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Gao H, Rocha KCE, Jin Z, Kumar D, Zhang D, Wang K, Das M, Farrell A, Truong T, Tekin Y, Jung HS, Kempf J, Webster NJG, Ying W. Restoring SRSF3 in Kupffer cells attenuates obesity-related insulin resistance. Hepatology 2024:01515467-990000000-00795. [PMID: 38456794 DOI: 10.1097/hep.0000000000000836] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 01/05/2024] [Indexed: 03/09/2024]
Abstract
BACKGROUND AND AIMS In obesity, depletion of KCs expressing CRIg (complement receptor of the Ig superfamily) leads to microbial DNA accumulation, which subsequently triggers tissue inflammation and insulin resistance. However, the mechanism underlying obesity-mediated changes in KC complement immune functions is largely unknown. APPROACH AND RESULTS Using KC-specific deactivated Cas9 transgenic mice treated with guide RNA, we assessed the effects of restoring CRIg or the serine/arginine-rich splicing factor 3 (SRSF3) abundance on KC functions and metabolic phenotypes in obese mice. The impacts of weight loss on KC responses were evaluated in a diet switch mouse model. The role of SRSF3 in regulating KC functions was also evaluated using KC-specific SRSF3 knockout mice. Here, we report that overexpression of CRIg in KCs of obese mice protects against bacterial DNA accumulation in metabolic tissues. Mechanistically, SRSF3 regulates CRIg expression, which is essential for maintaining the CRIg+ KC population. During obesity, SRSF3 expression decreases, but it is restored with weight loss through a diet switch, normalizing CRIg+ KCs. KC SRSF3 is also repressed in obese human livers. Lack of SRSF3 in KCs in lean and obese mice decreases their CRIg+ population, impairing metabolic parameters. During the diet switch, the benefits of weight loss are compromised due to SRSF3 deficiency. Conversely, SRSF3 overexpression in obese mice preserves CRIg+ KCs and improves metabolic responses. CONCLUSIONS Restoring SRSF3 abundance in KCs offers a strategy against obesity-associated tissue inflammation and insulin resistance by preventing bacterial DNA accumulation.
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Affiliation(s)
- Hong Gao
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
| | - Karina C E Rocha
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
| | - Zhongmou Jin
- Division of Biological Sciences, University of California, San Diego, California, USA
| | - Deepak Kumar
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
- VA San Diego Healthcare System, San Diego, California, USA
| | - Dinghong Zhang
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
| | - Ke Wang
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
| | - Manasi Das
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
- VA San Diego Healthcare System, San Diego, California, USA
| | - Andrea Farrell
- Division of Biological Sciences, University of California, San Diego, California, USA
| | - Tyler Truong
- Division of Biological Sciences, University of California, San Diego, California, USA
| | - Yasemin Tekin
- Division of Biological Sciences, University of California, San Diego, California, USA
| | - Hyun Suh Jung
- Division of Biological Sciences, University of California, San Diego, California, USA
| | - Julia Kempf
- Division of Biological Sciences, University of California, San Diego, California, USA
| | - Nicholas J G Webster
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
- VA San Diego Healthcare System, San Diego, California, USA
- Moores Cancer Center, University of California, La Jolla, San Diego, California, USA
| | - Wei Ying
- Department of Medicine, Division of Endocrinology & Metabolism, University of California, San Diego, La Jolla, California, USA
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Over-Expression of Two Different Isoforms of Cattle TUSC5 Showed Opposite Effects on Adipogenesis. Genes (Basel) 2022; 13:genes13081444. [PMID: 36011355 PMCID: PMC9408160 DOI: 10.3390/genes13081444] [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: 07/10/2022] [Revised: 08/03/2022] [Accepted: 08/09/2022] [Indexed: 11/16/2022] Open
Abstract
(1) Background: Adipogenesis is an important issue in human health and livestock meat quality that has received widespread attention and extensive study. However, alternative splicing events may generate multiple isoforms with different functions. This will lead to known knowledge being far more complex than before. (2) Methods: We studied the effects of two different TUSC5 isoforms (TUSC5A and TUSC5B) in cattle on adipogenesis by constructing over-expression cell models and RNA-sequencing methods. (3) Results: We discovered that over-expression of TUSC5A promotes the process of adipogenesis while over-expression of TUSC5B suppresses it. Eight important genes (PPARG, ACC1, FASN, SCD1, LPL, FABP4, GPDH, and GLUT4) during adipogenesis were significantly promoted (student’s t-test, p < 0.05) by TUSC5A and suppressed by TUSC5B both before and after cell differentiation. By performing a comprehensive analysis using a RNA-seq strategy, we found that both up-regulated differentially expressed genes (DEGs, |log2FoldChange| ≥ 1, p ≤ 0.05) of TUSC5A and down-regulated DEGs of TUSC5B were significantly enriched in the adipogenesis related GO terms, and the PPAR signaling pathway may play important role in those differences. (4) Conclusions: Our study proved that over-expression of two TUSC5 isoforms would regulate adipogenesis in the opposite direction. It is important to understand the function of the TUSC5 gene correctly.
