ribosomal proteins are found adjacent to synapses in vivo, and immunofluorescent detection of peptide elongation in acute slices demonstrates robust translation in distal processes. We have also developed a biochemical approach to define candidate transcripts that are locally translated in astrocyte processes. Computational analyses indicate that astrocyte-localized translation is both sequence-dependent and enriched for particular biological functions, such as fatty acid synthesis, and for pathways consistent with known roles for astrocyte processes, such as GABA and glutamate metabolism. These transcripts also include glial regulators of synaptic refinement, such as Sparc Finally, the transcripts contain a disproportionate amount of a binding motif for the quaking RNA binding protein, a sequence we show can significantly regulate mRNA localization and translation in the astrocytes. Overall, our observations raise the possibility that local production of astrocyte proteins may support microscale alterations of adjacent synapses.
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40
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Thangaraj MP, Furber KL, Gan JK, Ji S, Sobchishin L, Doucette JR, Nazarali AJ. RNA-binding Protein Quaking Stabilizes Sirt2 mRNA during Oligodendroglial Differentiation. J Biol Chem 2017; 292:5166-5182. [PMID: 28188285 DOI: 10.1074/jbc.m117.775544] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Indexed: 11/06/2022] Open
Abstract
Myelination is controlled by timely expression of genes involved in the differentiation of oligodendrocyte precursor cells (OPCs) into myelinating oligodendrocytes (OLs). Sirtuin 2 (SIRT2), a NAD+-dependent deacetylase, plays a critical role in OL differentiation by promoting both arborization and downstream expression of myelin-specific genes. However, the mechanisms involved in regulating SIRT2 expression during OL development are largely unknown. The RNA-binding protein quaking (QKI) plays an important role in myelination by post-transcriptionally regulating the expression of several myelin specific genes. In quaking viable (qkv/qkv ) mutant mice, SIRT2 protein is severely reduced; however, it is not known whether these genes interact to regulate OL differentiation. Here, we report for the first time that QKI directly binds to Sirt2 mRNA via a common quaking response element (QRE) located in the 3' untranslated region (UTR) to control SIRT2 expression in OL lineage cells. This interaction is associated with increased stability and longer half-lives of Sirt2.1 and Sirt2.2 transcripts leading to increased accumulation of Sirt2 transcripts. Consistent with this, overexpression of qkI promoted the expression of Sirt2 mRNA and protein. However, overexpression of the nuclear isoform qkI-5 promoted the expression of Sirt2 mRNA, but not SIRT2 protein, and delayed OL differentiation. These results suggest that the balance in the subcellular distribution and temporal expression of QKI isoforms control the availability of Sirt2 mRNA for translation. Collectively, our study demonstrates that QKI directly plays a crucial role in the post-transcriptional regulation and expression of Sirt2 to facilitate OL differentiation.
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Affiliation(s)
- Merlin P Thangaraj
- From the Laboratory of Molecular Cell Biology, College of Pharmacy and Nutrition and.,the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Kendra L Furber
- From the Laboratory of Molecular Cell Biology, College of Pharmacy and Nutrition and.,the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Jotham K Gan
- From the Laboratory of Molecular Cell Biology, College of Pharmacy and Nutrition and.,the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Shaoping Ji
- From the Laboratory of Molecular Cell Biology, College of Pharmacy and Nutrition and.,the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.,the Department of Biochemistry and Molecular Biology, Medical School, Henan University, Kaifeng 475004, China
| | - Larhonda Sobchishin
- From the Laboratory of Molecular Cell Biology, College of Pharmacy and Nutrition and.,the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - J Ronald Doucette
- the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.,Department of Anatomy and Cell Biology, College of Medicine, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.,the Cameco Multiple Sclerosis Neuroscience Research Center, City Hospital, Saskatoon, Saskatchewan S7K 0M7, Canada, and
| | - Adil J Nazarali
- From the Laboratory of Molecular Cell Biology, College of Pharmacy and Nutrition and .,the Neuroscience Research Cluster, University of Saskatchewan, Saskatoon, Saskatchewan S7N 5E5, Canada.,the Cameco Multiple Sclerosis Neuroscience Research Center, City Hospital, Saskatoon, Saskatchewan S7K 0M7, Canada, and
