1
|
Goutzelas Y, Kontou P, Mamuris Z, Bagos P, Sarafidou T. Meta-analysis of gene expression data in adipose tissue reveals new obesity associated genes. Gene 2022; 818:146223. [PMID: 35063573 DOI: 10.1016/j.gene.2022.146223] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 11/28/2021] [Accepted: 01/13/2022] [Indexed: 01/16/2023]
Abstract
High-throughput transcriptomic and proteomic data like microarray data are deposited in public databases such as Gene Expression Omnibus (GEO). Omics data integration and processing from different and independent studies is achieved by using efficient and effective computational tools through meta-analysis. Meta-analysis is a statistical powerful tool combining data from numerous studies, minimizes bias and increases statistical power by increasing sample size compared to individual studies. Therefore, we performed a meta-analysis of gene expression data in adipose tissue to identify genes that are differentially expressed between obese and non-obese subjects as well as to detect gene expression signatures, pathways and networks associated with obesity. We identified 821 differentially expressed genes (DEGs) in adipose tissue of obese subjects compared to non-obese. A protein-protein interactions (PPIs) network was reconstructed consisting of 168 proteins. Functional enrichment analysis in the network revealed proteins involved in RNA and energy metabolism. The KEGG pathway analysis revealed 15 enriched pathway terms. Furthermore, multiple testing correction methods identified five statistically significant obesity associated genes (NDUFA12, SFI1, SSB, FAR2 and LACE1) that require further investigation.
Collapse
Affiliation(s)
- Yiannis Goutzelas
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Panagiota Kontou
- Department of Computer Science and Biomedical Informatics, University of Thessaly, Lamia, Greece
| | - Zissis Mamuris
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece
| | - Pantelis Bagos
- Department of Computer Science and Biomedical Informatics, University of Thessaly, Lamia, Greece
| | - Theologia Sarafidou
- Department of Biochemistry and Biotechnology, University of Thessaly, Larissa, Greece.
| |
Collapse
|
2
|
Abstract
Recent years have seen unprecedented activity in the development of RNA-silencing oligonucleotide therapeutics for metabolic diseases. Improved oligonucleotide design and optimization of synthetic nucleic acid chemistry, in combination with the development of highly selective and efficient conjugate delivery technology platforms, have established and validated oligonucleotides as a new class of drugs. To date, there are five marketed oligonucleotide therapies, with many more in clinical studies, for both rare and common liver-driven metabolic diseases. Here, we provide an overview of recent developments in the field of oligonucleotide therapeutics in metabolism, review past and current clinical trials, and discuss ongoing challenges and possible future developments.
Collapse
|
3
|
Romartinez-Alonso B, Agostini M, Jones H, McLellan J, Sood D, Tomkinson N, Marelli F, Gentile I, Visser WE, Schoenmakers E, Fairall L, Privalsky M, Moran C, Persani L, Chatterjee K, Schwabe J. Structure-guided approach to relieving transcriptional repression inResistance to Thyroid Hormone α. Mol Cell Biol 2021;:MCB0036321. [PMID: 34871063 DOI: 10.1128/MCB.00363-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mutations in thyroid hormone receptor α (TRα), a ligand-inducible transcription factor, cause Resistance to Thyroid Hormone α (RTHα). This disorder is characterised by tissue-specific hormone refractoriness and hypothyroidism, due to inhibition of target gene expression by mutant TRα-corepressor complexes. Using biophysical approaches, we show that RTHα-associated TRα mutants devoid of ligand-dependent transcription activation function, unexpectedly retain the ability to bind thyroid hormone. Visualisation of ligand (T3) within the crystal structure of a prototypic TRα mutant, validates this notion. This finding prompted synthesis of different thyroid hormone analogues, identifying a lead compound (ES08) which dissociates corepressor from mutant human TRα more efficaciously than T3. ES08 rescues developmental anomalies in a zebrafish model of RTHα and induces target gene expression in TRα mutation-containing cells from an RTHα patient, more effectively than T3. Our observations provide proof-of-principle for developing synthetic ligands that can relieve transcriptional repression by the mutant TRα-corepressor complex, for treatment of RTHα.
