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Kaminska D. The Role of RNA Splicing in Liver Function and Disease: A Focus on Metabolic Dysfunction-Associated Steatotic Liver Disease. Genes (Basel) 2024; 15:1181. [PMID: 39336772 PMCID: PMC11431473 DOI: 10.3390/genes15091181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2024] [Revised: 09/05/2024] [Accepted: 09/07/2024] [Indexed: 09/30/2024] Open
Abstract
RNA splicing is an essential post-transcriptional mechanism that facilitates the excision of introns and the connection of exons to produce mature mRNA, which is essential for gene expression and proteomic diversity. In the liver, precise splicing regulation is critical for maintaining metabolic balance, detoxification, and protein synthesis. This review explores the mechanisms of RNA splicing and the role of splicing factors, particularly in the context of Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD). This review also highlights how RNA splicing dysregulation can lead to aberrant splicing and impact the progression of liver diseases such as MASLD, with a particular focus on Metabolic Dysfunction-Associated Steatohepatitis (MASH), which represents the advanced stage of MASLD. Recent advances in the clinical application of antisense oligonucleotides (ASOs) to correct splicing errors offer promising therapeutic strategies for restoring normal liver function. Additionally, the dysregulation of splicing observed in liver diseases may serve as a potential diagnostic marker, offering new opportunities for early identification of individuals more susceptible to disease progression. This review provides insights into the molecular mechanisms that govern splicing regulation in the liver, with a particular emphasis on MASLD, and discusses potential therapeutic approaches targeting RNA splicing to treat MASLD and related metabolic disorders.
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Affiliation(s)
- Dorota Kaminska
- Department of Medicine, Division of Cardiology, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, CA 90095, USA
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2
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Luo J, Zhao S, Ren Q, Guan G, Luo J, Yin H. Role of Recognition MicroRNAs in Hemaphysalis longicornis and Theileria orientalis Interactions. Pathogens 2024; 13:288. [PMID: 38668243 PMCID: PMC11054001 DOI: 10.3390/pathogens13040288] [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: 01/31/2024] [Revised: 03/20/2024] [Accepted: 03/27/2024] [Indexed: 04/29/2024] Open
Abstract
Ticks are an important type of pathogen transmission vector, and pathogens not only cause serious harm to livestock but can also infect humans. Because of the roles that ticks play in disease transmission, reducing tick pathogen infectivity has become increasingly important and requires the identification and characterization of these pathogens and their interaction mechanisms. In this study, we determined the miRNA expression profile of Hemaphysalis longicornis infected with Theileria orientalis, predicted the target genes of miRNAs involved in this infection process, and investigated the role of miRNA target recognition during host-pathogen interactions. The results showed that longipain is a target gene of miR-5309, which was differentially expressed at different developmental stages and in various tissues in the control group. However, the miR-5309 level was reduced in the infection group. Analysis of the interaction between miRNA and the target gene showed that miR-5309 negatively regulated the expression of the longipain protein during the infection of H. longicornis with T. orientalis. To verify this inference, we compared longipain with the blocking agent orientalis. In this study, the expression of longipain was upregulated by the inhibition of miR-5309 in ticks, and the ability of the antibody produced by the tick-derived protein to attenuate T. orientalis infection was verified through animal immunity and antigen-antibody binding tests. The results showed that expression of the longipain + GST fusion protein caused the cattle to produce antibodies that could be successfully captured by ticks, and cellular immunity was subsequently activated in the ticks, resulting in a subtractive effect on T. orientalis infection. This research provides ideas for the control of ticks and tickborne diseases and a research basis for studying the mechanism underlying the interaction between ticks and pathogens.
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Affiliation(s)
- Jin Luo
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou 730046, China; (S.Z.); (Q.R.); (G.G.); (J.L.)
| | - Shuaiyang Zhao
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou 730046, China; (S.Z.); (Q.R.); (G.G.); (J.L.)
| | - Qiaoyun Ren
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou 730046, China; (S.Z.); (Q.R.); (G.G.); (J.L.)
| | - Guiquan Guan
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou 730046, China; (S.Z.); (Q.R.); (G.G.); (J.L.)
| | - Jianxun Luo
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou 730046, China; (S.Z.); (Q.R.); (G.G.); (J.L.)
| | - Hong Yin
- State Key Laboratory for Animal Disease Control and Prevention, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Science, Xujiaping 1, Lanzhou 730046, China; (S.Z.); (Q.R.); (G.G.); (J.L.)
- Jiangsu Co-Innovation Center for the Prevention and Control of Important Animal Infectious Disease and Zoonosis, Yangzhou University, Yangzhou 225009, China
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3
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Castellá M, Mestres-Arenas A, Gavaldà-Navarro A, Blasco-Roset A, Quesada-López T, Romero-Carramiñana I, Giralt M, Villarroya F, Cereijo R. The splicing factor SF3B1 is involved in brown adipocyte thermogenic activation. Biochem Pharmacol 2024; 220:116014. [PMID: 38158020 DOI: 10.1016/j.bcp.2023.116014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/21/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
The ability of alternative splicing mechanisms to control gene expression is increasingly being recognized as relevant for adipose tissue function. The expression of SF3B1, a key component of the SF3B complex directly involved in spliceosome formation, was previously reported to be significantly induced in brown adipose tissue under cold-induced thermogenic activation. Here, we identify that noradrenergic cAMP-mediated thermogenic stimulation increases SF3B1 expression in brown and beige adipocytes. We further show that pladienolide-B, a drug that binds SF3B1 to inhibit pre-mRNA splicing by targeting the SF3B complex, down-regulates key components of the thermogenic machinery (e.g., UCP1 gene expression), differentially alters the expression of alternative splicing-regulated transcripts encoding molecular actors involved in the oxidative metabolism of brown adipocytes (e.g., peroxisome proliferator-activated receptor-gamma co-activator-alpha [PGC-1α] and cytochrome oxidase subunit 7a genes), and impairs the respiratory activity of brown adipocytes. Similar alterations were found in brown adipocytes with siRNA-mediated knockdown of SF3B1 protein levels. Our findings collectively indicate that SF3B1 is a key factor in the appropriate thermogenic activation of differentiated brown adipocytes. This work exemplifies the importance of splicing processes in adaptive thermogenesis and suggests that pharmacological tools, such as pladienolide-B, may be used to modulate brown adipocyte thermogenic activity.
