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Racedo SE, Liu Y, Shi L, Zheng D, Morrow BE. Dgcr8 functions in the secondary heart field for outflow tract and right ventricle development in mammals. Dev Biol 2024; 506:72-84. [PMID: 38110169 PMCID: PMC10793380 DOI: 10.1016/j.ydbio.2023.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 10/28/2023] [Accepted: 12/11/2023] [Indexed: 12/20/2023]
Abstract
The DGCR8 gene, encoding a critical miRNA processing protein, maps within the hemizygous region in patients with 22q11.2 deletion syndrome. Most patients have malformations of the cardiac outflow tract that is derived in part from the anterior second heart field (aSHF) mesoderm. To understand the function of Dgcr8 in the aSHF, we inactivated it in mice using Mef2c-AHF-Cre. Inactivation resulted in a fully penetrant persistent truncus arteriosus and a hypoplastic right ventricle leading to lethality by E14.5. To understand the molecular mechanism for this phenotype, we performed gene expression profiling of the aSHF and the cardiac outflow tract with right ventricle in conditional null versus normal mouse littermates at stage E9.5 prior to morphology changes. We identified dysregulation of mRNA gene expression, of which some are relevant to cardiogenesis. Many pri-miRNA genes were strongly increased in expression in mutant embryos along with reduced expression of mature miRNA genes. We further examined the individual, mature miRNAs that were decreased in expression along with pri-miRNAs that were accumulated that could be direct effects due to loss of Dgcr8. Among these genes, were miR-1a, miR-133a, miR-134, miR143 and miR145a, which have known functions in heart development. These early mRNA and miRNA changes may in part, explain the first steps that lead to the resulting phenotype in Dgcr8 aSHF conditional mutant embryos.
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Affiliation(s)
- Silvia E Racedo
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Yang Liu
- Allergy, Pulmonary, and Critical Care Medicine, Vanderbilt University Medical Center, Bell Buckle, TN, USA
| | - Lijie Shi
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Deyou Zheng
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Neurology, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Bernice E Morrow
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY, USA; Departments of Pediatrics and Ob/Gyn & Population Health, USA.
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2
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Loh HY, Norman BP, Lai KS, Cheng WH, Nik Abd Rahman NMA, Mohamed Alitheen NB, Osman MA. Post-Transcriptional Regulatory Crosstalk between MicroRNAs and Canonical TGF-β/BMP Signalling Cascades on Osteoblast Lineage: A Comprehensive Review. Int J Mol Sci 2023; 24:ijms24076423. [PMID: 37047394 PMCID: PMC10094338 DOI: 10.3390/ijms24076423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 04/14/2023] Open
Abstract
MicroRNAs (miRNAs) are a family of small, single-stranded, and non-protein coding RNAs about 19 to 22 nucleotides in length, that have been reported to have important roles in the control of bone development. MiRNAs have a strong influence on osteoblast differentiation through stages of lineage commitment and maturation, as well as via controlling the activities of osteogenic signal transduction pathways. Generally, miRNAs may modulate cell stemness, proliferation, differentiation, and apoptosis by binding the 3'-untranslated regions (3'-UTRs) of the target genes, which then can subsequently undergo messenger RNA (mRNA) degradation or protein translational repression. MiRNAs manage the gene expression in osteogenic differentiation by regulating multiple signalling cascades and essential transcription factors, including the transforming growth factor-beta (TGF-β)/bone morphogenic protein (BMP), Wingless/Int-1(Wnt)/β-catenin, Notch, and Hedgehog signalling pathways; the Runt-related transcription factor 2 (RUNX2); and osterix (Osx). This shows that miRNAs are essential in regulating diverse osteoblast cell functions. TGF-βs and BMPs transduce signals and exert diverse functions in osteoblastogenesis, skeletal development and bone formation, bone homeostasis, and diseases. Herein, we highlighted the current state of in vitro and in vivo research describing miRNA regulation on the canonical TGF-β/BMP signalling, their effects on osteoblast linage, and understand their mechanism of action for the development of possible therapeutics. In this review, particular attention and comprehensive database searches are focused on related works published between the years 2000 to 2022, using the resources from PubMed, Google Scholar, Scopus, and Web of Science.
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Affiliation(s)
- Hui-Yi Loh
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Brendan P Norman
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool L7 8TX, UK
| | - Kok-Song Lai
- Health Sciences Division, Abu Dhabi Women's College, Higher Colleges of Technology, Abu Dhabi 41012, United Arab Emirates
| | - Wan-Hee Cheng
- Faculty of Health and Life Sciences, INTI International University, Persiaran Perdana BBN, Putra Nilai, Nilai 71800, Negeri Sembilan, Malaysia
| | - Nik Mohd Afizan Nik Abd Rahman
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Noorjahan Banu Mohamed Alitheen
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
| | - Mohd Azuraidi Osman
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia
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3
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Ren J, Wu Y, Wang Y, Zhao Y, Li Y, Hao S, Lin L, Zhang S, Xu X, Wang H. CtIP suppresses primary microRNA maturation and promotes metastasis of colon cancer cells in a xenograft mouse model. J Biol Chem 2021; 296:100707. [PMID: 33901493 PMCID: PMC8164041 DOI: 10.1016/j.jbc.2021.100707] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Revised: 04/15/2021] [Accepted: 04/22/2021] [Indexed: 12/30/2022] Open
Abstract
miRNAs are important regulators of eukaryotic gene expression. The post-transcriptional maturation of miRNAs is controlled by the Drosha-DiGeorge syndrome critical region gene 8 (DGCR8) microprocessor. Dysregulation of miRNA biogenesis has been implicated in the pathogenesis of human diseases, including cancers. C-terminal-binding protein-interacting protein (CtIP) is a well-known DNA repair factor that promotes the processing of DNA double-strand break (DSB) to initiate homologous recombination-mediated DSB repair. However, it was unclear whether CtIP has other unknown cellular functions. Here, we aimed to uncover the roles of CtIP in miRNA maturation and cancer cell metastasis. We found that CtIP is a potential regulatory factor that suppresses the processing of miRNA primary transcripts (pri-miRNA). CtIP directly bound to both DGCR8 and pri-miRNAs through a conserved Sae2-like domain, reduced the binding of Drosha to DGCR8 and pri-miRNA substrate, and inhibited processing activity of Drosha complex. CtIP depletion significantly increased the expression levels of a subset of mature miRNAs, including miR-302 family members that are associated with tumor progression and metastasis in several cancer types. We also found that CtIP-inhibited miRNAs, such as miR-302 family members, are not crucial for DSB repair. However, increase of miR-302b levels or loss of CtIP function severely suppressed human colon cancer cell line tumor cell metastasis in a mouse xenograft model. These studies reveal a previously unrecognized mechanism of CtIP in miRNA processing and tumor metastasis that represents a new function of CtIP in cancer.
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Affiliation(s)
- Jianping Ren
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Yan Wu
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Ya Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Yuqin Zhao
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Youhang Li
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Shuailin Hao
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Lixiu Lin
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Shuyuan Zhang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China
| | - Xingzhi Xu
- Guangdong Key Laboratory for Genome Stability & Disease Prevention and Carson International Cancer Center, Marshall Laboratory of Biomedical Engineering, China Shenzhen University School of Medicine, Shenzhen, Guangdong, China
| | - Hailong Wang
- Beijing Key Laboratory of DNA Damage Response and College of Life Sciences, Capital Normal University, Beijing, China.