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Quaking Regulates Neurofascin 155 Expression for Myelin and Axoglial Junction Maintenance. J Neurosci 2016; 36:4106-20. [PMID: 27053216 DOI: 10.1523/jneurosci.3529-15.2016] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 02/25/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED RNA binding proteins required for the maintenance of myelin and axoglial junctions are unknown. Herein, we report that deletion of the Quaking (QKI) RNA binding proteins in oligodendrocytes (OLs) using Olig2-Cre results in mice displaying rapid tremors at postnatal day 10, followed by death at postnatal week 3. Extensive CNS hypomyelination was observed as a result of OL differentiation defects during development. The QKI proteins were also required for adult myelin maintenance, because their ablation using PLP-CreERT resulted in hindlimb paralysis with immobility at ∼30 d after 4-hydroxytamoxifen injection. Moreover, deterioration of axoglial junctions of the spinal cord was observed and is consistent with a loss of Neurofascin 155 (Nfasc155) isoform that we confirmed as an alternative splice target of the QKI proteins. Our findings define roles for the QKI RNA binding proteins in myelin development and maintenance, as well as in the generation of Nfasc155 to maintain healthy axoglial junctions. SIGNIFICANCE STATEMENT Neurofascin 155 is responsible for axoglial junction formation and maintenance. Using a genetic mouse model to delete Quaking (QKI) RNA-binding proteins in oligodendrocytes, we identify QKI as the long-sought regulator of Neurofascin alternative splicing, further establishing the role of QKI in oligodendrocyte development and myelination. We establish a new role for QKI in myelin and axoglial junction maintenance using an inducible genetic mouse model that deletes QKI in mature oligodendrocytes. Loss of QKI in adult oligodendrocytes leads to phenotypes reminiscent of the experimental autoimmune encephalomyelitis mouse model with complete hindlimb paralysis and death by 30 d after induction of QKI deletion.
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42
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Msh2 deficiency leads to dysmyelination of the corpus callosum, impaired locomotion, and altered sensory function in mice. Sci Rep 2016; 6:30757. [PMID: 27476972 PMCID: PMC4967871 DOI: 10.1038/srep30757] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 07/10/2016] [Indexed: 02/08/2023] Open
Abstract
A feature in patients with constitutional DNA-mismatch repair deficiency is agenesis of the corpus callosum, the cause of which has not been established. Here we report a previously unrecognized consequence of deficiency in MSH2, a protein known primarily for its function in correcting nucleotide mismatches or insertions and deletions in duplex DNA caused by errors in DNA replication or recombination. We documented that Msh2 deficiency causes dysmyelination of the axonal projections in the corpus callosum. Evoked action potentials in the myelinated corpus callosum projections of Msh2-null mice were smaller than wild-type mice, whereas unmyelinated axons showed no difference. Msh2-null mice were also impaired in locomotive activity and had an abnormal response to heat. These findings reveal a novel pathogenic consequence of MSH2 deficiency, providing a new mechanistic hint to previously recognized neurological disorders in patients with inherited DNA-mismatch repair deficiency.
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43
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Expression of Quaking RNA-Binding Protein in the Adult and Developing Mouse Retina. PLoS One 2016; 11:e0156033. [PMID: 27196066 PMCID: PMC4873024 DOI: 10.1371/journal.pone.0156033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2015] [Accepted: 05/09/2016] [Indexed: 01/22/2023] Open
Abstract
Quaking (QKI), which belongs to the STAR family of KH domain-containing RNA-binding proteins, functions in pre-mRNA splicing, microRNA regulation, and formation of circular RNA. QKI plays critical roles in myelinogenesis in the central and peripheral nervous systems and has been implicated neuron-glia fate decision in the brain; however, neither the expression nor function of QKI in the neural retina is known. Here we report the expression of QKI RNA-binding protein in the developing and mature mouse retina. QKI was strongly expressed by Müller glial cells in both the developing and adult retina. Intriguingly, during development, QKI was expressed in early differentiating neurons, such as the horizontal and amacrine cells, and subsequently in later differentiating bipolar cells, but not in photoreceptors. Neuronal expression was uniformly weak in the adult. Among QKI isoforms (5, 6, and 7), QKI-5 was the predominantly expressed isoform in the adult retina. To study the function of QKI in the mouse retina, we examined quakingviable(qkv) mice, which have a dysmyelination phenotype that results from deficiency of QKI expression and reduced numbers of mature oligodendrocytes. In homozygous qkv mutant mice (qkv/qkv), the optic nerve expression levels of QKI-6 and 7, but not QKI-5 were reduced. In the retina of the mutant homozygote, QKI-5 levels were unchanged, and QKI-6 and 7 levels, already low, were also unaffected. We conclude that QKI is expressed in developing and adult Müller glia. QKI is additionally expressed in progenitors and in differentiating neurons during retinal development, but expression weakened or diminished during maturation. Among QKI isoforms, we found that QKI-5 predominated in the adult mouse retina. Since Müller glial cells are thought to share properties with retinal progenitor cells, our data suggest that QKI may contribute to maintaining retinal progenitors prior to differentiation into neurons. On the other hand, the expression of QKI in different retinal neurons may suggest a role in neuronal cell type specific fate determination and maturation. The data raises the possibility that QKI may function in retinal cell fate determination and maturation in both glia and neurons.