Collapse
|
4
|
Teng L, Feng YC, Guo ST, Wang PL, Qi TF, Yue YM, Wang SX, Zhang SN, Tang CX, La T, Zhang YY, Zhao XH, Gao JN, Wei LY, Zhang D, Wang JY, Shi Y, Liu XY, Li JM, Cao H, Liu T, Thorne RF, Jin L, Shao FM, Zhang XD. The pan-cancer lncRNA PLANE regulates an alternative splicing program to promote cancer pathogenesis. Nat Commun 2021; 12:3734. [PMID: 34145290 PMCID: PMC8213729 DOI: 10.1038/s41467-021-24099-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2020] [Accepted: 06/02/2021] [Indexed: 12/20/2022] Open
Abstract
Genomic amplification of the distal portion of chromosome 3q, which encodes a number of oncogenic proteins, is one of the most frequent chromosomal abnormalities in malignancy. Here we functionally characterise a non-protein product of the 3q region, the long noncoding RNA (lncRNA) PLANE, which is upregulated in diverse cancer types through copy number gain as well as E2F1-mediated transcriptional activation. PLANE forms an RNA-RNA duplex with the nuclear receptor co-repressor 2 (NCOR2) pre-mRNA at intron 45, binds to heterogeneous ribonucleoprotein M (hnRNPM) and facilitates the association of hnRNPM with the intron, thus leading to repression of the alternative splicing (AS) event generating NCOR2-202, a major protein-coding NCOR2 AS variant. This is, at least in part, responsible for PLANE-mediated promotion of cancer cell proliferation and tumorigenicity. These results uncover the function and regulation of PLANE and suggest that PLANE may constitute a therapeutic target in the pan-cancer context.
Collapse
Affiliation(s)
- Liu Teng
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Yu Chen Feng
- School of Medicine and Public Health, The University of Newcastle, Callaghan, NSW, Australia
| | - Su Tang Guo
- Department of Molecular Biology, Shanxi Cancer Hospital and Institute, Shanxi, China
| | - Pei Lin Wang
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Teng Fei Qi
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Yi Meng Yue
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Shi Xing Wang
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Sheng Nan Zhang
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Cai Xia Tang
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Ting La
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Yuan Yuan Zhang
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Xiao Hong Zhao
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Jin Nan Gao
- Department of Breast Surgery, Shanxi Bethune Hospital, Shanxi, China
| | - Li Yuan Wei
- Department of Breast Surgery, Shanxi Bethune Hospital, Shanxi, China
| | - Didi Zhang
- Orthopaedics Department, John Hunter Hospital, Hunter New England Health, New Lambton, NSW, Australia
| | - Jenny Y Wang
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, NSW, Australia
| | - Yujie Shi
- Department of Pathology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan, China
| | - Xiao Ying Liu
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Jin Ming Li
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
| | - Huixia Cao
- Department of Nephrology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan, China
| | - Tao Liu
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
- Children's Cancer Institute Australia for Medical Research, University of New South Wales, Sydney, NSW, Australia
| | - Rick F Thorne
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia
| | - Lei Jin
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China.
- School of Medicine and Public Health, The University of Newcastle, Callaghan, NSW, Australia.
| | - Feng-Min Shao
- Department of Nephrology, Henan Provincial People's Hospital, Zhengzhou University People's Hospital, Henan, China.
| | - Xu Dong Zhang
- Translational Research Institute, Henan Provincial People's Hospital and People's Hospital of Zhengzhou University, Academy of Medical Science, Zhengzhou University, Henan, China.