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4
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Pabit SA, Chen YL, Usher ET, Cook EC, Pollack L, Showalter SA. Elucidating the Role of Microprocessor Protein DGCR8 in Bending RNA Structures. Biophys J 2020; 119:2524-2536. [PMID: 33189689 DOI: 10.1016/j.bpj.2020.10.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 10/23/2020] [Accepted: 10/30/2020] [Indexed: 10/23/2022] Open
Abstract
Although conformational dynamics of RNA molecules are potentially important in microRNA (miRNA) processing, the role of the protein binding partners in facilitating the requisite structural changes is not well understood. In previous work, we and others have demonstrated that nonduplex structural elements and the conformational flexibility they support are necessary for efficient RNA binding and cleavage by the proteins associated with the two major stages of miRNA processing. However, recent studies showed that the protein DGCR8 binds primary miRNA and duplex RNA with similar affinities. Here, we study RNA binding by a small recombinant construct of the DGCR8 protein and the RNA conformation changes that result. This construct, the DGCR8 core, contains two double-stranded RNA-binding domains (dsRBDs) and a C-terminal tail. To assess conformational changes resulting from binding, we applied small-angle x-ray scattering with contrast variation to detect conformational changes of primary-miR-16-1 in complex with the DGCR8 core. This method reports only on the RNA conformation within the complex and suggests that the protein bends the RNA upon binding. Supporting work using smFRET to study the conformation of RNA duplexes bound to the core also shows bending. Together, these studies elucidate the role of DGCR8 in interacting with RNA during the early stages of miRNA processing.
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Affiliation(s)
- Suzette A Pabit
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York
| | - Yen-Lin Chen
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York
| | - Emery T Usher
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania
| | - Erik C Cook
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York.
| | - Scott A Showalter
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania; Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania.
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5
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Benhamou RI, Vezina-Dawod S, Choudhary S, Won Wang K, Meyer SM, Yildirim I, Disney MD. Macrocyclization of a Ligand Targeting a Toxic RNA Dramatically Improves Potency. Chembiochem 2020; 21:3229-3233. [PMID: 32649032 DOI: 10.1002/cbic.202000445] [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] [Received: 07/07/2020] [Indexed: 12/21/2022]
Abstract
RNA molecules both contribute to and are causative of many human diseases. One method to perturb RNA function is to target its structure with small molecules. However, discovering bioactive ligands for RNA targets is challenging. Here, we show that the bioactivity of a linear dimeric ligand that inactivates the RNA trinucleotide repeat expansion that causes myotonic dystrophy type 1 [DM1; r(CUG)exp ] can be improved by macrocyclization. Indeed, the macrocyclic compound is ten times more potent than the linear compound for improving DM1-associated defects in cells, including in patient-derived myotubes (muscle cells). This enhancement in potency is due to the macrocycle's increased affinity and selectively for the target, which inhibit r(CUG)exp 's toxic interaction with muscleblind-like 1 (MBNL1), and its superior cell permeability. Macrocyclization could prove to be an effective way to enhance the bioactivity of modularly assembled ligands targeting RNA.
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Affiliation(s)
- Raphael I Benhamou
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Simon Vezina-Dawod
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Shruti Choudhary
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Kye Won Wang
- Department of Chemistry, Florida Atlantic University, John D. MacArthur Campus, Jupiter, FL 33458, USA
| | - Samantha M Meyer
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
| | - Ilyas Yildirim
- Department of Chemistry, Florida Atlantic University, John D. MacArthur Campus, Jupiter, FL 33458, USA
| | - Matthew D Disney
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33458, USA
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6
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Abdalla F, Singh B, Bhat HK. MicroRNAs and gene regulation in breast cancer. J Biochem Mol Toxicol 2020; 34:e22567. [DOI: 10.1002/jbt.22567] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Revised: 06/01/2020] [Accepted: 06/18/2020] [Indexed: 12/15/2022]
Affiliation(s)
- Fatma Abdalla
- Division of Pharmacology and Pharmaceutical Sciences, School of Pharmacy University of Missouri‐Kansas City Kansas City Missouri
| | - Bhupendra Singh
- Division of Pharmacology and Pharmaceutical Sciences, School of Pharmacy University of Missouri‐Kansas City Kansas City Missouri
- Eurofins Lancaster Laboratories Lancaster PA 17605
| | - Hari K. Bhat
- Division of Pharmacology and Pharmaceutical Sciences, School of Pharmacy University of Missouri‐Kansas City Kansas City Missouri
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7
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Zaporozhchenko IA, Rykova EY, Laktionov PP. The Fundamentals of miRNA Biology: Structure, Biogenesis, and Regulatory Functions. RUSSIAN JOURNAL OF BIOORGANIC CHEMISTRY 2020. [DOI: 10.1134/s106816202001015x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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8
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Abstract
The biological functions of RNA range from gene regulation through catalysis and depend critically on its structure and flexibility. Conformational variations of flexible, non-base-paired components, including RNA hinges, bulges, or single-stranded tails, are well documented. Recent work has also identified variations in the structure of ubiquitous, base-paired duplexes found in almost all functional RNAs. Duplexes anchor the structures of folded RNAs, and their surface features are recognized by partner molecules. To date, no consistent picture has been obtained that describes the range of conformations assumed by RNA duplexes. Here, we apply wide angle, solution X-ray scattering (WAXS) to quantify these variations, by sampling length scales characteristic of helical geometries under different solution conditions. To identify the radius, helical rise, twist, and length of dsRNA helices, we exploit molecular dynamics generated structures, explicit solvent models, and ensemble optimization methods. Our results quantify the substantial and salt-dependent deviations of double-stranded (ds) RNA duplexes from the assumed canonical A-form conformation. Recent experiments underscore the need to properly describe the structures of RNA duplexes when interpreting the salt dependence of RNA conformations.
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Affiliation(s)
- Yen-Lin Chen
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853
| | - Lois Pollack
- School of Applied and Engineering Physics, Cornell University, Ithaca, NY 14853
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9
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Stavast CJ, Erkeland SJ. The Non-Canonical Aspects of MicroRNAs: Many Roads to Gene Regulation. Cells 2019; 8:cells8111465. [PMID: 31752361 PMCID: PMC6912820 DOI: 10.3390/cells8111465] [Citation(s) in RCA: 191] [Impact Index Per Article: 38.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 11/14/2019] [Accepted: 11/16/2019] [Indexed: 12/13/2022] Open
Abstract
MicroRNAs (miRNAs) are critical regulators of gene expression. As miRNAs are frequently deregulated in many human diseases, including cancer and immunological disorders, it is important to understand their biological functions. Typically, miRNA-encoding genes are transcribed by RNA Polymerase II and generate primary transcripts that are processed by RNase III-endonucleases DROSHA and DICER into small RNAs of approximately 21 nucleotides. All miRNAs are loaded into Argonaute proteins in the RNA-induced silencing complex (RISC) and act as post-transcriptional regulators by binding to the 3'- untranslated region (UTR) of mRNAs. This seed-dependent miRNA binding inhibits the translation and/or promotes the degradation of mRNA targets. Surprisingly, recent data presents evidence for a target-mediated decay mechanism that controls the level of specific miRNAs. In addition, several non-canonical miRNA-containing genes have been recently described and unexpected functions of miRNAs have been identified. For instance, several miRNAs are located in the nucleus, where they are involved in the transcriptional activation or silencing of target genes. These epigenetic modifiers are recruited by RISC and guided by miRNAs to specific loci in the genome. Here, we will review non-canonical aspects of miRNA biology, including novel regulators of miRNA expression and functions of miRNAs in the nucleus.