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Affiliation(s)
- Moisés Castellá
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain
| | - Alberto Mestres-Arenas
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain
| | - Aleix Gavaldà-Navarro
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain
| | - Albert Blasco-Roset
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain
| | - Tania Quesada-López
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain; Institut d'Investigació Biomèdica Sant Pau (IIB-SANT PAU), and Department of Infectious Diseases, Hospital de la Santa Creu i Sant Pau, 08041 Barcelona, Spain
| | - Inés Romero-Carramiñana
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid (CSIC-UAM); Instituto de Investigación Hospital 12 de Octubre, Universidad Autónoma de Madrid; and Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER) ISCIII, 28049 Madrid, Spain
| | - Marta Giralt
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain
| | - Francesc Villarroya
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain.
| | - Rubén Cereijo
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona; Institut de Biomedicina de la Universitat de Barcelona (IBUB); and Institut de Recerca de Sant Joan de Déu, 08028 Barcelona, Spain; CIBER Fisiopatología de la Obesidad y Nutrición, 28029 Madrid, Spain.
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4
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Naing YT, Sun L. The Role of Splicing Factors in Adipogenesis and Thermogenesis. Mol Cells 2023; 46:268-277. [PMID: 37170770 PMCID: PMC10183792 DOI: 10.14348/molcells.2023.2195] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 02/27/2023] [Accepted: 03/03/2023] [Indexed: 05/13/2023] Open
Abstract
Obesity is a significant global health risk that can cause a range of serious metabolic problems, such as type 2 diabetes and cardiovascular diseases. Adipose tissue plays a pivotal role in regulating energy and lipid storage. New research has underlined the crucial role of splicing factors in the physiological and functional regulation of adipose tissue. By generating multiple transcripts from a single gene, alternative splicing allows for a greater diversity of the proteome and transcriptome, which subsequently influence adipocyte development and metabolism. In this review, we provide an outlook on the part of splicing factors in adipogenesis and thermogenesis, and investigate how the different spliced isoforms can affect the development and function of adipose tissue.
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Affiliation(s)
- Yadanar Than Naing
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore 169857
| | - Lei Sun
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore 169857
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5
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Li N, Li Y, Han X, Zhang J, Han J, Jiang X, Wang W, Xu Y, Xu Y, Fu Y, Si S. LXR agonist inhibits inflammation through regulating MyD88 mRNA alternative splicing. Front Pharmacol 2022; 13:973612. [PMID: 36313296 PMCID: PMC9614042 DOI: 10.3389/fphar.2022.973612] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 09/22/2022] [Indexed: 12/02/2022] Open
Abstract
Liver X receptors (LXRs) are important regulators of cholesterol metabolism and inflammatory responses. LXR agonists exhibit potently anti-inflammatory effects in macrophages, which make them beneficial to anti-atherogenic therapy. In addition to transrepressive regulation by SUMOylation, LXRs can inhibit inflammation by various mechanisms through affecting multiple targets. In this study, we found that the classic LXR agonist T0901317 mediated numerous genes containing alternative splice sites, including myeloid differentiation factor 88 (MyD88), that contribute to inflammatory inhibition in RAW264.7 macrophages. Furthermore, T0901317 increased level of alternative splice short form of MyD88 mRNA by down-regulating expression of splicing factor SF3A1, leading to nuclear factor κB-mediated inhibition of inflammation. In conclusion, our results suggest for the first time that the LXR agonist T0901317 inhibits lipopolysaccharide-induced inflammation through regulating MyD88 mRNA alternative splicing involved in TLR4 signaling pathway.
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Affiliation(s)
- Ni Li
- State Key Laboratory of Bioactive Substances and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, China
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- *Correspondence: Ni Li, ; Yu Fu, ; Shuyi Si,
| | - Yan Li
- College of Food Science and Biology, Hebei University of Science and Technology, Shijiazhuang, Hebei
| | - Xiaowan Han
- State Key Laboratory of Bioactive Substances and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences, Beijing, China
| | - Jing Zhang
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Jiangxue Han
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xinhai Jiang
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Weizhi Wang
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yang Xu
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yanni Xu
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Yu Fu
- College of Food Science and Biology, Hebei University of Science and Technology, Shijiazhuang, Hebei
- *Correspondence: Ni Li, ; Yu Fu, ; Shuyi Si,
| | - Shuyi Si
- NHC Key Laboratory of Biotechnology of Antibiotics, Institute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
- *Correspondence: Ni Li, ; Yu Fu, ; Shuyi Si,
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6
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Nova1 or Bim Deficiency in Pancreatic β-Cells Does Not Alter Multiple Low-Dose Streptozotocin-Induced Diabetes and Diet-Induced Obesity in Mice. Nutrients 2022; 14:nu14183866. [PMID: 36145242 PMCID: PMC9500891 DOI: 10.3390/nu14183866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 11/17/2022] Open
Abstract
The loss of functional pancreatic β-cell mass is an important hallmark of both type 1 and type 2 diabetes. The RNA-binding protein NOVA1 is expressed in human and rodent pancreatic β-cells. Previous in vitro studies indicated that NOVA1 is necessary for glucose-stimulated insulin secretion and its deficiency-enhanced cytokine-induced apoptosis. Moreover, Bim, a proapoptotic protein, is differentially spliced and potentiates apoptosis in NOVA1-deficient β-cells in culture. We generated two novel mouse models by Cre-Lox technology lacking Nova1 (βNova1-/-) or Bim (βBim-/-) in β-cells. To test the impact of Nova1 or Bim deletion on β-cell function, mice were subjected to multiple low-dose streptozotocin (MLD-STZ)-induced diabetes or high-fat diet-induced insulin resistance. β-cell-specific Nova1 or Bim deficiency failed to affect diabetes development in response to MLD-STZ-induced β-cell dysfunction and death evidenced by unaltered blood glucose levels and pancreatic insulin content. In addition, body composition, glucose and insulin tolerance test, and pancreatic insulin content were indistinguishable between control and βNova1-/- or βBim-/- mice on a high fat diet. Thus, Nova1 or Bim deletion in β-cells does not impact on glucose homeostasis or diabetes development in mice. Together, these data argue against an in vivo role for the Nova1-Bim axis in β-cells.