- School of Biomedical Sciences and Pharmacy, The University of Newcastle, Callaghan, NSW, Australia.
| |
Collapse
|
5
|
Chao Y, Jiang Y, Zhong M, Wei K, Hu C, Qin Y, Zuo Y, Yang L, Shen Z, Zou C. Regulatory roles and mechanisms of alternative RNA splicing in adipogenesis and human metabolic health. Cell Biosci 2021; 11:66. [PMID: 33795017 PMCID: PMC8017860 DOI: 10.1186/s13578-021-00581-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 03/24/2021] [Indexed: 12/15/2022] Open
Abstract
Alternative splicing (AS) regulates gene expression patterns at the post-transcriptional level and generates a striking expansion of coding capacities of genomes and cellular protein diversity. RNA splicing could undergo modulation and close interaction with genetic and epigenetic machinery. Notably, during the adipogenesis processes of white, brown and beige adipocytes, AS tightly interplays with the differentiation gene program networks. Here, we integrate the available findings on specific splicing events and distinct functions of different splicing regulators as examples to highlight the directive biological contribution of AS mechanism in adipogenesis and adipocyte biology. Furthermore, accumulating evidence has suggested that mutations and/or altered expression in splicing regulators and aberrant splicing alterations in the obesity-associated genes are often linked to humans’ diet-induced obesity and metabolic dysregulation phenotypes. Therefore, significant attempts have been finally made to overview novel detailed discussion on the prospects of splicing machinery with obesity and metabolic disorders to supply featured potential management mechanisms in clinical applicability for obesity treatment strategies.
Collapse
Affiliation(s)
- Yunqi Chao
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Yonghui Jiang
- Department of Genetics, Yale University School of Medicine, New Haven, CT, 06520, USA
| | - Mianling Zhong
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Kaiyan Wei
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Chenxi Hu
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Yifang Qin
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Yiming Zuo
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Lili Yang
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Zheng Shen
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China
| | - Chaochun Zou
- Department of Endocrinology, The Children's Hospital, School of Medicine, Zhejiang University, Hangzhou, 310052, Zhejiang, China.
| |
Collapse
|
6
|
Goodson ML, Knotts TA, Campbell EL, Snyder CA, Young BM, Privalsky ML. Specific ablation of the NCoR corepressor δ splice variant reveals alternative RNA splicing as a key regulator of hepatic metabolism. PLoS One 2020; 15:e0241238. [PMID: 33104749 PMCID: PMC7588069 DOI: 10.1371/journal.pone.0241238] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/10/2020] [Indexed: 12/15/2022] Open
Abstract
The NCoR corepressor plays critical roles in mediating transcriptional repression by both nuclear receptors and non-receptor transcription factors. Alternative mRNA splicing of NCoR produces a series of variants with differing molecular and biological properties. The NCoRω splice-variant inhibits adipogenesis whereas the NCoRδ splice-variant promotes it, and mice bearing a splice-specific knockout of NCoRω display enhanced hepatic steatosis and overall weight gain on a high fat diet as well as a greatly increased resistance to diet-induced glucose intolerance. We report here that the reciprocal NCoRδ splice-specific knock-out mice display the contrary phenotypes of reduced hepatic steatosis and reduced weight gain relative to the NCoRω-/- mice. The NCoRδ-/- mice also fail to demonstrate the strong resistance to diet-induced glucose intolerance exhibited by the NCoRω-/- animals. The NCoR δ and ω variants possess both unique and shared transcriptional targets, with expression of certain hepatic genes affected in opposite directions in the two mutants, others altered in one but not the other genotype, and yet others changed in parallel in both NCoRδ-/- and NCoRω-/- animals versus WT. Gene set expression analysis (GSEA) identified a series of lipid, carbohydrate, and amino acid metabolic pathways that are likely to contribute to their distinct steatosis and glucose tolerance phenotypes. We conclude that alternative-splicing of the NCoR corepressor plays a key role in the regulation of hepatic energy storage and utilization, with the NCoRδ and NCoRω variants exerting both opposing and shared functions in many aspects of this phenomenon and in the organism as a whole.