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10
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Loh HY, Norman BP, Lai KS, Rahman NMANA, Alitheen NBM, Osman MA. The Regulatory Role of MicroRNAs in Breast Cancer. Int J Mol Sci 2019; 20:E4940. [PMID: 31590453 PMCID: PMC6801796 DOI: 10.3390/ijms20194940] [Citation(s) in RCA: 187] [Impact Index Per Article: 37.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 08/21/2019] [Accepted: 08/23/2019] [Indexed: 02/06/2023] Open
Abstract
MicroRNAs (miRNAs) are small non-coding RNA molecules which function as critical post-transcriptional gene regulators of various biological functions. Generally, miRNAs negatively regulate gene expression by binding to their selective messenger RNAs (mRNAs), thereby leading to either mRNA degradation or translational repression, depending on the degree of complementarity with target mRNA sequences. Aberrant expression of these miRNAs has been linked etiologically with various human diseases including breast cancer. Different cellular pathways of breast cancer development such as cell proliferation, apoptotic response, metastasis, cancer recurrence and chemoresistance are regulated by either the oncogenic miRNA (oncomiR) or tumor suppressor miRNA (tsmiR). In this review, we highlight the current state of research into miRNA involved in breast cancer, with particular attention to articles published between the years 2000 to 2019, using detailed searches of the databases PubMed, Google Scholar, and Scopus. The post-transcriptional gene regulatory roles of various dysregulated miRNAs in breast cancer and their potential as therapeutic targets are also discussed.
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Affiliation(s)
- Hui-Yi Loh
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia.
| | - Brendan P Norman
- Department of Musculoskeletal Biology, Institute of Ageing and Chronic Disease, University of Liverpool, Liverpool L7 8TX, UK.
| | - Kok-Song Lai
- Health Sciences Division, Abu Dhabi Women's College, Higher Colleges of Technology, Abu Dhabi 41012, UAE.
| | - Nik Mohd Afizan Nik Abd Rahman
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia.
| | - Noorjahan Banu Mohamed Alitheen
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia.
| | - Mohd Azuraidi Osman
- Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang, Selangor 43400, Malaysia.
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11
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Deng L, Ren R, Liu Z, Song M, Li J, Wu Z, Ren X, Fu L, Li W, Zhang W, Guillen P, Izpisua Belmonte JC, Chan P, Qu J, Liu GH. Stabilizing heterochromatin by DGCR8 alleviates senescence and osteoarthritis. Nat Commun 2019; 10:3329. [PMID: 31350386 PMCID: PMC6659673 DOI: 10.1038/s41467-019-10831-8] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 06/03/2019] [Indexed: 01/01/2023] Open
Abstract
DiGeorge syndrome critical region 8 (DGCR8) is a critical component of the canonical microprocessor complex for microRNA biogenesis. However, the non-canonical functions of DGCR8 have not been studied. Here, we demonstrate that DGCR8 plays an important role in maintaining heterochromatin organization and attenuating aging. An N-terminal-truncated version of DGCR8 (DR8dex2) accelerated senescence in human mesenchymal stem cells (hMSCs) independent of its microRNA-processing activity. Further studies revealed that DGCR8 maintained heterochromatin organization by interacting with the nuclear envelope protein Lamin B1, and heterochromatin-associated proteins, KAP1 and HP1γ. Overexpression of any of these proteins, including DGCR8, reversed premature senescent phenotypes in DR8dex2 hMSCs. Finally, DGCR8 was downregulated in pathologically and naturally aged hMSCs, whereas DGCR8 overexpression alleviated hMSC aging and mouse osteoarthritis. Taken together, these analyses uncovered a novel, microRNA processing-independent role in maintaining heterochromatin organization and attenuating senescence by DGCR8, thus representing a new therapeutic target for alleviating human aging-related disorders.
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Affiliation(s)
- Liping Deng
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Ruotong Ren
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China
| | - Zunpeng Liu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Moshi Song
- State Key Laboratory of Membrane Biology, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, 100101, Beijing, China
| | - Jingyi Li
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China
- Advanced Innovation Center for Human Brain Protection, National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, 100053, Beijing, China
| | - Zeming Wu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Xiaoqing Ren
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Lina Fu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
| | - Wei Li
- Advanced Innovation Center for Human Brain Protection, National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, 100053, Beijing, China
| | - Weiqi Zhang
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China
- University of Chinese Academy of Sciences, 100049, Beijing, China
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, 100101, Beijing, China
- Advanced Innovation Center for Human Brain Protection, National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, 100053, Beijing, China
- Key Laboratory of Genomics and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, 100101, Beijing, China
| | - Pedro Guillen
- Clinica Cemtro. Av. del Ventisquero de la Condesa, 42, 28035, Madrid, Spain
| | | | - Piu Chan
- Advanced Innovation Center for Human Brain Protection, National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, 100053, Beijing, China
| | - Jing Qu
- State Key Laboratory of Stem Cell and Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 100101, Beijing, China.
- University of Chinese Academy of Sciences, 100049, Beijing, China.
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, 100101, Beijing, China.
| | - Guang-Hui Liu
- National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 100101, Beijing, China.
- University of Chinese Academy of Sciences, 100049, Beijing, China.
- Institute for Stem Cell and Regeneration, Chinese Academy of Sciences, 100101, Beijing, China.
- Advanced Innovation Center for Human Brain Protection, National Clinical Research Center for Geriatric Disorders, Xuanwu Hospital Capital Medical University, 100053, Beijing, China.
- Key Laboratory of Regenerative Medicine of Ministry of Education, Institute of Aging and Regenerative Medicine, Jinan University, 510632, Guangzhou, China.
- Beijing Institute for Brain Disorders, Capital Medical University, 100069, Beijing, China.
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12
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Nguyen HM, Nguyen TD, Nguyen TL, Nguyen TA. Orientation of Human Microprocessor on Primary MicroRNAs. Biochemistry 2018; 58:189-198. [DOI: 10.1021/acs.biochem.8b00944] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Huong Minh Nguyen
- Laboratory of Molecular Microbiology, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam
| | - Trung Duc Nguyen
- Division of Life Science, Hong Kong University of Science & Technology, Hong Kong, China
| | - Thuy Linh Nguyen
- Division of Life Science, Hong Kong University of Science & Technology, Hong Kong, China
| | - Tuan Anh Nguyen
- Division of Life Science, Hong Kong University of Science & Technology, Hong Kong, China
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13
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Creugny A, Fender A, Pfeffer S. Regulation of primary microRNA processing. FEBS Lett 2018; 592:1980-1996. [PMID: 29683487 DOI: 10.1002/1873-3468.13067] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 04/12/2018] [Accepted: 04/16/2018] [Indexed: 12/28/2022]
Abstract
MicroRNAs (miRNAs) are evolutionarily conserved small regulatory RNAs that participate in the adjustment of many, if not all, fundamental biological processes. Molecular mechanisms involved in miRNA biogenesis and mode of action have been elucidated in the past two decades. Similar to many cellular pathways, miRNA processing and function can be globally or specifically regulated at several levels and by numerous proteins and RNAs. Given their role as fine-tuning molecules, it is essential for miRNA expression to be tightly regulated in order to maintain cellular homeostasis. Here, we review our current knowledge of the first step of their maturation occurring in the nucleus and how it can be specifically and dynamically modulated.