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Determination of a Comprehensive Alternative Splicing Regulatory Network and Combinatorial Regulation by Key Factors during the Epithelial-to-Mesenchymal Transition. Mol Cell Biol 2016; 36:1704-19. [PMID: 27044866 DOI: 10.1128/mcb.00019-16] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 03/28/2016] [Indexed: 12/31/2022] Open
Abstract
The epithelial-to-mesenchymal transition (EMT) is an essential biological process during embryonic development that is also implicated in cancer metastasis. While the transcriptional regulation of EMT has been well studied, the role of alternative splicing (AS) regulation in EMT remains relatively uncharacterized. We previously showed that the epithelial cell-type-specific proteins epithelial splicing regulatory proteins 1 (ESRP1) and ESRP2 are important for the regulation of many AS events that are altered during EMT. However, the contributions of the ESRPs and other splicing regulators to the AS regulatory network in EMT require further investigation. Here, we used a robust in vitro EMT model to comprehensively characterize splicing switches during EMT in a temporal manner. These investigations revealed that the ESRPs are the major regulators of some but not all AS events during EMT. We determined that the splicing factor RBM47 is downregulated during EMT and also regulates numerous transcripts that switch splicing during EMT. We also determined that Quaking (QKI) broadly promotes mesenchymal splicing patterns. Our study highlights the broad role of posttranscriptional regulation during the EMT and the important role of combinatorial regulation by different splicing factors to fine tune gene expression programs during these physiological and developmental transitions.
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Irie K, Tsujimura K, Nakashima H, Nakashima K. MicroRNA-214 Promotes Dendritic Development by Targeting the Schizophrenia-associated Gene Quaking (Qki). J Biol Chem 2016; 291:13891-904. [PMID: 27129236 DOI: 10.1074/jbc.m115.705749] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Indexed: 12/21/2022] Open
Abstract
Proper dendritic elaboration of neurons is critical for the formation of functional circuits during brain development. Defects in dendrite morphogenesis are associated with neuropsychiatric disorders, and microRNAs are emerging as regulators of aspects of neuronal maturation such as axonal and dendritic growth, spine formation, and synaptogenesis. Here, we show that miR-214 plays a pivotal role in the regulation of dendritic development. Overexpression of miR-214 increased dendrite size and complexity, whereas blocking of endogenous miR-214-3p, a mature form of miR-214, inhibited dendritic morphogenesis. We also found that miR-214-3p targets quaking (Qki), which is implicated in psychiatric diseases such as schizophrenia, through conserved target sites located in the 3'-untranslated region of Qki mRNA, thereby down-regulating Qki protein levels. Overexpression and knockdown of Qki impaired and enhanced dendritic formation, respectively. Moreover, overexpression of Qki abolished the dendritic growth induced by miR-214 overexpression. Taken together, our findings reveal a crucial role for the miR-214-Qki pathway in the regulation of neuronal dendritic development.