Collapse
Affiliation(s)
- Michael L. Goodson
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, Davis, California, United States of America
- * E-mail:
| | - Trina A. Knotts
- Department of Molecular Biosciences, School of Veterinary Medicine and Mouse Metabolic Phenotyping Center, Microbiome & Host Response Core, University of California at Davis, Davis, California, United States of America
| | - Elsie L. Campbell
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, Davis, California, United States of America
| | - Chelsea A. Snyder
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, Davis, California, United States of America
| | - Briana M. Young
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, Davis, California, United States of America
| | - Martin L. Privalsky
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, Davis, California, United States of America
| |
Collapse
|
7
|
Privalsky ML, Goodson ML. Evolution of NCoR-1 and NCoR-2 corepressor alternative mRNA splicing in placental mammals. BMC Res Notes 2019; 12:343. [PMID: 31208445 PMCID: PMC6580476 DOI: 10.1186/s13104-019-4384-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 06/11/2019] [Indexed: 11/10/2022] Open
Abstract
OBJECTIVE The NCoR-1 and NCoR-2 corepressors are products of an early gene duplication near the beginning of vertebrate evolution and play both overlapping and divergent roles in development and physiology. Alternative-splicing of NCoR-1 and NCoR-2 further customizes their functions. To better understand the evolutionary basis of this phenomenon we extended our prior study of NCoR-1 and NCoR-2 alternative-splicing to an expanded series of species. RESULTS Alternative-splicing of NCoR-2 was observed in all vertebrates examined whereas alternative-splicing of NCoR-1 was largely limited to placental mammals. Notably the most prominent of the NCoR-1 alternative-splicing events specific to the placental lineage, in exon 37 that plays a key role in murine metabolism, mimics in many features an analogous alternative-splicing event that appeared in NCoR-2 much earlier at the beginning of the vertebrate radiation. Detection of additional alternative-splicing events, at exons 28 in NCoR-1 or NCoR-2, was limited to the Rodentia or Primates examined, indicating both corepressor paralogs continued to acquire additional splice variations more recently and independently of one another. Our results suggest that the NCoR-1/NCoR-2 paralogs have been subject to a mix of shared and distinct selective pressures, resulting in the pattern of divergent and convergent alternative-splicing observed in extant species.
Collapse
Affiliation(s)
- Martin L Privalsky
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, Davis, CA, 95616, USA.
| | - Michael L Goodson
- Department of Anatomy, Physiology, and Cell Biology, College of Veterinary Medicine, University of California at Davis, Davis, CA, 95616, USA
| |
Collapse
|
8
|
Müller L, Hainberger D, Stolz V, Ellmeier W. NCOR1-a new player on the field of T cell development. J Leukoc Biol 2018; 104:1061-1068. [PMID: 30117609 DOI: 10.1002/jlb.1ri0418-168r] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Revised: 07/18/2018] [Accepted: 07/21/2018] [Indexed: 12/27/2022] Open
Abstract
Nuclear receptor corepressor 1 (NCOR1) is a transcriptional corepressor that links chromatin-modifying enzymes with gene-specific transcription factors. Although identified more than 20 years ago as a corepressor of nuclear receptors, the role of NCOR1 in T cells remained only poorly understood. However, recent studies indicate that the survival of developing thymocytes is regulated by NCOR1, revealing an essential role for NCOR1 in the T cell lineage. In this review, we will briefly summarize basic facts about NCOR1 structure and functions. We will further summarize studies demonstrating an essential role for NCOR1 in controlling positive and negative selection of thymocytes during T cell development. Finally, we will discuss similarities and differences between the phenotypes of mice with a T cell-specific deletion of NCOR1 or histone deacetylase 3 (HDAC3), because HDAC3 is the predominant member of the HDAC family that interacts with NCOR1 corepressor complexes. With this review we aim to introduce NCOR1 as a new player in the team of transcriptional coregulators that control T cell development and thus the generation of the peripheral T cell pool.
Collapse
Affiliation(s)
- Lena Müller
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Daniela Hainberger
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Valentina Stolz
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Wilfried Ellmeier
- Division of Immunobiology, Institute of Immunology, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| |
Collapse
|
9
|
Wong CM, Xu L, Yau MY. Alternative mRNA Splicing in the Pathogenesis of Obesity. Int J Mol Sci 2018; 19:E632. [PMID: 29473878 DOI: 10.3390/ijms19020632] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [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.