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Affiliation(s)
- Antoine Creugny
- Architecture and Reactivity of RNA, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, France
| | - Aurélie Fender
- Architecture and Reactivity of RNA, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, France
| | - Sébastien Pfeffer
- Architecture and Reactivity of RNA, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, France
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14
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Heller D, Krestel R, Ohler U, Vingron M, Marsico A. ssHMM: extracting intuitive sequence-structure motifs from high-throughput RNA-binding protein data. Nucleic Acids Res 2017; 45:11004-11018. [PMID: 28977546 PMCID: PMC5737366 DOI: 10.1093/nar/gkx756] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2016] [Accepted: 08/17/2017] [Indexed: 11/14/2022] Open
Abstract
RNA-binding proteins (RBPs) play an important role in RNA post-transcriptional regulation and recognize target RNAs via sequence-structure motifs. The extent to which RNA structure influences protein binding in the presence or absence of a sequence motif is still poorly understood. Existing RNA motif finders either take the structure of the RNA only partially into account, or employ models which are not directly interpretable as sequence-structure motifs. We developed ssHMM, an RNA motif finder based on a hidden Markov model (HMM) and Gibbs sampling which fully captures the relationship between RNA sequence and secondary structure preference of a given RBP. Compared to previous methods which output separate logos for sequence and structure, it directly produces a combined sequence-structure motif when trained on a large set of sequences. ssHMM's model is visualized intuitively as a graph and facilitates biological interpretation. ssHMM can be used to find novel bona fide sequence-structure motifs of uncharacterized RBPs, such as the one presented here for the YY1 protein. ssHMM reaches a high motif recovery rate on synthetic data, it recovers known RBP motifs from CLIP-Seq data, and scales linearly on the input size, being considerably faster than MEMERIS and RNAcontext on large datasets while being on par with GraphProt. It is freely available on Github and as a Docker image.
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Affiliation(s)
- David Heller
- Max Planck Institute for Molecular Genetics, Ihnestr. 63-73 14195 Berlin, Germany.,Hasso Plattner Institute, Prof.-Dr.-Helmert-Str. 2-3 14482 Potsdam, Germany
| | - Ralf Krestel
- Hasso Plattner Institute, Prof.-Dr.-Helmert-Str. 2-3 14482 Potsdam, Germany
| | - Uwe Ohler
- Max Delbruck Center, Robert-Roessle-Str. 10 13029 Berlin, Germany
| | - Martin Vingron
- Max Planck Institute for Molecular Genetics, Ihnestr. 63-73 14195 Berlin, Germany
| | - Annalisa Marsico
- Max Planck Institute for Molecular Genetics, Ihnestr. 63-73 14195 Berlin, Germany.,Freie Universitaet Berlin, Arnimallee 14 14195 Berlin, Germany
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15
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The insertion in the double-stranded RNA binding domain of human Drosha is important for its function. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1860:1179-1188. [PMID: 29109067 DOI: 10.1016/j.bbagrm.2017.10.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2017] [Revised: 10/30/2017] [Accepted: 10/31/2017] [Indexed: 12/20/2022]
Abstract
microRNAs (miRNAs) are first transcribed as long, primary transcripts, which are then processed by multiple enzymes and proteins to generate the single-stranded, approximately 22-nucleotide (nt)-long mature miRNAs. A critical step in animal miRNA biogenesis is the cleavage of primary miRNA transcripts (pri-miRNAs) to produce precursor miRNAs (pre-miRNAs) by the enzyme Drosha. How Drosha recognizes its substrates remains incompletely understood. In this study we constructed a series of human Drosha mutants and examined their enzymatic activities and interaction with RNAs. We found that the N-terminal region is required for the nuclear localization and cellular function of Drosha. And in contrast to previous reports, we showed that the double-stranded RNA binding domain (RBD) of Drosha exhibited a weak but noticeable affinity for RNA. Compared to the RBDs of other RNA-binding proteins, the RBD of Drosha has a short insert, whose mutations reduced RNA binding and pri-miRNA cleavage. Overexpression of Drosha RBD mutants in a reporter assay corroborated their deficiencies in Drosha activity in cell cultures. In addition, we found that point mutations in the RNaseIIIb domain of Drosha implicated in Wilms tumors differentially affected cleavage of the 5' and 3' strands of pri-miRNAs in vitro. In conclusion, our results provided important insights into the mechanism of pri-miRNA processing by human Drosha.
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16
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Kranick JC, Chadalavada DM, Sahu D, Showalter SA. Engineering double-stranded RNA binding activity into the Drosha double-stranded RNA binding domain results in a loss of microRNA processing function. PLoS One 2017; 12:e0182445. [PMID: 28792523 PMCID: PMC5549741 DOI: 10.1371/journal.pone.0182445] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Accepted: 07/18/2017] [Indexed: 11/19/2022] Open
Abstract
Canonical processing of miRNA begins in the nucleus with the Microprocessor complex, which is minimally composed of the RNase III enzyme Drosha and two copies of its cofactor protein DGCR8. In structural analogy to most RNase III enzymes, Drosha possesses a modular domain with the double-stranded RNA binding domain (dsRBD) fold. Unlike the dsRBDs found in most members of the RNase III family, the Drosha-dsRBD does not display double-stranded RNA binding activity; perhaps related to this, the Drosha-dsRBD amino acid sequence does not conform well to the canonical patterns expected for a dsRBD. In this article, we investigate the impact on miRNA processing of engineering double-stranded RNA binding activity into Drosha's non-canonical dsRBD. Our findings corroborate previous studies that have demonstrated the Drosha-dsRBD is necessary for miRNA processing and suggest that the amino acid composition in the second α-helix of the domain is critical to support its evolved function.
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Affiliation(s)
- Joshua C. Kranick
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Durga M. Chadalavada
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Debashish Sahu
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Scott A. Showalter
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
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17
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Acevedo R, Evans D, Penrod KA, Showalter SA. Binding by TRBP-dsRBD2 Does Not Induce Bending of Double-Stranded RNA. Biophys J 2017; 110:2610-2617. [PMID: 27332119 DOI: 10.1016/j.bpj.2016.05.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 04/20/2016] [Accepted: 05/09/2016] [Indexed: 12/23/2022] Open
Abstract
Protein-nucleic acid interactions are central to a variety of biological processes, many of which involve large-scale conformational changes that lead to bending of the nucleic acid helix. Here, we focus on the nonsequence-specific protein TRBP, whose double-stranded RNA-binding domains (dsRBDs) interact with the A-form geometry of double-stranded RNA (dsRNA). Crystal structures of dsRBD-dsRNA interactions suggest that the dsRNA helix must bend in such a way that its major groove expands to conform to the dsRBD's binding surface. We show through isothermal titration calorimetry experiments that dsRBD2 of TRBP binds dsRNA with a temperature-independent observed binding affinity (KD ∼500 nM). Furthermore, a near-zero observed heat capacity change (ΔCp = 70 ± 40 cal·mol(-1)·K(-1)) suggests that large-scale conformational changes do not occur upon binding. This result is bolstered by molecular-dynamics simulations in which dsRBD-dsRNA interactions generate only modest bending of the RNA along its helical axis. Overall, these results suggest that this particular dsRBD-dsRNA interaction produces little to no change in the A-form geometry of dsRNA in solution. These results further support our previous hypothesis, based on extensive gel-shift assays, that TRBP preferentially binds to sites of nearly ideal A-form structure while being excluded from sites of local deformation in the RNA helical structure. The implications of this mechanism for efficient micro-RNA processing will be discussed.