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Affiliation(s)
- Koichiro Irie
- From the Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
| | - Keita Tsujimura
- From the Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
| | - Hideyuki Nakashima
- From the Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
| | - Kinichi Nakashima
- From the Department of Stem Cell Biology and Medicine, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
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Darbelli L, Richard S. Emerging functions of the Quaking RNA-binding proteins and link to human diseases. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:399-412. [PMID: 26991871 DOI: 10.1002/wrna.1344] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Revised: 01/23/2016] [Accepted: 02/01/2016] [Indexed: 01/16/2023]
Abstract
RNA-binding proteins (RBPs) are essential players in RNA metabolism including key cellular processes from pre-mRNA splicing to mRNA translation. The K homology-type QUAKING RBP is emerging as a vital factor for oligodendrocytes, monocytes/macrophages, endothelial cell, and myocyte function. Interestingly, the qkI gene has now been identified as the culprit gene for a patient with intellectual disabilities and is translocated in a pediatric ganglioglioma as a fusion protein with MYB. In this review, we will focus on the emerging discoveries of the QKI proteins as well as highlight the recent advances in understanding the role of QKI in human disease pathology including myelin disorders, schizophrenia and cancer. WIREs RNA 2016, 7:399-412. doi: 10.1002/wrna.1344 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Lama Darbelli
- Terry Fox Molecular Oncology Group, Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Canada, H3T 1E2
| | - Stéphane Richard
- Terry Fox Molecular Oncology Group, Bloomfield Center for Research on Aging, Lady Davis Institute for Medical Research and Departments of Oncology and Medicine, McGill University, Montréal, Canada, H3T 1E2
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de Bruin RG, van der Veer EP, Prins J, Lee DH, Dane MJC, Zhang H, Roeten MK, Bijkerk R, de Boer HC, Rabelink TJ, van Zonneveld AJ, van Gils JM. The RNA-binding protein quaking maintains endothelial barrier function and affects VE-cadherin and β-catenin protein expression. Sci Rep 2016; 6:21643. [PMID: 26905650 PMCID: PMC4764852 DOI: 10.1038/srep21643] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 01/26/2016] [Indexed: 01/12/2023] Open
Abstract
Proper regulation of endothelial cell-cell contacts is essential for physiological functioning of the endothelium. Interendothelial junctions are actively involved in the control of vascular leakage, leukocyte diapedesis, and the initiation and progression of angiogenesis. We found that the RNA-binding protein quaking is highly expressed by endothelial cells, and that its expression was augmented by prolonged culture under laminar flow and the transcription factor KLF2 binding to the promoter. Moreover, we demonstrated that quaking directly binds to the mRNA of VE-cadherin and β-catenin and can induce mRNA translation mediated by the 3′UTR of these genes. Reduced quaking levels attenuated VE-cadherin and β-catenin expression and endothelial barrier function in vitro and resulted in increased bradykinin-induced vascular leakage in vivo. Taken together, we report that quaking is essential in maintaining endothelial barrier function. Our results provide novel insight into the importance of post-transcriptional regulation in controlling vascular integrity.
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Affiliation(s)
- Ruben G de Bruin
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Eric P van der Veer
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Jurriën Prins
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Dae Hyun Lee
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Martijn J C Dane
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Huayu Zhang
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Marko K Roeten
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Roel Bijkerk
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Hetty C de Boer
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Ton J Rabelink
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Anton Jan van Zonneveld
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - Janine M van Gils
- Einthoven Laboratory of Experimental Vascular Medicine, Division of Nephrology, Department of Internal Medicine, Leiden University Medical Center, Leiden, the Netherlands
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Myers KR, Liu G, Feng Y, Zheng JQ. Oligodendroglial defects during quakingviable cerebellar development. Dev Neurobiol 2015; 76:972-82. [PMID: 26645409 DOI: 10.1002/dneu.22369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 11/16/2015] [Accepted: 12/01/2015] [Indexed: 11/06/2022]
Abstract
The selective RNA-binding protein Quaking I (QKI) has previously been implicated in RNA localization and stabilization, alternative splicing, cell proliferation, and differentiation. The spontaneously-occurring quakingviable (qkv) mutant mouse exhibits a sharply attenuated level of QKI in myelin-producing cells, including oligodendrocytes (OL) because of the loss of an OL-specific promoter. The disruption of QKI in OLs results in severe hypomyelination of the central nervous system, but the underlying cellular mechanisms remain to be fully elucidated. In this study, we used the qkv mutant mouse as a model to study myelination defects in the cerebellum. We found that oligodendroglial development and myelination are adversely affected in the cerebellum of qkv mice. Specifically, we identified an increase in the total number of oligodendroglial precursor cells in qkv cerebella, a substantial portion of which migrated into the grey matter. Furthermore, these mislocalized oligodendroglial precursor cells retained their migratory morphology late into development. Interestingly, a number of these presumptive oligodendrocyte precursors were found at the Purkinje cell layer in qkv cerebella, resembling Bergman glia. These findings indicate that QKI is involved in multiple aspects of oligodendroglial development. QKI disruption can impact the cell fate of oligodendrocyte precursor cells, their migration and differentiation, and ultimately myelination in the cerebellum. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 972-982, 2016.