Collapse
|
10
|
Wang J, Rajbhandari P, Damianov A, Han A, Sallam T, Waki H, Villanueva CJ, Lee SD, Nielsen R, Mandrup S, Reue K, Young SG, Whitelegge J, Saez E, Black DL, Tontonoz P. RNA-binding protein PSPC1 promotes the differentiation-dependent nuclear export of adipocyte RNAs. J Clin Invest 2017; 127:987-1004. [PMID: 28192372 DOI: 10.1172/jci89484] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 12/15/2016] [Indexed: 12/14/2022] Open
Abstract
A highly orchestrated gene expression program establishes the properties that define mature adipocytes, but the contribution of posttranscriptional factors to the adipocyte phenotype is poorly understood. Here we have shown that the RNA-binding protein PSPC1, a component of the paraspeckle complex, promotes adipogenesis in vitro and is important for mature adipocyte function in vivo. Cross-linking and immunoprecipitation followed by RNA sequencing revealed that PSPC1 binds to intronic and 3'-untranslated regions of a number of adipocyte RNAs, including the RNA encoding the transcriptional regulator EBF1. Purification of the paraspeckle complex from adipocytes further showed that PSPC1 associates with the RNA export factor DDX3X in a differentiation-dependent manner. Remarkably, PSPC1 relocates from the nucleus to the cytoplasm during differentiation, coinciding with enhanced export of adipogenic RNAs. Mice lacking PSPC1 in fat displayed reduced lipid storage and adipose tissue mass and were resistant to diet-induced obesity and insulin resistance due to a compensatory increase in energy expenditure. These findings highlight a role for PSPC1-dependent RNA maturation in the posttranscriptional control of adipose development and function.
Collapse
|
11
|
Privalsky ML, Snyder CA, Goodson ML. Corepressor diversification by alternative mRNA splicing is species specific. BMC Evol Biol 2016; 16:221. [PMID: 27756201 PMCID: PMC5069798 DOI: 10.1186/s12862-016-0781-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 09/30/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND SMRT and NCoR are corepressor paralogs that help mediate transcriptional repression by a variety of transcription factors, including the nuclear hormone receptors. The functions of both corepressors are extensively diversified in mice by alternative mRNA splicing, generating a series of protein variants that differ in different tissues and that exert different, even diametrically opposite, biochemical and biological effects from one another. RESULTS We report here that the alternative splicing previously reported for SMRT appears to be a relatively recent evolutionary phenomenon, with only one of these previously identified sites utilized in a teleost fish and a limited additional number of the additional known sites utilized in a bird, reptile, and marsupial. In contrast, extensive SMRT alternative splicing at these sites was detected among the placental mammals. The alternative splicing of NCoR previously identified in mice (and shown to regulate lipid and carbohydrate metabolism) is likely to have arisen separately and after that of SMRT, and includes an example of convergent evolution. CONCLUSIONS We propose that the functions of both SMRT and NCoR have been diversified by alternative splicing during evolution to allow customization for different purposes in different tissues and different species.
Collapse
Affiliation(s)
- Martin L Privalsky
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, One Shields Avenue, Davis, CA, 95616, USA.
| | - Chelsea A Snyder
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, One Shields Avenue, Davis, CA, 95616, USA
| | - Michael L Goodson
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, One Shields Avenue, Davis, CA, 95616, USA
| |
Collapse
|
12
|
Short S, Peterkin T, Guille M, Patient R, Sharpe C. Short linear motif acquisition, exon formation and alternative splicing determine a pathway to diversity for NCoR-family co-repressors. Open Biol 2016; 5:rsob.150063. [PMID: 26289800 PMCID: PMC4554918 DOI: 10.1098/rsob.150063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Vertebrate NCoR-family co-repressors play central roles in the timing of embryo and stem cell differentiation by repressing the activity of a range of transcription factors. They interact with nuclear receptors using short linear motifs (SLiMs) termed co-repressor for nuclear receptor (CoRNR) boxes. Here, we identify the pathway leading to increasing co-repressor diversity across the deuterostomes. The final complement of CoRNR boxes arose in an ancestral cephalochordate, and was encoded in one large exon; the urochordates and vertebrates then split this region between 10 and 12 exons. In Xenopus, alternative splicing is prevalent in NCoR2, but absent in NCoR1. We show for one NCoR1 exon that alternative splicing can be recovered by a single point mutation, suggesting NCoR1 lost the capacity for alternative splicing. Analyses in Xenopus and zebrafish identify that cellular context, rather than gene sequence, predominantly determines species differences in alternative splicing. We identify a pathway to diversity for the NCoR family beginning with the addition of a SLiM, followed by gene duplication, the generation of alternatively spliced isoforms and their differential deployment.