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Affiliation(s)
- Roderico Acevedo
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania; Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania
| | - Declan Evans
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania; Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania
| | - Katheryn A Penrod
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania; Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania
| | - Scott A Showalter
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania; Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania; Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania.
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18
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Zhang N, Ashizawa T. RNA toxicity and foci formation in microsatellite expansion diseases. Curr Opin Genet Dev 2017; 44:17-29. [PMID: 28208060 DOI: 10.1016/j.gde.2017.01.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Revised: 01/04/2017] [Accepted: 01/18/2017] [Indexed: 12/11/2022]
Abstract
More than 30 incurable neurological and neuromuscular diseases are caused by simple microsatellite expansions consisted of 3-6 nucleotides. These repeats can occur in non-coding regions and often result in a dominantly inherited disease phenotype that is characteristic of a toxic RNA gain-of-function. The expanded RNA adopts unusual secondary structures, sequesters various RNA binding proteins to form insoluble nuclear foci, and causes cellular defects at a multisystem level. Nuclear foci are dynamic in size, shape and colocalization of RNA binding proteins in different expansion diseases and tissue types. This review sets to provide new insights into the disease mechanisms of RNA toxicity and foci modulation, in light of recent advancement on bi-directional transcription, antisense RNA, repeat-associated non-ATG translation and beyond.
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Affiliation(s)
- Nan Zhang
- Neurosciences Research Program, Houston Methodist Research Institute, Houston, TX 77030, United States; Division of Cell and Molecular Biology, South Kensington Campus, Imperial College London, London SW7 2AZ, UK
| | - Tetsuo Ashizawa
- Neurosciences Research Program, Houston Methodist Research Institute, Houston, TX 77030, United States.
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19
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Yang L, Yan Z, Wang Y, Ma W, Li C. Down-expression of miR-154 suppresses tumourigenesis in CD133+glioblastoma stem cells. Cell Biochem Funct 2016; 34:404-13. [PMID: 27338789 DOI: 10.1002/cbf.3201] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 05/16/2016] [Accepted: 06/01/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Liang Yang
- Department of Neurosurgery; The Second Hospital of Hebei Medical University; Shijiazhuang China
| | - Zhongjie Yan
- Department of Neurosurgery; The Second Hospital of Hebei Medical University; Shijiazhuang China
| | - Yuanyu Wang
- Department of Neurosurgery; The Second Hospital of Hebei Medical University; Shijiazhuang China
| | - Wandong Ma
- Department of Neurosurgery; The Second Hospital of Hebei Medical University; Shijiazhuang China
| | - Chen Li
- Department of Neurosurgery; The Second Hospital of Hebei Medical University; Shijiazhuang China
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20
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Yang WY, Gao R, Southern M, Sarkar PS, Disney MD. Design of a bioactive small molecule that targets r(AUUCU) repeats in spinocerebellar ataxia 10. Nat Commun 2016; 7:11647. [PMID: 27248057 PMCID: PMC4895354 DOI: 10.1038/ncomms11647] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Accepted: 04/18/2016] [Indexed: 12/22/2022] Open
Abstract
RNA is an important target for chemical probes of function and lead therapeutics; however, it is difficult to target with small molecules. One approach to tackle this problem is to identify compounds that target RNA structures and utilize them to multivalently target RNA. Here we show that small molecules can be identified to selectively bind RNA base pairs by probing a library of RNA-focused small molecules. A small molecule that selectively binds AU base pairs informed design of a dimeric compound (2AU-2) that targets the pathogenic RNA, expanded r(AUUCU) repeats, that causes spinocerebellar ataxia type 10 (SCA10) in patient-derived cells. Indeed, 2AU-2 (50 nM) ameliorates various aspects of SCA10 pathology including improvement of mitochondrial dysfunction, reduced activation of caspase 3, and reduction of nuclear foci. These studies provide a first-in-class chemical probe to study SCA10 RNA toxicity and potentially define broadly applicable compounds targeting RNA AU base pairs in cells. Expanded RNA repeats in non-coding region of a gene represent a hallmark of several diseases. Here, the authors identify two small molecules that selectively bind AU repeats and use them to design a compound that targets the pathogenic RNA associated with spinocerebellar ataxia type 10.
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Affiliation(s)
- Wang-Yong Yang
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458, USA
| | - Rui Gao
- Mitchell Center for Neurodegenerative Disorders, Department of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, USA
| | - Mark Southern
- Informatics Core, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458, USA
| | - Partha S Sarkar
- Mitchell Center for Neurodegenerative Disorders, Department of Neurology, Neuroscience and Cell Biology, University of Texas Medical Branch, Galveston, Texas 77555, USA
| | - Matthew D Disney
- Departments of Chemistry and Neuroscience, The Scripps Research Institute, Scripps Florida, Jupiter, Florida 33458, USA
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21
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Herbert KM, Sarkar SK, Mills M, Delgado De la Herran HC, Neuman KC, Steitz JA. A heterotrimer model of the complete Microprocessor complex revealed by single-molecule subunit counting. RNA (NEW YORK, N.Y.) 2016; 22:175-183. [PMID: 26683315 PMCID: PMC4712668 DOI: 10.1261/rna.054684.115] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Accepted: 11/17/2015] [Indexed: 05/30/2023]
Abstract
During microRNA (miRNA) biogenesis, the Microprocessor complex (MC), composed minimally of Drosha, an RNaseIII enzyme, and DGCR8, a double-stranded RNA-binding protein, cleaves the primary-miRNA (pri-miRNA) to release the pre-miRNA stem-loop structure. Size-exclusion chromatography of the MC, isolated from mammalian cells, suggested multiple copies of one or both proteins in the complex. However, the exact stoichiometry was unknown. Initial experiments suggested that DGCR8 bound pri-miRNA substrates specifically, and given that Drosha could not be bound or cross-linked to RNA, a sequential model for binding was established in which DGCR8 bound first and recruited Drosha. Therefore, many laboratories have studied DGCR8 binding to RNA in the absence of Drosha and have shown that deletion constructs of DGCR8 can multimerize in the presence of RNA. More recently, it was demonstrated that Drosha can bind pri-miRNA substrates in the absence of DGCR8, casting doubt on the sequential model of binding. In the same study, using a single-molecule photobleaching assay, fluorescent protein-tagged deletion constructs of DGCR8 and Drosha assembled into a heterotrimeric complex on RNA, comprising two DGCR8 molecules and one Drosha molecule. To determine the stoichiometry of Drosha and DGCR8 within the MC in the absence of added RNA, we also used a single-molecule photobleaching assay and confirmed the heterotrimeric model of the human MC. We demonstrate that a heterotrimeric complex is likely preformed in the absence of RNA and exists even when full-length proteins are expressed and purified from human cells, and when hAGT-derived tags are used rather than fluorescent proteins.