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7
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Liu Q, Fang L, Wu C. Alternative Splicing and Isoforms: From Mechanisms to Diseases. Genes (Basel) 2022; 13:genes13030401. [PMID: 35327956 PMCID: PMC8951537 DOI: 10.3390/genes13030401] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 11/16/2022] Open
Abstract
Alternative splicing of pre-mRNA is a key mechanism for increasing the complexity of proteins in humans, causing a diversity of expression of transcriptomes and proteomes in a tissue-specific manner. Alternative splicing is regulated by a variety of splicing factors. However, the changes and errors of splicing regulation caused by splicing factors are strongly related to many diseases, something which represents one of this study’s main interests. Further understanding of alternative splicing regulation mediated by cellular factors is also a prospective choice to develop specific drugs for targeting the dynamic RNA splicing process. In this review, we firstly concluded the basic principle of alternative splicing. Afterwards, we showed how splicing isoforms affect physiological activities through specific disease examples. Finally, the available treatment methods relative to adjusting splicing activities have been summarized.
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Clark KC, Kwitek AE. Multi-Omic Approaches to Identify Genetic Factors in Metabolic Syndrome. Compr Physiol 2021; 12:3045-3084. [PMID: 34964118 PMCID: PMC9373910 DOI: 10.1002/cphy.c210010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Metabolic syndrome (MetS) is a highly heritable disease and a major public health burden worldwide. MetS diagnosis criteria are met by the simultaneous presence of any three of the following: high triglycerides, low HDL/high LDL cholesterol, insulin resistance, hypertension, and central obesity. These diseases act synergistically in people suffering from MetS and dramatically increase risk of morbidity and mortality due to stroke and cardiovascular disease, as well as certain cancers. Each of these component features is itself a complex disease, as is MetS. As a genetically complex disease, genetic risk factors for MetS are numerous, but not very powerful individually, often requiring specific environmental stressors for the disease to manifest. When taken together, all sequence variants that contribute to MetS disease risk explain only a fraction of the heritable variance, suggesting additional, novel loci have yet to be discovered. In this article, we will give a brief overview on the genetic concepts needed to interpret genome-wide association studies (GWAS) and quantitative trait locus (QTL) data, summarize the state of the field of MetS physiological genomics, and to introduce tools and resources that can be used by the physiologist to integrate genomics into their own research on MetS and any of its component features. There is a wealth of phenotypic and molecular data in animal models and humans that can be leveraged as outlined in this article. Integrating these multi-omic QTL data for complex diseases such as MetS provides a means to unravel the pathways and mechanisms leading to complex disease and promise for novel treatments. © 2022 American Physiological Society. Compr Physiol 12:1-40, 2022.
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Affiliation(s)
- Karen C Clark
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Anne E Kwitek
- Department of Physiology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
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9
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Wang H, Chan TW, Vashisht AA, Drew BG, Calkin AC, Harris TE, Wohlschlegel JA, Xiao X, Reue K. Lipin 1 modulates mRNA splicing during fasting adaptation in liver. JCI Insight 2021; 6:e150114. [PMID: 34494556 PMCID: PMC8492312 DOI: 10.1172/jci.insight.150114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 07/23/2021] [Indexed: 01/03/2023] Open
Abstract
Lipin 1 regulates cellular lipid homeostasis through roles in glycerolipid synthesis (through phosphatidic acid phosphatase activity) and transcriptional coactivation. Lipin 1-deficient individuals exhibit episodic disease symptoms that are triggered by metabolic stress, such as stress caused by prolonged fasting. We sought to identify critical lipin 1 activities during fasting. We determined that lipin 1 deficiency induces widespread alternative mRNA splicing in liver during fasting, much of which is normalized by refeeding. The role of lipin 1 in mRNA splicing was largely independent of its enzymatic function. We identified interactions between lipin 1 and spliceosome proteins, as well as a requirement for lipin 1 to maintain homeostatic levels of spliceosome small nuclear RNAs and specific RNA splicing factors. In fasted Lpin1-/- liver, we identified a correspondence between alternative splicing of phospholipid biosynthetic enzymes and dysregulated phospholipid levels; splicing patterns and phospholipid levels were partly normalized by feeding. Thus, lipin 1 influences hepatic lipid metabolism through mRNA splicing, as well as through enzymatic and transcriptional activities, and fasting exacerbates the deleterious effects of lipin 1 deficiency on metabolic homeostasis.