Collapse
Affiliation(s)
- Stephen Short
- Institute of Marine Sciences, School of Biological Science, University of Portsmouth, Portsmouth PO1 2DY, UK
| | - Tessa Peterkin
- The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Matthew Guille
- Institute of Biomolecular and Biomedical Science, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK European Xenopus Resource Centre, University of Portsmouth, St Michael's Building, Portsmouth PO1 2DT, UK
| | - Roger Patient
- The Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford OX3 9DS, UK
| | - Colin Sharpe
- Institute of Biomolecular and Biomedical Science, School of Biological Sciences, University of Portsmouth, Portsmouth PO1 2DY, UK European Xenopus Resource Centre, University of Portsmouth, St Michael's Building, Portsmouth PO1 2DT, UK
| |
Collapse
|
13
|
Abstract
Thyroid hormone (TH) controls a wide range of physiological processes through TH receptor (TR) isoforms. Classically, TRs are proposed to function as tri-iodothyronine (T3)-dependent transcription factors: on positively regulated target genes, unliganded TRs mediate transcriptional repression through recruitment of co-repressor complexes, while T3 binding leads to dismissal of co-repressors and recruitment of co-activators to activate transcription. Co-repressors and co-activators were proposed to play opposite roles in the regulation of negative T3 target genes and hypothalamic-pituitary-thyroid axis, but exact mechanisms of the negative regulation by TH have remained elusive. Important insights into the roles of co-repressors and co-activators in different physiological processes have been obtained using animal models with disrupted co-regulator function. At the same time, recent studies interrogating genome-wide TR binding have generated compelling new data regarding effects of T3, local chromatin structure, and specific response element configuration on TR recruitment and function leading to the proposal of new models of transcriptional regulation by TRs. This review discusses data obtained in various mouse models with manipulated function of nuclear receptor co-repressor (NCoR or NCOR1) and silencing mediator of retinoic acid receptor and thyroid hormone receptor (SMRT or NCOR2), and family of steroid receptor co-activators (SRCs also known as NCOAs) in the context of TH action, as well as insights into the function of co-regulators that may emerge from the genome-wide TR recruitment analysis.
Collapse
Affiliation(s)
- Inna Astapova
- Division of Endocrinology, Diabetes and MetabolismBeth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
14
|
Abstract
Nuclear receptors (NR) act as an integrated conduit for environmental and hormonal signals to govern genomic responses, which relate to cell fate decisions. We review how their integrated actions with each other, shared co-factors and other transcription factors are disrupted in cancer. Steroid hormone nuclear receptors are oncogenic drivers in breast and prostate cancer and blockade of signaling is a major therapeutic goal. By contrast to blockade of receptors, in other cancers enhanced receptor function is attractive, as illustrated initially with targeting of retinoic acid receptors in leukemia. In the post-genomic era large consortia, such as The Cancer Genome Atlas, have developed a remarkable volume of genomic data with which to examine multiple aspects of nuclear receptor status in a pan-cancer manner. Therefore to extend the review of NR function we have also undertaken bioinformatics analyses of NR expression in over 3000 tumors, spread across six different tumor types (bladder, breast, colon, head and neck, liver and prostate). Specifically, to ask how the NR expression was distorted (altered expression, mutation and CNV) we have applied bootstrapping approaches to simulate data for comparison, and also compared these NR findings to 12 other transcription factor families. Nuclear receptors were uniquely and uniformly downregulated across all six tumor types, more than predicted by chance. These approaches also revealed that each tumor type had a specific NR expression profile but these were most similar between breast and prostate cancer. Some NRs were down-regulated in at least five tumor types (e.g. NR3C2/MR and NR5A2/LRH-1)) whereas others were uniquely down-regulated in one tumor (e.g. NR1B3/RARG). The downregulation was not driven by copy number variation or mutation and epigenetic mechanisms maybe responsible for the altered nuclear receptor expression.