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Leclair NK, Brugiolo M, Urbanski L, Lawson SC, Thakar K, Yurieva M, George J, Hinson JT, Cheng A, Graveley BR, Anczuków O. Poison Exon Splicing Regulates a Coordinated Network of SR Protein Expression during Differentiation and Tumorigenesis. Mol Cell 2020; 80:648-665.e9. [PMID: 33176162 PMCID: PMC7680420 DOI: 10.1016/j.molcel.2020.10.019] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/07/2020] [Accepted: 10/12/2020] [Indexed: 12/18/2022]
Abstract
The RNA isoform repertoire is regulated by splicing factor (SF) expression, and alterations in SF levels are associated with disease. SFs contain ultraconserved poison exon (PE) sequences that exhibit greater identity across species than nearby coding exons, but their physiological role and molecular regulation is incompletely understood. We show that PEs in serine-arginine-rich (SR) proteins, a family of 14 essential SFs, are differentially spliced during induced pluripotent stem cell (iPSC) differentiation and in tumors versus normal tissues. We uncover an extensive cross-regulatory network of SR proteins controlling their expression via alternative splicing coupled to nonsense-mediated decay. We define sequences that regulate PE inclusion and protein expression of the oncogenic SF TRA2β using an RNA-targeting CRISPR screen. We demonstrate location dependency of RS domain activity on regulation of TRA2β-PE using CRISPR artificial SFs. Finally, we develop splice-switching antisense oligonucleotides to reverse the increased skipping of TRA2β-PE detected in breast tumors, altering breast cancer cell viability, proliferation, and migration.
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Affiliation(s)
- Nathan K Leclair
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Graduate Program in Genetics and Development, UConn Health, Farmington, CT, USA
| | - Mattia Brugiolo
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Laura Urbanski
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Graduate Program in Genetics and Development, UConn Health, Farmington, CT, USA
| | - Shane C Lawson
- Graduate Program in Genetics and Development, UConn Health, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA
| | - Ketan Thakar
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Marina Yurieva
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA
| | - Joshy George
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA
| | - John Travis Hinson
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA
| | - Albert Cheng
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA
| | - Brenton R Graveley
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA
| | - Olga Anczuków
- The Jackson Laboratory for Genomic Medicine, Farmington, CT, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT, USA; Institute for Systems Genomics, UConn Health, Farmington, CT, USA.
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Jeffery N, Richardson S, Chambers D, Morgan NG, Harries LW. Cellular stressors may alter islet hormone cell proportions by moderation of alternative splicing patterns. Hum Mol Genet 2020; 28:2763-2774. [PMID: 31098640 PMCID: PMC6687954 DOI: 10.1093/hmg/ddz094] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Revised: 04/26/2019] [Accepted: 04/27/2019] [Indexed: 01/12/2023] Open
Abstract
Changes to islet cell identity in response to type 2 diabetes (T2D) have been reported in rodent models, but are less well characterized in humans. We assessed the effects of aspects of the diabetic microenvironment on hormone staining, total gene expression, splicing regulation and the alternative splicing patterns of key genes in EndoC-βH1 human beta cells. Genes encoding islet hormones [somatostatin (SST), insulin (INS), Glucagon (GCG)], differentiation markers [Forkhead box O1 (FOXO1), Paired box 6, SRY box 9, NK6 Homeobox 1, NK6 Homeobox 2] and cell stress markers (DNA damage inducible transcript 3, FOXO1) were dysregulated in stressed EndoC-βH1 cells, as were some serine arginine rich splicing factor splicing activator and heterogeneous ribonucleoprotein particle inhibitor genes. Whole transcriptome analysis of primary T2D islets and matched controls demonstrated dysregulated splicing for ~25% of splicing events, of which genes themselves involved in messenger ribonucleic acid processing and regulation of gene expression comprised the largest group. Approximately 5% of EndoC-βH1 cells exposed to these factors gained SST positivity in vitro. An increased area of SST staining was also observed ex vivo in pancreas sections recovered at autopsy from donors with type 1 diabetes (T1D) or T2D (9.3% for T1D and 3% for T2D, respectively compared with 1% in controls). Removal of the stressful stimulus or treatment with the AKT Serine/Threonine kinase inhibitor SH-6 restored splicing factor expression and reversed both hormone staining effects and patterns of gene expression. This suggests that reversible changes in hormone expression may occur during exposure to diabetomimetic cellular stressors, which may be mediated by changes in splicing regulation.