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Affiliation(s)
- Huan Wang
- Human Genetics, David Geffen School of Medicine at UCLA
| | | | - Ajay A Vashisht
- Biological Chemistry, University of California, Los Angeles, California, USA
| | - Brian G Drew
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia
| | - Anna C Calkin
- Baker Heart and Diabetes Institute, Melbourne, Victoria, Australia.,Central Clinical School, Monash University, Melbourne, Victoria, Australia.,Baker Department of Cardiometabolic Health, University of Melbourne, Parkville, Victoria, Australia
| | - Thurl E Harris
- Pharmacology, University of Virginia, Charlottesville, Virginia, USA
| | - James A Wohlschlegel
- Biological Chemistry, University of California, Los Angeles, California, USA.,Molecular Biology Institute and
| | - Xinshu Xiao
- Bioinformatics Interdepartmental Program and.,Molecular Biology Institute and.,Integrative Biology and Physiology, University of California, Los Angeles, California, USA
| | - Karen Reue
- Human Genetics, David Geffen School of Medicine at UCLA,,Molecular Biology Institute and
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The splicing factor XAB2 interacts with ERCC1-XPF and XPG for R-loop processing. Nat Commun 2021; 12:3153. [PMID: 34039990 PMCID: PMC8155215 DOI: 10.1038/s41467-021-23505-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 04/27/2021] [Indexed: 12/11/2022] Open
Abstract
RNA splicing, transcription and the DNA damage response are intriguingly linked in mammals but the underlying mechanisms remain poorly understood. Using an in vivo biotinylation tagging approach in mice, we show that the splicing factor XAB2 interacts with the core spliceosome and that it binds to spliceosomal U4 and U6 snRNAs and pre-mRNAs in developing livers. XAB2 depletion leads to aberrant intron retention, R-loop formation and DNA damage in cells. Studies in illudin S-treated cells and Csbm/m developing livers reveal that transcription-blocking DNA lesions trigger the release of XAB2 from all RNA targets tested. Immunoprecipitation studies reveal that XAB2 interacts with ERCC1-XPF and XPG endonucleases outside nucleotide excision repair and that the trimeric protein complex binds RNA:DNA hybrids under conditions that favor the formation of R-loops. Thus, XAB2 functionally links the spliceosomal response to DNA damage with R-loop processing with important ramifications for transcription-coupled DNA repair disorders. XPA-binding protein (XAB)-2 is the human homologue of the yeast pre-mRNA splicing factor Syf1. Here the authors use an in vivo biotinylation tagging approach to show XAB2’s role in DNA repair, RNA splicing and transcription during mammalian development.
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Touir A, Boumiza S, Nasr HB, Bchir S, Tabka Z, Norel X, Chahed K. Prostaglandin Endoperoxide H Synthase-2 (PGHS-2) Variants and Risk of Obesity and Microvascular Dysfunction Among Tunisians: Relevance of rs5277 (306G/C) and rs5275 (8473T/C) Genetic Markers. Biochem Genet 2021; 59:1457-1486. [PMID: 33929697 DOI: 10.1007/s10528-021-10071-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2020] [Accepted: 04/19/2021] [Indexed: 10/21/2022]
Abstract
The purpose of this study was to determine the impact of six PGHS-2 genetic variants on obesity development and microvascular dysfunction. The study included 305 Tunisian subjects (186 normal weights, 35 overweights and 84 obeses). PCR analyses were used for allelic discrimination between polymorphisms. Prostaglandin (PGE2, PGI2), leptin, and matrix metalloproteinase (MMP1, 2, 3, 9) levels were evaluated by ELISA. Fatty acid composition was performed by gas chromatography-mass spectrometry. Our results revealed that subjects carrying the PGHS-2 306CC (rs5277) and 8473CC (rs5275) genotypes present higher anthropometric values compared to wild-type genotypes (306GG, BMI (Kg/m2): 27.11 ± 0.58; WC (cm): 93.09 ± 1.58; 306CC, BMI: 33.83 ± 2.46; WC: 109.93 ± 5.41; 8473TT, BMI: 27.75 ± 0.68; WC: 93.96 ± 1.75; 8473CC, BMI: 33.72 ± 2.2; WC: 117.89 ± 2.94). A reduced microvascular reactivity and a higher PGE2 level were also found in individuals with the 306CC and 8473CC genotypes in comparison to 306GG and 8473TT carriers (306GG, Peak Ach-CVC (PU/mmHg): 0.46 ± 0.03; PGE2 (pg/ml): 7933.1 ± 702; 306CC, Peak Ach-CVC: 0.24 ± 0.01; PGE2: 13,380.3 ± 966.2; 8473TT, Peak Ach-CVC: 0.48 ± 0.05; PGE2: 7086.41 ± 700.31; 8473CC, Peak Ach-CVC: 0.23 ± 0.01; PGE2: 13,175.7 ± 1165.8). Fatty acid analysis showed a significant increase of palmitic acid (PA) (34.2 ± 2.09 vs. 16.82% ± 1.76, P < 0.001), stearic acid (SA) (25.76 ± 3.29 vs. 9.05% ± 2.53, P < 0.001), and linoleic acid (LA) (5.25 ± 1.18 vs. 0.5% ± 0.09, P < 0.001) levels in individuals carrying the PGHS-2 306CC genotype when compared to GG genotype individuals. Subjects with the 8473CC genotype showed also a significant increase of PA, SA ,and LA levels when compared to TT genotype carriers (PA: 38.02 ± 1.51 vs. 12.65% ± 1.54, P < 0.001; SA: 32.96 ± 1.87 vs. 1.38% ± 0.56, P < 0.001; LA: 26.84 ± 2.09 vs. 3.7% ± 1.54, P < 0.001). Logistic regression analysis revealed that PGHS-2 306CC and 8473CC variants are significantly associated with obesity status (OR 6.25, CI (1.8-21.6), P = 0.004; OR 3.01, CI (1.13-8.52), P = 0.03, respectively). Haplotypes containing the C306:T8473 (OR 2.91; P = 0.01) and G306:C8473 (OR 5.25; P = 0.002) combinations were associated with an enhanced risk for obesity development in the studied population. In conclusion, our results highlight that PGHS-2 306G/C and 8473T/C variants could be useful indicators of obesity development, inflammation, and microvascular dysfunction among Tunisians.