Collapse
Affiliation(s)
- Mark D Long
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| | - Moray J Campbell
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| |
Collapse
|
15
|
Stadhouders R, Cico A, Stephen T, Thongjuea S, Kolovos P, Baymaz HI, Yu X, Demmers J, Bezstarosti K, Maas A, Barroca V, Kockx C, Ozgur Z, van Ijcken W, Arcangeli ML, Andrieu-Soler C, Lenhard B, Grosveld F, Soler E. Control of developmentally primed erythroid genes by combinatorial co-repressor actions. Nat Commun 2015; 6:8893. [PMID: 26593974 PMCID: PMC4673834 DOI: 10.1038/ncomms9893] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2015] [Accepted: 10/14/2015] [Indexed: 12/21/2022] Open
Abstract
How transcription factors (TFs) cooperate within large protein complexes to allow rapid modulation of gene expression during development is still largely unknown. Here we show that the key haematopoietic LIM-domain-binding protein-1 (LDB1) TF complex contains several activator and repressor components that together maintain an erythroid-specific gene expression programme primed for rapid activation until differentiation is induced. A combination of proteomics, functional genomics and in vivo studies presented here identifies known and novel co-repressors, most notably the ETO2 and IRF2BP2 proteins, involved in maintaining this primed state. The ETO2–IRF2BP2 axis, interacting with the NCOR1/SMRT co-repressor complex, suppresses the expression of the vast majority of archetypical erythroid genes and pathways until its decommissioning at the onset of terminal erythroid differentiation. Our experiments demonstrate that multimeric regulatory complexes feature a dynamic interplay between activating and repressing components that determines lineage-specific gene expression and cellular differentiation. Conserved sets of transcription factors (TFs) regulate hematopoiesis. Here, Stadhouders et al. show that IRF2BP2 is a component of the LDB1 TF complex and together with its co-repressor ETO2, enhances transcriptional repression, which plays a crucial role at the erythroid progenitor stage.
Collapse
Affiliation(s)
- Ralph Stadhouders
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Alba Cico
- Inserm UMR967, CEA/DSV/iRCM, Laboratory of Molecular Hematopoiesis, Université Paris-Saclay, 92265 Fontenay-aux-Roses, France
| | - Tharshana Stephen
- Inserm UMR967, CEA/DSV/iRCM, Laboratory of Molecular Hematopoiesis, Université Paris-Saclay, 92265 Fontenay-aux-Roses, France
| | - Supat Thongjuea
- Computational Biology Unit, Bergen Center for Computational Science, N-5008 Bergen, Norway.,MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Petros Kolovos
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - H Irem Baymaz
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Xiao Yu
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Jeroen Demmers
- Department of Proteomics, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Karel Bezstarosti
- Department of Proteomics, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Alex Maas
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Vilma Barroca
- CEA/DSV/iRCM/SCSR, Université Paris-Saclay, 92265 Fontenay-aux-Roses, France
| | - Christel Kockx
- Center for Biomics, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Zeliha Ozgur
- Center for Biomics, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Wilfred van Ijcken
- Center for Biomics, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Marie-Laure Arcangeli
- Inserm UMR967, CEA/DSV/iRCM, Laboratory of Hematopoietic and Leukemic Stem cells, Université Paris-Saclay, 92265 Fontenay-aux-Roses, France
| | - Charlotte Andrieu-Soler
- Inserm UMR967, CEA/DSV/iRCM, Laboratory of Molecular Hematopoiesis, Université Paris-Saclay, 92265 Fontenay-aux-Roses, France
| | - Boris Lenhard
- Department of Molecular Sciences, Faculty of Medicine, MRC Clinical Sciences Centre, Institute of Clinical Sciences, Imperial College London, London W12 0NN, UK