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Affiliation(s)
- Nicola Jeffery
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW, UK
| | - Sarah Richardson
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW, UK
| | - David Chambers
- Wolfson Centre for Age-Related Diseases, King's College London, London WC2R 2LS, UK
| | - Noel G Morgan
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW, UK
| | - Lorna W Harries
- Institute of Biomedical and Clinical Sciences, University of Exeter Medical School, Barrack Road, Exeter EX2 5DW, UK
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Yu JW, Yuan HW, Bao LD, Si LG. Interaction between piperine and genes associated with sciatica and its mechanism based on molecular docking technology and network pharmacology. Mol Divers 2020; 25:233-248. [PMID: 32130644 PMCID: PMC7870775 DOI: 10.1007/s11030-020-10055-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 02/17/2020] [Indexed: 12/15/2022]
Abstract
Abstract Piperine is the main active component of Piper longum L., which is also the main component of anti-sciatica Mongolian medicine Naru Sanwei pill. It has many pharmacological activities such as anti-inflammatory and immune regulation.
This paper aims to preliminarily explore the potential mechanism of piperine in the treatment of sciatica through network pharmacology and molecular docking. TCMSP, ETCM database and literature mining were used to collect the active compounds of Piper longum L. Swiss TargetPrediction and SuperPred server were used to find the targets of compounds. At the same time, CTD database was used to collect the targets of sciatica. Then the above targets were compared and analyzed to select the targets of anti-sciatica in Piper longum L. The Go (gene ontology) annotation and KEGG pathway of the targets were enriched and analyzed by Metascape database platform. The molecular docking between the effective components and the targets was verified by Autodock. After that, the sciatica model of rats was established and treated with piperine. The expression level of inflammatory factors and proteins in the serum and tissues of rat sciatic nerve were detected by ELISA and Western blot. HE staining and immunohistochemistry were carried out on the sciatica tissues of rats. The results showed that Piper longum L. can regulate the development of sciatica and affect the expressions of PPARG and NF-kB1 through its active ingredient piperine, and there is endogenous interaction between PPARG and NF-kB1. Graphic abstract ![]()
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Affiliation(s)
- Jiu-Wang Yu
- Department of Pharmacy, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, 010059, Inner Mongolia, People's Republic of China
| | - Hong-Wei Yuan
- Department of Pathology, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, 010059, Inner Mongolia, People's Republic of China
| | - Li-Dao Bao
- Department of Pharmacy, Affiliated Hospital of Inner Mongolia Medical University, Hohhot, 010059, Inner Mongolia, People's Republic of China.
| | - Leng-Ge Si
- Mongolia Medical School, Inner Mongolia Medical University, Hohhot, 010110, Inner Mongolia, People's Republic of China
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Minami S, Yokota N, Kawahara H. BAG6 contributes to glucose uptake by supporting the cell surface translocation of the glucose transporter GLUT4. Biol Open 2020; 9:bio.047324. [PMID: 31911483 PMCID: PMC6994957 DOI: 10.1242/bio.047324] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Defective translocation of glucose transporter 4 (GLUT4) to the cell surface is a key feature of insulin resistance in type 2 diabetes. Therefore, elucidating the mechanism of GLUT4 translocation is of primary importance. The mammalian Bag6/Bat3 gene has been suggested to be linked with potential obesity- and diabetes-associated loci, while its function in the control of glucose incorporation into the cytoplasm has not been investigated. In this study, we established a series of cell lines that stably expressed GLUT4 with three tandem repeats of the antigenic peptide inserted into its 1st extracellular loop. With these cell lines, we found that the depletion of endogenous BAG6 downregulated the cell surface expression of GLUT4, concomitant with the reduced incorporation of a glucose analog into the cells. Defective intracellular translocation of GLUT4 in BAG6-depleted cells is similar to the case observed for the depletion of Rab8a, an essential regulator of insulin-stimulated GLUT4 translocation. In addition, we observed that the assembly of syntaxin 6 into the endoplasmic reticulum membrane was slightly disturbed under BAG6 depletion. Given that Rab8a and syntaxin 6 are critical for GLUT4 translocation, we suggest that BAG6 may play multiple roles in the trafficking of glucose transporters to the cell surface. This article has an associated First Person interview with the first author of the paper. Summary: BAG6 is critical for the insulin-stimulated translocation of GLUT4 from its peri-nuclear storage compartments to the cell surface.