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Affiliation(s)
- Kristina M Herbert
- Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06536, USA Department of Microbiology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California 22860, Mexico
| | - Susanta K Sarkar
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Maria Mills
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Hilda C Delgado De la Herran
- Department of Microbiology, Center for Scientific Research and Higher Education of Ensenada (CICESE), Ensenada, Baja California 22860, Mexico
| | - Keir C Neuman
- Laboratory of Molecular Biophysics, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Joan A Steitz
- Department of Molecular Biophysics and Biochemistry, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, Connecticut 06536, USA
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22
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Kwon SC, Nguyen TA, Choi YG, Jo MH, Hohng S, Kim VN, Woo JS. Structure of Human DROSHA. Cell 2015; 164:81-90. [PMID: 26748718 DOI: 10.1016/j.cell.2015.12.019] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 11/28/2015] [Accepted: 12/07/2015] [Indexed: 01/29/2023]
Abstract
MicroRNA maturation is initiated by RNase III DROSHA that cleaves the stem loop of primary microRNA. DROSHA functions together with its cofactor DGCR8 in a heterotrimeric complex known as Microprocessor. Here, we report the X-ray structure of DROSHA in complex with the C-terminal helix of DGCR8. We find that DROSHA contains two DGCR8-binding sites, one on each RNase III domain (RIIID), which mediate the assembly of Microprocessor. The overall structure of DROSHA is surprisingly similar to that of Dicer despite no sequence homology apart from the C-terminal part, suggesting that DROSHA may have evolved from a Dicer homolog. DROSHA exhibits unique features, including non-canonical zinc-finger motifs, a long insertion in the first RIIID, and the kinked link between Connector helix and RIIID, which explains the 11-bp-measuring "ruler" activity of DROSHA. Our study implicates the evolutionary origin of DROSHA and elucidates the molecular basis of Microprocessor assembly and primary microRNA processing.
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Affiliation(s)
- S Chul Kwon
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Tuan Anh Nguyen
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Yeon-Gil Choi
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea
| | - Myung Hyun Jo
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea; National Center for Creative Research Initiatives, Seoul National University, Seoul 08826, Korea; Institute of Applied Physics, Seoul National University, Seoul 08826, Korea
| | - Sungchul Hohng
- Department of Physics and Astronomy, Seoul National University, Seoul 08826, Korea; National Center for Creative Research Initiatives, Seoul National University, Seoul 08826, Korea; Institute of Applied Physics, Seoul National University, Seoul 08826, Korea; Department of Biophysics and Chemical Biology, Seoul National University, Seoul 08826, Korea
| | - V Narry Kim
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea.
| | - Jae-Sung Woo
- Center for RNA Research, Institute for Basic Science, Seoul 08826, Korea; School of Biological Sciences, Seoul National University, Seoul 08826, Korea.
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23
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Macias S, Cordiner RA, Gautier P, Plass M, Cáceres JF. DGCR8 Acts as an Adaptor for the Exosome Complex to Degrade Double-Stranded Structured RNAs. Mol Cell 2015; 60:873-85. [PMID: 26687677 PMCID: PMC4691244 DOI: 10.1016/j.molcel.2015.11.011] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 07/16/2015] [Accepted: 11/06/2015] [Indexed: 01/18/2023]
Abstract
The Microprocessor complex (DGCR8/Drosha) is required for microRNA (miRNA) biogenesis but also binds and regulates the stability of several types of cellular RNAs. Of particular interest, DGCR8 controls the stability of mature small nucleolar RNA (snoRNA) transcripts independently of Drosha, suggesting the existence of alternative DGCR8 complex(es) with other nucleases to process a variety of cellular RNAs. Here, we found that DGCR8 copurifies with subunits of the nuclear exosome, preferentially associating with its hRRP6-containing nucleolar form. Importantly, we demonstrate that DGCR8 is essential for the recruitment of the exosome to snoRNAs and to human telomerase RNA. In addition, we show that the DGCR8/exosome complex controls the stability of the human telomerase RNA component (hTR/TERC). Altogether, these data suggest that DGCR8 acts as an adaptor to recruit the exosome complex to structured RNAs and induce their degradation. DGCR8 forms an alternative complex with the hRRP6-containing form of the exosome DGCR8 acts as an adaptor to recruit the exosome to target structured RNAs The DGCR8/hRRP6 complex also controls the stability of human telomerase RNA
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Affiliation(s)
- Sara Macias
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Ross A Cordiner
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Philippe Gautier
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK
| | - Mireya Plass
- Department of Biology, Center for Computational and Applied Transcriptomics, University of Copenhagen, Ole Maaloes Vej 5, 2200 Copenhagen, Denmark
| | - Javier F Cáceres
- Medical Research Council Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Western General Hospital, Edinburgh EH4 2XU, UK.
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24
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Kebschull M, Papapanou PN. Mini but mighty: microRNAs in the pathobiology of periodontal disease. Periodontol 2000 2015; 69:201-20. [PMID: 26252410 PMCID: PMC4530521 DOI: 10.1111/prd.12095] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/03/2015] [Indexed: 12/19/2022]
Abstract
MicroRNAs (miRNAs) are a family of small, noncoding RNA molecules that negatively regulate protein expression either by inhibiting initiation of the translation of mRNA or by inducing the degradation of mRNA molecules. Accumulating evidence suggests that miRNA-mediated repression of protein expression is of paramount importance in a broad range of physiologic and pathologic conditions. In particular, miRNA-induced dysregulation of molecular processes involved in inflammatory pathways has been shown to contribute to the development of chronic inflammatory diseases. In this review, first of all we provide an overview of miRNA biogenesis, the main mechanisms of action and the miRNA profiling tools currently available. Then, we summarize the available evidence supporting a specific role for miRNAs in the pathobiology of periodontitis. Based on a review of available data on the differential expression of miRNAs in gingival tissues in states of periodontal health and disease, we address specific roles for miRNAs in molecular and cellular pathways causally linked to periodontitis. Our review points to several lines of evidence suggesting the involvement of miRNAs in periodontal tissue homeostasis and pathology. Although the intricate regulatory networks affected by miRNA function are still incompletely mapped, further utilization of systems biology tools is expected to enhance our understanding of the pathobiology of periodontitis.
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Affiliation(s)
- Moritz Kebschull
- Associate Professor of Dental Medicine, Consultant, Department of Periodontology, Operative and Preventive Dentistry, University of Bonn, Welschnonnenstr. 17, 53111 Bonn, Germany, Tel: +49-228-28722-007,
| | - Panos N. Papapanou
- Professor of Dental Medicine, Director, Division of Periodontics, Chair, Section of Oral and Diagnostic Sciences, Columbia University College of Dental Medicine, 630 West 168 Street, PH-7E-110, New York, NY 10032, USA, Tel: +1-212-342-3008, Fax: +1-212-305-9313,
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25
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Tu CC, Zhong Y, Nguyen L, Tsai A, Sridevi P, Tarn WY, Wang JYJ. The kinase ABL phosphorylates the microprocessor subunit DGCR8 to stimulate primary microRNA processing in response to DNA damage. Sci Signal 2015; 8:ra64. [PMID: 26126715 DOI: 10.1126/scisignal.aaa4468] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The DNA damage response network stimulates microRNA (miRNA) biogenesis to coordinate repair, cell cycle checkpoints, and apoptosis. The multistep process of miRNA biogenesis involves the cleavage of primary miRNAs by the microprocessor complex composed of the ribonuclease Drosha and the RNA binding protein DGCR8. We found that the tyrosine kinase ABL phosphorylated DGCR8, a modification that was required for the induction of a subset of miRNAs after DNA damage. Focusing on the miR-34 family, ABL stimulated the production of miR-34c, but not miR-34a, through Drosha/DGCR8-dependent processing of primary miR-34c (pri-miR-34c). This miRNA-selective effect of ABL required the sequences flanking the precursor miR-34c (pre-miR-34c) stem-loop. In pri-miRNA processing, DGCR8 binds the pre-miR stem-loop and recruits Drosha to the miRNA. RNA cross-linking assays showed that DGCR8 and Drosha interacted with pri-miR-34c, but we found an inverse correlation between ABL-stimulated processing and DGCR8 association with pri-miR-34c. When coexpressed in HEK293T cells, ABL phosphorylated DGCR8 at Tyr(267). Ectopic expression of a Y267F-DGCR8 mutant reduced the recruitment of Drosha to pri-miR-34c and prevented ABL or Drosha from stimulating the processing of pri-miR-34c. In mice engineered to express a nuclear import-defective mutant of ABL, miR-34c, but not miR-34a, expression was reduced in the kidney, and apoptosis of the renal epithelial cells was impaired in response to cisplatin. These results reveal a new pathway in the DNA damage response wherein ABL-dependent tyrosine phosphorylation of DGCR8 stimulates the processing of selective primary miRNAs.