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Affiliation(s)
- Ahlem Touir
- Institut Supérieur de Biotechnologie de Monastir, Université de Monastir, Avenue Tahar Hadded, BP 74, 5000, Monastir, Tunisia. .,Laboratoire de Recherche LR19ES09, Physiologie de L'Exercice Et Physiopathologie: de L'Intégré Au Moléculaire "Biologie, Médecine Et Santé, Université de Sousse, Sousse, Tunisia.
| | - Soumaya Boumiza
- Laboratoire de Recherche LR19ES09, Physiologie de L'Exercice Et Physiopathologie: de L'Intégré Au Moléculaire "Biologie, Médecine Et Santé, Université de Sousse, Sousse, Tunisia
| | - Hela Ben Nasr
- Laboratoire de Recherche LR19ES09, Physiologie de L'Exercice Et Physiopathologie: de L'Intégré Au Moléculaire "Biologie, Médecine Et Santé, Université de Sousse, Sousse, Tunisia.,Institut Des Sciences Infirmières, Sousse, Tunisia
| | - Sarra Bchir
- Laboratoire de Recherche LR19ES09, Physiologie de L'Exercice Et Physiopathologie: de L'Intégré Au Moléculaire "Biologie, Médecine Et Santé, Université de Sousse, Sousse, Tunisia
| | - Zouhair Tabka
- Laboratoire de Recherche LR19ES09, Physiologie de L'Exercice Et Physiopathologie: de L'Intégré Au Moléculaire "Biologie, Médecine Et Santé, Université de Sousse, Sousse, Tunisia
| | - Xavier Norel
- INSERM U1148, Laboratory for Vascular Translational Science, CHU X. Bichat, 46 rue Huchard, 75018, Paris, France
| | - Karim Chahed
- Laboratoire de Recherche LR19ES09, Physiologie de L'Exercice Et Physiopathologie: de L'Intégré Au Moléculaire "Biologie, Médecine Et Santé, Université de Sousse, Sousse, Tunisia.,Faculté Des Sciences de Sfax, Université de Sfax, Sfax, Tunisia
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12
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Wu P, Zhang M, Webster NJG. Alternative RNA Splicing in Fatty Liver Disease. Front Endocrinol (Lausanne) 2021; 12:613213. [PMID: 33716968 PMCID: PMC7953061 DOI: 10.3389/fendo.2021.613213] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 01/13/2021] [Indexed: 12/12/2022] Open
Abstract
Alternative RNA splicing is a process by which introns are removed and exons are assembled to construct different RNA transcript isoforms from a single pre-mRNA. Previous studies have demonstrated an association between dysregulation of RNA splicing and a number of clinical syndromes, but the generality to common disease has not been established. Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease affecting one-third of adults worldwide, increasing the risk of cirrhosis and hepatocellular carcinoma (HCC). In this review we focus on the change in alternative RNA splicing in fatty liver disease and the role for splicing regulation in disease progression.
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Affiliation(s)
- Panyisha Wu
- Department of Medicine, Division of Endocrinology and Metabolism, University of California San Diego, La Jolla, CA, United States
| | - Moya Zhang
- University of California Los Angeles, Los Angeles, CA, United States
| | - Nicholas J. G. Webster
- VA San Diego Healthcare System, San Diego, CA, United States
- Department of Medicine, Division of Endocrinology and Metabolism, University of California San Diego, La Jolla, CA, United States
- Moores Cancer Center, University of California, San Diego, La Jolla, CA, United States
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13
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Cote JL, Argetsinger LS, Flores A, Rupp AC, Cline JM, DeSantis LC, Bedard AH, Bagchi DP, Vander PB, Cacciaglia AM, Clutter ES, Chandrashekar G, MacDougald OA, Myers MG, Carter-Su C. Deletion of the Brain-Specific α and δ Isoforms of Adapter Protein SH2B1 Protects Mice From Obesity. Diabetes 2021; 70:400-414. [PMID: 33214137 PMCID: PMC7881872 DOI: 10.2337/db20-0687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/12/2020] [Indexed: 11/13/2022]
Abstract
Mice lacking SH2B1 and humans with variants of SH2B1 display severe obesity and insulin resistance. SH2B1 is an adapter protein that is recruited to the receptors of multiple hormones and neurotrophic factors. Of the four known alternatively spliced SH2B1 isoforms, SH2B1β and SH2B1γ exhibit ubiquitous expression, whereas SH2B1α and SH2B1δ are essentially restricted to the brain. To understand the roles for SH2B1α and SH2B1δ in energy balance and glucose metabolism, we generated mice lacking these brain-specific isoforms (αδ knockout [αδKO] mice). αδKO mice exhibit decreased food intake, protection from weight gain on standard and high-fat diets, and an adiposity-dependent improvement in glucose homeostasis. SH2B1 has been suggested to impact energy balance via the modulation of leptin action. However, αδKO mice exhibit leptin sensitivity that is similar to that of wild-type mice by multiple measures. Thus, decreasing the abundance of SH2B1α and/or SH2B1δ relative to the other SH2B1 isoforms likely shifts energy balance toward a lean phenotype via a primarily leptin-independent mechanism. Our findings suggest that the different alternatively spliced isoforms of SH2B1 perform different functions in vivo.