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Affiliation(s)
- Setsuya Minami
- Laboratory of Cell Biology and Biochemistry, Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan
| | - Naoto Yokota
- Laboratory of Cell Biology and Biochemistry, Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan
| | - Hiroyuki Kawahara
- Laboratory of Cell Biology and Biochemistry, Department of Biological Sciences, Tokyo Metropolitan University, Tokyo 192-0397, Japan
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7
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Patent highlights June-July 2018. Pharm Pat Anal 2019; 7:241-248. [PMID: 30632451 DOI: 10.4155/ppa-2018-0029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
A snapshot of noteworthy recent developments in the patent literature of relevance to pharmaceutical and medical research and development.
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8
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Alternative mRNA Splicing in the Pathogenesis of Obesity. Int J Mol Sci 2018; 19:ijms19020632. [PMID: 29473878 PMCID: PMC5855854 DOI: 10.3390/ijms19020632] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2018] [Revised: 02/21/2018] [Accepted: 02/21/2018] [Indexed: 12/22/2022] Open
Abstract
Alternative mRNA splicing is an important mechanism in expansion of proteome diversity by production of multiple protein isoforms. However, emerging evidence indicates that only a limited number of annotated protein isoforms by alternative splicing are detected, and the coding sequence of alternative splice variants usually is only slightly different from that of the canonical sequence. Nevertheless, mis-splicing is associated with a large array of human diseases. Previous reviews mainly focused on hereditary and somatic mutations in cis-acting RNA sequence elements and trans-acting splicing factors. The importance of environmental perturbations contributed to mis-splicing is not assessed. As significant changes in exon skipping and splicing factors expression levels are observed with diet-induced obesity, this review focuses on several well-known alternatively spliced metabolic factors and discusses recent advances in the regulation of the expressions of splice variants under the pathophysiological conditions of obesity. The potential of targeting the alternative mRNA mis-splicing for obesity-associated diseases therapies will also be discussed.
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Carayol J, Chabert C, Di Cara A, Armenise C, Lefebvre G, Langin D, Viguerie N, Metairon S, Saris WHM, Astrup A, Descombes P, Valsesia A, Hager J. Protein quantitative trait locus study in obesity during weight-loss identifies a leptin regulator. Nat Commun 2017; 8:2084. [PMID: 29234017 PMCID: PMC5727191 DOI: 10.1038/s41467-017-02182-z] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 11/10/2017] [Indexed: 12/12/2022] Open
Abstract
Thousands of genetic variants have been associated with complex traits through genome-wide association studies. However, the functional variants or mechanistic consequences remain elusive. Intermediate traits such as gene expression or protein levels are good proxies of the metabolic state of an organism. Proteome analysis especially can provide new insights into the molecular mechanisms of complex traits like obesity. The role of genetic variation in determining protein level variation has not been assessed in obesity. To address this, we design a large-scale protein quantitative trait locus (pQTL) analysis based on a set of 1129 proteins from 494 obese subjects before and after a weight loss intervention. This reveals 55 BMI-associated cis-pQTLs and trans-pQTLs at baseline and 3 trans-pQTLs after the intervention. We provide evidence for distinct genetic mechanisms regulating BMI-associated proteins before and after weight loss. Finally, by functional analysis, we identify and validate FAM46A as a trans regulator for leptin. Although many genetic variants are known for obesity, their function remains largely unknown. Here, in a weight-loss intervention cohort, the authors identify protein quantitative trait loci associated with BMI at baseline and after weight loss and find FAM46A to be a regulator of leptin in adipocytes.