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Affiliation(s)
- Kenneth R Myers
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, 30322.,Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - Guanglu Liu
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - Yue Feng
- Department of Pharmacology, Emory University School of Medicine, Atlanta, Georgia, 30322
| | - James Q Zheng
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, 30322.,Center for Neurodegenerative Diseases, Emory University School of Medicine, Atlanta, Georgia, 30322.,Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, 30322
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Hashimoto M, Murata K, Ishida J, Kanou A, Kasuya Y, Fukamizu A. Severe Hypomyelination and Developmental Defects Are Caused in Mice Lacking Protein Arginine Methyltransferase 1 (PRMT1) in the Central Nervous System. J Biol Chem 2015; 291:2237-45. [PMID: 26637354 DOI: 10.1074/jbc.m115.684514] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Indexed: 12/24/2022] Open
Abstract
Protein arginine methyltransferase 1 (PRMT1) is involved in cell proliferation, DNA damage response, and transcriptional regulation. Although PRMT1 is extensively expressed in the CNS at embryonic and perinatal stages, the physiological role of PRMT1 has been poorly understood. Here, to investigate the primary function of PRMT1 in the CNS, we generated CNS-specific PRMT1 knock-out mice by the Cre-loxP system. These mice exhibited postnatal growth retardation with tremors, and most of them died within 2 weeks after birth. Brain histological analyses revealed prominent cell reduction in the white matter tracts of the mutant mice. Furthermore, ultrastructural analysis demonstrated that myelin sheath was almost completely ablated in the CNS of these animals. In agreement with hypomyelination, we also observed that most major myelin proteins including myelin basic protein (MBP), 2',3'-cyclic-nucleotide 3'-phosphodiesterase (CNPase), and myelin-associated glycoprotein (MAG) were dramatically decreased, although neuronal and astrocytic markers were preserved in the brain of CNS-specific PRMT1 knock-out mice. These animals had a reduced number of OLIG2(+) oligodendrocyte lineage cells in the white matter. We found that expressions of transcription factors essential for oligodendrocyte specification and further maturation were significantly suppressed in the brain of the mutant mice. Our findings provide evidence that PRMT1 is required for CNS development, especially for oligodendrocyte maturation processes.
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Affiliation(s)
- Misuzu Hashimoto
- From the Ph.D. Program in Human Biology, School of Integrative and Global Majors
| | - Kazuya Murata
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), and
| | - Junji Ishida
- Life Science Center, Tsukuba Advanced Research Alliance (TARA), and Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 and
| | - Akihiko Kanou
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 and
| | - Yoshitoshi Kasuya
- the Department of Biochemistry and Molecular Pharmacology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chiba 260-8670, Japan
| | - Akiyoshi Fukamizu
- From the Ph.D. Program in Human Biology, School of Integrative and Global Majors, Life Science Center, Tsukuba Advanced Research Alliance (TARA), and Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577 and
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50
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Wang S, Zan J, Wu M, Zhao W, Li Z, Pan Y, Sun Z, Zhu J. miR-29a promotes scavenger receptor A expression by targeting QKI (quaking) during monocyte-macrophage differentiation. Biochem Biophys Res Commun 2015; 464:1-6. [PMID: 26056009 DOI: 10.1016/j.bbrc.2015.05.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 05/07/2015] [Indexed: 12/22/2022]
Abstract
Monocyte differentiation into macrophages results in upregulation of miR-29a and scavenger receptor A (SRA) expression, while the expression of RNA binding protein, QKI is suppressed. Since SRA is a functionally important protein in atherosclerosis, it is imperative to understand the various mechanisms involved in its regulation specially the mechanism involving miR-29a. There are individual studies linking miR-29a to SRA or QKI to monocyte differentiation but there is no evidence of any linkage among them. Therefore, we intend to investigate the association among these three, if any, in terms of regulation of SRA expression. Hence, in this study, the differentiated macrophages were initially transfected with miR-29a or its inhibitor and it was shown that QKI is a direct target of mir-29a. In addition, it was also observed by bioinformatics analysis that 3'UTR in SRA mRNA has QKI binding site. So, we attempted to further understand the role of QKI in SRA regulation. The macrophages were manipulated either with overexpression of QKI or by its ablation and it was observed that QKI suppressed SRA at the transcriptional level. Moreover, with the help of luciferase reporter vector, it was shown that QKI inhibited SRA transcription by binding to QRE region in its 3'UTR mRNA. Furthermore, to link the QKI mediated regulation of SRA expression with its functional activity; we analyzed lipid uptake capacity of macrophages transfected with either ectopic OKI plasmid or ablated for QKI. It was observed that, indeed, QKI upregulation inhibits lipid uptake by repressing SRA expression. Overall, our study demonstrates that miR-29a inhibits QKI, which in turn results in upregulation of SRA and lipid uptake.
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Affiliation(s)
- Shuai Wang
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Jie Zan
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Mingjie Wu
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Wenting Zhao
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Zhenwei Li
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Yanyun Pan
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Zewei Sun
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China
| | - Jianhua Zhu
- Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, PR China.
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