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Affiliation(s)
- Chi-Chiang Tu
- Moores Cancer Center and Division of Hematology-Oncology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0644, USA. Institute of Biomedical Sciences, Academia Sinica, Taipei 11529 Taiwan
| | - Yan Zhong
- Moores Cancer Center and Division of Hematology-Oncology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0644, USA
| | - Louis Nguyen
- Moores Cancer Center and Division of Hematology-Oncology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0644, USA
| | - Aaron Tsai
- Moores Cancer Center and Division of Hematology-Oncology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0644, USA
| | - Priya Sridevi
- Moores Cancer Center and Division of Hematology-Oncology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0644, USA
| | - Woan-Yuh Tarn
- Institute of Biomedical Sciences, Academia Sinica, Taipei 11529 Taiwan
| | - Jean Y J Wang
- Moores Cancer Center and Division of Hematology-Oncology, Department of Medicine, University of California, San Diego, La Jolla, CA 92093-0644, USA.
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26
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Functional Anatomy of the Human Microprocessor. Cell 2015; 161:1374-87. [PMID: 26027739 DOI: 10.1016/j.cell.2015.05.010] [Citation(s) in RCA: 260] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 03/06/2015] [Accepted: 03/24/2015] [Indexed: 01/26/2023]
Abstract
MicroRNA (miRNA) maturation is initiated by Microprocessor composed of RNase III DROSHA and its cofactor DGCR8, whose fidelity is critical for generation of functional miRNAs. To understand how Microprocessor recognizes pri-miRNAs, we here reconstitute human Microprocessor with purified recombinant proteins. We find that Microprocessor is an ∼364 kDa heterotrimeric complex of one DROSHA and two DGCR8 molecules. Together with a 23-amino acid peptide from DGCR8, DROSHA constitutes a minimal functional core. DROSHA serves as a "ruler" by measuring 11 bp from the basal ssRNA-dsRNA junction. DGCR8 interacts with the stem and apical elements through its dsRNA-binding domains and RNA-binding heme domain, respectively, allowing efficient and accurate processing. DROSHA and DGCR8, respectively, recognize the basal UG and apical UGU motifs, which ensure proper orientation of the complex. These findings clarify controversies over the action mechanism of DROSHA and allow us to build a general model for pri-miRNA processing.
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Quarles KA, Chadalavada D, Showalter SA. Deformability in the cleavage site of primary microRNA is not sensed by the double-stranded RNA binding domains in the microprocessor component DGCR8. Proteins 2015; 83:1165-79. [PMID: 25851436 DOI: 10.1002/prot.24810] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 03/10/2015] [Accepted: 03/25/2015] [Indexed: 01/01/2023]
Abstract
The prevalence of double-stranded RNA (dsRNA) in eukaryotic cells has only recently been appreciated. Of interest here, RNA silencing begins with dsRNA substrates that are bound by the dsRNA-binding domains (dsRBDs) of their processing proteins. Specifically, processing of microRNA (miRNA) in the nucleus minimally requires the enzyme Drosha and its dsRBD-containing cofactor protein, DGCR8. The smallest recombinant construct of DGCR8 that is sufficient for in vitro dsRNA binding, referred to as DGCR8-Core, consists of its two dsRBDs and a C-terminal tail. As dsRBDs rarely recognize the nucleotide sequence of dsRNA, it is reasonable to hypothesize that DGCR8 function is dependent on the recognition of specific structural features in the miRNA precursor. Previously, we demonstrated that noncanonical structural elements that promote RNA flexibility within the stem of miRNA precursors are necessary for efficient in vitro cleavage by reconstituted Microprocessor complexes. Here, we combine gel shift assays with in vitro processing assays to demonstrate that neither the N-terminal dsRBD of DGCR8 in isolation nor the DGCR8-Core construct is sensitive to the presence of noncanonical structural elements within the stem of miRNA precursors, or to single-stranded segments flanking the stem. Extending DGCR8-Core to include an N-terminal heme-binding region does not change our conclusions. Thus, our data suggest that although the DGCR8-Core region is necessary for dsRNA binding and recruitment to the Microprocessor, it is not sufficient to establish the previously observed connection between RNA flexibility and processing efficiency.
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Affiliation(s)
- Kaycee A Quarles
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvannia, 16802
| | - Durga Chadalavada
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvannia, 16802
| | - Scott A Showalter
- Department of Chemistry, Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvannia, 16802
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Acevedo R, Orench-Rivera N, Quarles KA, Showalter SA. Helical defects in microRNA influence protein binding by TAR RNA binding protein. PLoS One 2015; 10:e0116749. [PMID: 25608000 PMCID: PMC4301919 DOI: 10.1371/journal.pone.0116749] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Accepted: 12/12/2014] [Indexed: 01/19/2023] Open
Abstract
Background MicroRNAs (miRNAs) are critical post-transcriptional regulators of gene expression. Their precursors have a globally A-form helical geometry, which prevents most proteins from identifying their nucleotide sequence. This suggests the hypothesis that local structural features (e.g., bulges, internal loops) play a central role in specific double-stranded RNA (dsRNA) selection from cellular RNA pools by dsRNA binding domain (dsRBD) containing proteins. Furthermore, the processing enzymes in the miRNA maturation pathway require tandem-dsRBD cofactor proteins for optimal function, suggesting that dsRBDs play a key role in the molecular mechanism for precise positioning of the RNA within these multi-protein complexes. Here, we focus on the tandem-dsRBDs of TRBP, which have been shown to bind dsRNA tightly. Methodology/Principal Findings We present a combination of dsRNA binding assays demonstrating that TRBP binds dsRNA in an RNA-length dependent manner. Moreover, circular dichroism data shows that the number of dsRBD moieties bound to RNA at saturation is different for a tandem-dsRBD construct than for constructs with only one dsRBD per polypeptide, revealing another reason for the selective pressure to maintain multiple domains within a polypeptide chain. Finally, we show that helical defects in precursor miRNA alter the apparent dsRNA size, demonstrating that imperfections in RNA structure influence the strength of TRBP binding. Conclusion/Significance We conclude that TRBP is responsible for recognizing structural imperfections in miRNA precursors, in the sense that TRBP is unable to bind imperfections efficiently and thus is positioned around them. We propose that once positioned around structural defects, TRBP assists Dicer and the rest of the RNA-induced silencing complex (RISC) in providing efficient and homogenous conversion of substrate precursor miRNA into mature miRNA downstream.