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Affiliation(s)
- Jérôme Carayol
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland.
| | - Christian Chabert
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland
| | | | | | - Gregory Lefebvre
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland
| | - Dominique Langin
- INSERM UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, University of Toulouse, 1 avenue Jean Poulhès BP 84225, 31432, Toulouse, France
| | - Nathalie Viguerie
- INSERM UMR1048, Obesity Research Laboratory, Institute of Metabolic and Cardiovascular Diseases, University of Toulouse, 1 avenue Jean Poulhès BP 84225, 31432, Toulouse, France
| | - Sylviane Metairon
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland
| | - Wim H M Saris
- Department of Human Biology, NUTRIM, School of Nutrition and Translational Research in Metabolism, Maastricht University Medical Centre, PO Box 616, 6200 MD, Maastricht, The Netherlands
| | - Arne Astrup
- Department of Nutrition, Exercise and Sports, Faculty of Science, University of Copenhagen, Nørre Alle 51, DK-2200, Copenhagen N, Denmark
| | - Patrick Descombes
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland
| | - Armand Valsesia
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland
| | - Jörg Hager
- Nestlé Institute of Health Sciences, EPFL Innovation Park, 1015, Lausanne, Switzerland
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Dlamini Z, Mokoena F, Hull R. Abnormalities in alternative splicing in diabetes: therapeutic targets. J Mol Endocrinol 2017; 59:R93-R107. [PMID: 28716821 DOI: 10.1530/jme-17-0049] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 05/30/2017] [Indexed: 12/19/2022]
Abstract
Diabetes mellitus (DM) is a non-communicable, metabolic disorder that affects 416 million individuals worldwide. Type 2 diabetes contributes to a vast 85-90% of the diabetes incidences while 10-15% of patients suffer from type 1 diabetes. These two predominant forms of DM cause a significant loss of functional pancreatic β-cell mass causing different degrees of insulin deficiency, most likely, due to increased β-cell apoptosis. Treatment options involve the use of insulin sensitisers, α-glucosidase inhibitors, and β-cell secretagogues which are often expensive, limited in efficacy and carry detrimental adverse effects. Cost-effective options for treatment exists in the form of herbal drugs, however, scientific validations of these widely used medicinal plants are still underway. Alternative splicing (AS) is a co-ordinated post-transcriptional process in which a single gene generates multiple mRNA transcripts which results in increased amounts of functionally different protein isoforms and in some cases aberrant splicing leads to metabolic disease. In this review, we explore the association of AS with metabolic alterations in DM and the biological significance of the abnormal splicing of some pathogenic diabetes-related genes. An understanding of the molecular mechanism behind abnormally spliced transcripts will aid in the development of new diagnostic, prognostic and therapeutic tools.
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Affiliation(s)
- Zodwa Dlamini
- ResearchInnovation & Engagements Portfolio, Mangosuthu University of Technology, Durban, South Africa
| | - Fortunate Mokoena
- ResearchInnovation & Engagements Portfolio, Mangosuthu University of Technology, Durban, South Africa
| | - Rodney Hull
- ResearchInnovation & Engagements Portfolio, Mangosuthu University of Technology, Durban, South Africa
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Intersections of post-transcriptional gene regulatory mechanisms with intermediary metabolism. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2017; 1860:349-362. [PMID: 28088440 DOI: 10.1016/j.bbagrm.2017.01.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/09/2017] [Accepted: 01/09/2017] [Indexed: 12/16/2022]
Abstract
Intermediary metabolism studies have typically concentrated on four major regulatory mechanisms-substrate availability, allosteric enzyme regulation, post-translational enzyme modification, and regulated enzyme synthesis. Although transcriptional control has been a big focus, it is becoming increasingly evident that many post-transcriptional events are deeply embedded within the core regulatory circuits of enzyme synthesis/breakdown that maintain metabolic homeostasis. The prominent post-transcriptional mechanisms affecting intermediary metabolism include alternative pre-mRNA processing, mRNA stability and translation control, and the more recently discovered regulation by noncoding RNAs. In this review, we discuss the latest advances in our understanding of these diverse mechanisms at the cell-, tissue- and organismal-level. We also highlight the dynamics, complexity and non-linear nature of their regulatory roles in metabolic decision making, and deliberate some of the outstanding questions and challenges in this rapidly expanding field.
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