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Affiliation(s)
- Jessica L Cote
- Neuroscience Program, University of Michigan Medical School, Ann Arbor, MI
| | - Lawrence S Argetsinger
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Anabel Flores
- Cell and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI
| | - Alan C Rupp
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI
| | - Joel M Cline
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Lauren C DeSantis
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Alexander H Bedard
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Devika P Bagchi
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Paul B Vander
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Abrielle M Cacciaglia
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Erik S Clutter
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Gowri Chandrashekar
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
| | - Ormond A MacDougald
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
- Cell and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI
| | - Martin G Myers
- Neuroscience Program, University of Michigan Medical School, Ann Arbor, MI
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
- Cell and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI
| | - Christin Carter-Su
- Neuroscience Program, University of Michigan Medical School, Ann Arbor, MI
- Department of Molecular and Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI
- Cell and Molecular Biology Program, University of Michigan Medical School, Ann Arbor, MI
- Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI
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14
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Louis JM, Agarwal A, Aduri R, Talukdar I. Global analysis of RNA-protein interactions in TNF-α induced alternative splicing in metabolic disorders. FEBS Lett 2021; 595:476-490. [PMID: 33417721 DOI: 10.1002/1873-3468.14029] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2020] [Revised: 11/26/2020] [Accepted: 12/10/2020] [Indexed: 12/27/2022]
Abstract
In this report, using the database of RNA-binding protein specificities (RBPDB) and our previously published RNA-seq data, we analyzed the interactions between RNA and RNA-binding proteins to decipher the role of alternative splicing in metabolic disorders induced by TNF-α. We identified 13 395 unique RNA-RBP interactions, including 385 unique RNA motifs and 35 RBPs, some of which (including MBNL-1 and 3, ZFP36, ZRANB2, and SNRPA) are transcriptionally regulated by TNF-α. In addition to some previously reported RBPs, such as RBMX and HuR/ELAVL1, we found a few novel RBPs, such as ZRANB2 and SNRPA, to be involved in the regulation of metabolic syndrome-associated genes that contain an enrichment of tetrameric RNA sequences (AUUU). Taken together, this study paves the way for novel RNA-protein interaction-based therapeutics for treating metabolic syndromes.
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Affiliation(s)
- Jiss Maria Louis
- Department of Biological Sciences, BITS Pilani, Zuarinagar, India
| | - Arjun Agarwal
- Department of Computer Science, BITS Pilani, Zuarinagar, India
| | - Raviprasad Aduri
- Department of Biological Sciences, BITS Pilani, Zuarinagar, India
| | - Indrani Talukdar
- Department of Biological Sciences, BITS Pilani, Zuarinagar, India
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15
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Maftei D, Lattanzi R, Vincenzi M, Squillace S, Fullone MR, Miele R. The balance of concentration between Prokineticin 2β and Prokineticin 2 modulates the food intake by STAT3 signaling. BBA ADVANCES 2021; 1:100028. [PMID: 37082024 PMCID: PMC10074905 DOI: 10.1016/j.bbadva.2021.100028] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 10/01/2021] [Accepted: 10/05/2021] [Indexed: 12/31/2022] Open
Abstract
The secreted bioactive peptide prokineticin 2 (PK2) is a potent adipokine and its central and peripheral administration reduces food intake in rodents. The pk2 gene has two splice variants, PK2 and PK2L (PK2 long form), which is cleaved into an active peptide, PK2β, that preferentially binds prokineticin receptor 1 (PKR1). We investigated the role of PK2β in the regulation of food intake. We demonstrated that intraperitoneal injection of PK2β, in contrast to PK2, did not reduce food intake in mice. Exposure of hypotalamic explants to PK2, but not PK2β, induced phosphorylation of STAT3 and ERK. We also evidenced that in adipocytes from PKR1 knock-out mice, a model of obesity, there were higher PK2β levels than PK2 inducing a decreased activation of STAT3 and ERK. Our results suggest that variations in PK2 and PK2β levels, due to modulation of pk2 gene splicing processes, affect food intake in mice.
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Affiliation(s)
- Daniela Maftei
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Roberta Lattanzi
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
- Corresponding author: Roberta Lattanzi, Department of Physiology and Pharmacology “Vittorio Erspamer” Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy.
| | - Martina Vincenzi
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Silvia Squillace
- Department of Physiology and Pharmacology “Vittorio Erspamer”, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Maria Rosaria Fullone
- Department of Biochemical Sciences “A. Rossi Fanelli” and CNR-Institute of Molecular Biology and Pathology, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Rossella Miele
- Department of Biochemical Sciences “A. Rossi Fanelli” and CNR-Institute of Molecular Biology and Pathology, Sapienza University of Rome, Piazzale Aldo Moro 5, I-00185 Rome, Italy
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16
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Duodenal Metatranscriptomics to Define Human and Microbial Functional Alterations Associated with Severe Obesity: A Pilot Study. Microorganisms 2020; 8:microorganisms8111811. [PMID: 33213098 PMCID: PMC7698607 DOI: 10.3390/microorganisms8111811] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Revised: 11/14/2020] [Accepted: 11/16/2020] [Indexed: 12/12/2022] Open
Abstract
Obesity is a multifactorial disorder, and the gut microbiome has been suggested to contribute to its onset. In order to better clarify the role of the microbiome in obesity, we evaluated the metatranscriptome in duodenal biopsies from a cohort of 23 adult severely obese and lean control subjects using next generation sequencing. Our aim was to provide a general picture of the duodenal metatranscriptome associated with severe obesity. We found altered expressions of human and microbial genes in the obese compared to lean subjects, with most of the gene alterations being present in the carbohydrate, protein, and lipid metabolic pathways. Defects were also present in several human genes involved in epithelial intestinal cells differentiation and function, as well as in the immunity/inflammation pathways. Moreover, the microbial taxa abundance inferred by our transcriptomic data differed in part from the data that we previously evaluated by 16S rRNA in 13/23 individuals of our cohort, particularly concerning the Firmicutes and Proteobacteria phyla abundances. In conclusion, our pilot study provides the first taxonomic and functional characterization of duodenal microbiota in severely obese subjects and lean controls. Our findings suggest that duodenal microbiome and human genes both play a role in deregulating metabolic pathways, likely affecting energy metabolism and thus contributing to the obese phenotype.