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Affiliation(s)
- Roderico Acevedo
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Nichole Orench-Rivera
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Kaycee A. Quarles
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
| | - Scott A. Showalter
- Department of Chemistry and Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania, United States of America
- * E-mail:
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Santulli G. A Fleeting Glimpse Inside microRNA, Epigenetics, and Micropeptidomics. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 887:1-14. [PMID: 26662983 PMCID: PMC4871246 DOI: 10.1007/978-3-319-22380-3_1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
MicroRNAs (miRs) are important regulators of gene expression in numerous biological processes. Their maturation process is herein described, including the most updated insights from the current literature. Circa 2000 miR sequences have been identified in the human genome, with over 50,000 miR-target interactions, including enzymes involved in epigenetic modulation of gene expression. Moreover, some "pieces of RNA" previously annotated as noncoding have been recently found to encode micropeptides that carry out critical mechanistic functions in the cell. Advanced techniques now available will certainly allow a precise scanning of the genome looking for micropeptides hidden within the "noncoding" RNA.
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Quick-Cleveland J, Jacob JP, Weitz SH, Shoffner G, Senturia R, Guo F. The DGCR8 RNA-binding heme domain recognizes primary microRNAs by clamping the hairpin. Cell Rep 2014; 7:1994-2005. [PMID: 24910438 DOI: 10.1016/j.celrep.2014.05.013] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Revised: 04/03/2014] [Accepted: 05/06/2014] [Indexed: 01/09/2023] Open
Abstract
Canonical primary microRNA transcripts (pri-miRNAs) are characterized by a ∼30 bp hairpin flanked by single-stranded regions. These pri-miRNAs are recognized and cleaved by the Microprocessor complex consisting of the Drosha nuclease and its obligate RNA-binding partner DGCR8. It is not well understood how the Microprocessor specifically recognizes pri-miRNA substrates. Here, we show that in addition to the well-known double-stranded RNA-binding domains, DGCR8 uses a dimeric heme-binding domain to directly contact pri-miRNAs. This RNA-binding heme domain (Rhed) directs two DGCR8 dimers to bind each pri-miRNA hairpin. The two Rhed-binding sites are located at both ends of the hairpin. The Rhed and its RNA-binding surface are important for pri-miRNA processing activity. Additionally, the heme cofactor is required for formation of processing-competent DGCR8-pri-miRNA complexes. Our study reveals a unique protein-RNA interaction central to pri-miRNA recognition. We propose a unifying model in which two DGCR8 dimers clamp a pri-miRNA hairpin using their Rheds.
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Affiliation(s)
- Jen Quick-Cleveland
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Jose P Jacob
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Sara H Weitz
- Molecular, Cell and Integrative Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Grant Shoffner
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Rachel Senturia
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Feng Guo
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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Santulli G, Iaccarino G, De Luca N, Trimarco B, Condorelli G. Atrial fibrillation and microRNAs. Front Physiol 2014; 5:15. [PMID: 24478726 PMCID: PMC3900852 DOI: 10.3389/fphys.2014.00015] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 01/08/2014] [Indexed: 12/17/2022] Open
Abstract
Atrial fibrillation (AF) is the most common sustained arrhythmia, especially in the elderly, and has a significant genetic component. Recently, several independent investigators have demonstrated a functional role for small non-coding RNAs (microRNAs) in the pathophysiology of this cardiac arrhythmia. This report represents a systematic and updated appraisal of the main studies that established a mechanistic association between specific microRNAs and AF, focusing both on the regulation of electrical and structural remodeling of cardiac tissue.
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Affiliation(s)
- Gaetano Santulli
- Department of Advanced Biomedical Sciences, "Federico II" University Hospital Naples, Italy ; Department of Translational Medical Sciences, "Federico II" University Hospital Naples, Italy ; Columbia University Medical Center, College of Physicians & Surgeons, New York Presbyterian Hospital - Manhattan New York, NY, USA
| | - Guido Iaccarino
- Department of Medicine and Surgery, University of Salerno Salerno, Italy ; IRCCS "Multimedica," Milano, Italy
| | - Nicola De Luca
- Department of Translational Medical Sciences, "Federico II" University Hospital Naples, Italy
| | - Bruno Trimarco
- Department of Advanced Biomedical Sciences, "Federico II" University Hospital Naples, Italy
| | - Gianluigi Condorelli
- Humanitas Clinical and Research Center Rozzano (Milan), Italy ; University of Milan Milan, Italy
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Xin C, Zhang H, Liu Z. miR-154 suppresses colorectal cancer cell growth and motility by targeting TLR2. Mol Cell Biochem 2013; 387:271-7. [PMID: 24242044 DOI: 10.1007/s11010-013-1892-3] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Accepted: 11/05/2013] [Indexed: 02/07/2023]
Abstract
MicroRNAs play critical roles in the development and progression of colorectal cancer (CRC). miR-154 acts as a tumor suppressor in several tumors; however, its role in CRC is poorly understood. Herein, we found that miR-154 was decreased in CRC tissues and cell lines. Ectopic expression of miR-154 remarkably suppressed cell proliferation and colony formation, migration and invasion in CRC cells. The toll-like receptor 2 (TLR2) was found to be a direct target of miR-154 in CRC cells. Inhibition of TLR2 performed similar effects with miR-154 overexpression on CRC cells, and overexpression of TLR2 could significantly reverse the tumor suppressive effects of miR-154 on CRC cells. This study suggests an essential role for miR-154 in CRC.
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Affiliation(s)
- Chaoguang Xin
- Anus-Intestines Department, Daqing Oilfield General Hospital, Daqing, 163000, China
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TDP-43 regulates the microprocessor complex activity during in vitro neuronal differentiation. Mol Neurobiol 2013; 48:952-63. [PMID: 24113842 DOI: 10.1007/s12035-013-8564-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 09/22/2013] [Indexed: 12/12/2022]
Abstract
TDP-43 (TAR DNA-binding protein 43) is an RNA-binding protein implicated in RNA metabolism at several levels. Even if ubiquitously expressed, it is considered as a neuronal activity-responsive factor and a major signature for neurological pathologies, making the comprehension of its activity in the nervous system a very challenging issue. TDP-43 has also been described as an accessory component of the Drosha-DGCR8 (DiGeorge syndrome critical region gene 8) microprocessor complex, which is crucially involved in basal and tissue-specific RNA processing events. In the present study, we exploited in vitro neuronal differentiation systems to investigate the TDP-43 demand for the microprocessor function, focusing on both its canonical microRNA biosynthetic activity and its alternative role as a post-transcriptional regulator of gene expression. Our findings reveal a novel role for TDP-43 as an essential factor that controls the stability of Drosha protein during neuronal differentiation, thus globally affecting the production of microRNAs. We also demonstrate that TDP-43 is required for the Drosha-mediated regulation of Neurogenin 2, a master gene orchestrating neurogenesis, whereas post-transcriptional control of Dgcr8, another Drosha target, resulted to be TDP-43-independent. These results implicate a previously uncovered contribution of TDP-43 in regulating the abundance and the substrate specificity of the microprocessor complex and provide new insights into TDP-43 as a key player in neuronal differentiation.
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