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17
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Stolzenbach F, Valdivia S, Ojeda-Provoste P, Toledo F, Sobrevia L, Kerr B. DNA methylation changes in genes coding for leptin and insulin receptors during metabolic-altered pregnancies. Biochim Biophys Acta Mol Basis Dis 2020; 1866:165465. [DOI: 10.1016/j.bbadis.2019.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 03/19/2019] [Accepted: 05/02/2019] [Indexed: 01/07/2023]
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18
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Sequence and Evolutionary Features for the Alternatively Spliced Exons of Eukaryotic Genes. Int J Mol Sci 2019; 20:ijms20153834. [PMID: 31390737 PMCID: PMC6695735 DOI: 10.3390/ijms20153834] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 07/25/2019] [Accepted: 07/31/2019] [Indexed: 12/22/2022] Open
Abstract
Alternative splicing of pre-mRNAs is a crucial mechanism for maintaining protein diversity in eukaryotes without requiring a considerable increase of genes in the number. Due to rapid advances in high-throughput sequencing technologies and computational algorithms, it is anticipated that alternative splicing events will be more intensively studied to address different kinds of biological questions. The occurrences of alternative splicing mean that all exons could be classified to be either constitutively or alternatively spliced depending on whether they are virtually included into all mature mRNAs. From an evolutionary point of view, therefore, the alternatively spliced exons would have been associated with distinctive biological characteristics in comparison with constitutively spliced exons. In this paper, we first outline the representative types of alternative splicing events and exon classification, and then review sequence and evolutionary features for the alternatively spliced exons. The main purpose is to facilitate understanding of the biological implications of alternative splicing in eukaryotes. This knowledge is also helpful to establish computational approaches for predicting the splicing pattern of exons.
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19
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Dlamini Z, Hull R, Makhafola TJ, Mbele M. Regulation of alternative splicing in obesity-induced hypertension. Diabetes Metab Syndr Obes 2019; 12:1597-1615. [PMID: 31695458 PMCID: PMC6718130 DOI: 10.2147/dmso.s188680] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 02/11/2019] [Indexed: 12/26/2022] Open
Abstract
Obesity is the result of genetics which predisposes an individual to obesity and environmental factors, resulting in excessive weight gain. A well-established linear relationship exists between hypertension and obesity. The combined burden of hypertension and obesity poses significant health and economic challenges. Many environmental factors and genetic traits interact to contribute to obesity-linked hypertension. These include excess sodium re-absorption or secretion by the kidneys, a hypertensive shift of renal-pressure and activation of the sympathetic nervous system. Most individuals suffering from hypertension need drugs in order to treat their raised blood pressure, and while a number of antihypertensive therapeutic agents are currently available, 50% of cases remain uncontrolled. In order to develop new and effective therapeutic agents combating obesity-induced hypertension, a thorough understanding of the molecular events leading to adipogenesis is critical. With the advent of whole genome and exome sequencing techniques, new genes and variants which can be used as markers for obesity and hypertension are being identified. This review examines the role played by alternative splicing (AS) as a contributing factor to the metabolic regulation of obesity-induced hypertension. Splicing mutations constitute at least 14% of the disease-causing mutations, thus implicating polymorphisms that effect splicing as indicators of disease susceptibility. The unique transcripts resulting from the alternate splicing of mRNA encoding proteins that play a key role in contributing to obesity would be vital to gain a proper understanding of the genetic causes of obesity. A greater knowledge of the genetic basis for obesity-linked hypertension will assist in the development of appropriate diagnostic tests as well as the identification of new personalized therapeutic targets against obesity-induced hypertension.
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Affiliation(s)
- Zodwa Dlamini
- South African Medical Research Council/University of Pretoria Precision Prevention & Novel Drug Targets for HIV-Associated Cancers (PPNDTHAC) Extramural Unit, Pan African Cancer Research Institute (PACRI), Faculty of Health Sciences, University of Pretoria, Hatfield0028, South Africa
- Correspondence: Zodwa Dlamini South African Medical Research Council/University of Pretoria Precision Prevention & Novel Drug Targets for HIV-Associated Cancers (PPNDTHAC) Extramural Unit, Pan African Cancer Research Institute (PACRI), Faculty of Health Sciences, University of Pretoria, South AfricaTel +27 3 18 199 334/5Email
| | - Rodney Hull
- South African Medical Research Council/University of Pretoria Precision Prevention & Novel Drug Targets for HIV-Associated Cancers (PPNDTHAC) Extramural Unit, Pan African Cancer Research Institute (PACRI), Faculty of Health Sciences, University of Pretoria, Hatfield0028, South Africa
| | - Tshepiso J Makhafola
- South African Medical Research Council/University of Pretoria Precision Prevention & Novel Drug Targets for HIV-Associated Cancers (PPNDTHAC) Extramural Unit, Pan African Cancer Research Institute (PACRI), Faculty of Health Sciences, University of Pretoria, Hatfield0028, South Africa
| | - Mzwandile Mbele
- South African Medical Research Council/University of Pretoria Precision Prevention & Novel Drug Targets for HIV-Associated Cancers (PPNDTHAC) Extramural Unit, Pan African Cancer Research Institute (PACRI), Faculty of Health Sciences, University of Pretoria, Hatfield0028, South Africa
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20
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Fan H, Chen S, Gao B, Ding S, Zhao Q, Li C, Asakawa T. Risk analysis of systemic levels of estrogen and adipokines as well as estrogen receptors from PBMCs in childbearing and perimenopausal women with obesity. Diabetes Metab Syndr Obes 2019; 12:1287-1295. [PMID: 31534355 PMCID: PMC6682318 DOI: 10.2147/dmso.s206069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Accepted: 07/04/2019] [Indexed: 12/12/2022] Open
Abstract
PURPOSE We aimed to evaluate the clinical value of systemic levels of estrogen and adipokines as well as estrogen receptors from peripheral blood mononuclear cells (PBMCs) in childbearing and perimenopausal women with obesity. SUBJECTS AND METHODS We observed 292 women, including 160 perimenopausal women (80 with obesity and 80 without obesity) and 132 women of childbearing age (67 with obesity and 65 without obesity). Body parameters, such as body mass index and waist circumference, were measured. Fat distribution was evaluated using a computerized tomography scanner. The levels of serum estrogen, leptin, visfatin, and adiponectin were measured using an enzyme-linked immunosorbent assay. The expression of circulating ERs was evaluated by Western blot analysis. RESULTS Perimenopausal women and childbearing women with obesity exhibited lower levels of estrogen and adiponectin, in addition to a distribution of visceral fat with higher levels of leptin and visfatin. These findings reflect the current data of menopausal women, which confirms the reliability of this experimental system. However, the expression of ERα in peripheral blood was significantly enhanced in women with obesity of both childbearing and perimenopausal age. This result is contrary to the common understanding of adipose tissue, namely that ERα is protective. The expression of ERβ in the women without obesity of both childbearing and perimenopausal age was higher than in women with obesity, which coincides with the results of a previous study on adipose tissue. CONCLUSION Our data fundamentally contradicts the utility of circulating ERα and ERα/ERβ evaluations in obesity studies. Because estrogen exerts pleiotropic effects on multiple tissues in the body through differential regulation of ERs, although the expression of ERβ coincides with the results of a previous study on adipose tissue, the expression levels of ERs in blood cannot be used as a diagnostic of informative tool for obesity in women.
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Affiliation(s)
- Huijuan Fan
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
| | - Shujiao Chen
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
- Department of Internal Medicine, The Third People’s Hospital Affiliated to Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
- Shujiao ChenResearch Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, No.1 Qiuyang Road, Shangjie town, Fuzhou, Minhou District350122, People’s Republic of ChinaTel +86 5 912 286 1989Fax +86 5 912 286 1989Email
| | - Bizhen Gao
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
| | - Shanshan Ding
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
| | - Qiang Zhao
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
| | - Candong Li
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
| | - Tetsuya Asakawa
- Research Base of Traditional Chinese Medicine Syndrome, Fujian University of Traditional Chinese Medicine, Fuzhou, Shangjie Minhou350122, People’s Republic of China
- Department of Neurosurgery, Hamamatsu University School of Medicine, Hamamatsu-city, Shizuoka431-3192, Japan
- Correspondence: Tetsuya AsakawaDepartment of Neurosurgery, Hamamatsu University School of Medicine, Handayama, 1-20-1, Higashi-ku, Hamamatsu-city, Shizuoka431-3192, JapanTel +81 53 435 2283Fax +81 53 435 2282Email
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Annalora AJ, Jozic M, Marcus CB, Iversen PL. Alternative splicing of the vitamin D receptor modulates target gene expression and promotes ligand-independent functions. Toxicol Appl Pharmacol 2018; 364:55-67. [PMID: 30552932 DOI: 10.1016/j.taap.2018.12.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Revised: 12/04/2018] [Accepted: 12/10/2018] [Indexed: 02/07/2023]
Abstract
Alternative splicing modulates gene function by creating splice variants with alternate functions or non-coding RNA activity. Naturally occurring variants of nuclear receptor (NR) genes with dominant negative or gain-of-function phenotypes have been documented, but their cellular roles, regulation, and responsiveness to environmental stress or disease remain unevaluated. Informed by observations that class I androgen and estrogen receptor variants display ligand-independent signaling in human cancer tissues, we questioned whether the function of class II NRs, like the vitamin D receptor (VDR), would also respond to alternative splicing regulation. Artificial VDR constructs lacking exon 3 (Dex3-VDR), encoding part of the DNA binding domain (DBD), and exon 8 (Dex8-VDR), encoding part of the ligand binding domain (LBD), were transiently transfected into DU-145 cells and stably-integrated into Caco-2 cells to study their effect on gene expression and cell viability. Changes in VDR promoter signaling were monitored by the expression of target genes (e.g. CYP24A1, CYP3A4 and CYP3A5). Ligand-independent VDR signaling was observed in variants lacking exon 8, and a significant loss of gene suppressor function was documented for variants lacking exon 3. The gain-of-function behavior of the Dex8-VDR variant was recapitulated in vitro using antisense oligonucleotides (ASO) that induce the skipping of exon 8 in wild-type VDR. ASO targeting the splice acceptor site of exon 8 significantly stimulated ligand-independent VDR reporter activity and the induction of CYP24A1 above controls. These results demonstrate how alternative splicing can re-program NR gene function, highlighting novel mechanisms of toxicity and new opportunities for the use of splice-switching oligonucleotides (SSO) in precision medicine.
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Affiliation(s)
- Andrew J Annalora
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture & Life Sciences Building, Corvallis, OR 97331; USA.
| | - Marija Jozic
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture & Life Sciences Building, Corvallis, OR 97331; USA
| | - Craig B Marcus
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture & Life Sciences Building, Corvallis, OR 97331; USA
| | - Patrick L Iversen
- Department of Environmental and Molecular Toxicology, Oregon State University, 1007 Agriculture & Life Sciences Building, Corvallis, OR 97331; USA; LS Pharma, 884 Park St., Lebanon, OR 97355; USA
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