| | - Frank Grosveld
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands.,Cancer Genomics Center, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands
| | - Eric Soler
- Department of Cell Biology, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands.,Inserm UMR967, CEA/DSV/iRCM, Laboratory of Molecular Hematopoiesis, Université Paris-Saclay, 92265 Fontenay-aux-Roses, France.,Cancer Genomics Center, Erasmus Medical Center, 3015CN Rotterdam, The Netherlands.,Laboratory of Excellence GR-Ex, 75015 Paris, France
| |
Collapse
|
16
|
Snyder CA, Goodson ML, Schroeder AC, Privalsky ML. Regulation of corepressor alternative mRNA splicing by hormonal and metabolic signaling. Mol Cell Endocrinol 2015; 413:228-35. [PMID: 26166430 PMCID: PMC4556269 DOI: 10.1016/j.mce.2015.06.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 06/24/2015] [Accepted: 06/29/2015] [Indexed: 12/14/2022]
Abstract
Alternative mRNA splicing diversifies the products encoded by the NCoR and SMRT corepressor loci. There is a programmed alteration in NCoR mRNA splicing during adipocyte differentiation from an NCoRω isoform, which contains three nuclear receptor interaction domains, to an NCoRδ isoform that contains two nuclear receptor interaction domains. This alternative mRNA splicing of NCoR has profound effects on adiposity and on diabetes in mouse models. We report here that dexamethasone, a powerful regulator of metabolism and of adipocyte differentiation, confers this change in NCoR mRNA splicing in cultured adipocytes. We also demonstrate that changes in dietary components can consistently, if moderately, modulate the total transcript levels and the mRNA splicing of NCoR and SMRT in both cultured cells and intact mice. This ability of alternative corepressor mRNA splicing to respond to nutritional changes confirms its importance in regulating glucose and lipid metabolism, and its promise as a therapeutic candidate for metabolic disorders such as type 2 diabetes.
Collapse
Affiliation(s)
- Chelsea A Snyder
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, USA.
| | - Michael L Goodson
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, USA.
| | - Amy C Schroeder
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, USA.
| | - Martin L Privalsky
- Department of Microbiology and Molecular Genetics, College of Biological Sciences, University of California at Davis, USA.
| |
Collapse
|
17
|
Long MD, van den Berg PR, Russell JL, Singh PK, Battaglia S, Campbell MJ. Integrative genomic analysis in K562 chronic myelogenous leukemia cells reveals that proximal NCOR1 binding positively regulates genes that govern erythroid differentiation and Imatinib sensitivity. Nucleic Acids Res 2015; 43:7330-48. [PMID: 26117541 PMCID: PMC4551916 DOI: 10.1093/nar/gkv642] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Accepted: 06/10/2015] [Indexed: 01/05/2023] Open
Abstract
To define the functions of NCOR1 we developed an integrative analysis that combined ENCODE and NCI-60 data, followed by in vitro validation. NCOR1 and H3K9me3 ChIP-Seq, FAIRE-seq and DNA CpG methylation interactions were related to gene expression using bootstrapping approaches. Most NCOR1 combinations (24/44) were associated with significantly elevated level expression of protein coding genes and only very few combinations related to gene repression. DAVID's biological process annotation revealed that elevated gene expression was uniquely associated with acetylation and ETS binding. A matrix of gene and drug interactions built on NCI-60 data identified that Imatinib significantly targeted the NCOR1 governed transcriptome. Stable knockdown of NCOR1 in K562 cells slowed growth and significantly repressed genes associated with NCOR1 cistrome, again, with the GO terms acetylation and ETS binding, and significantly dampened sensitivity to Imatinib-induced erythroid differentiation. Mining public microarray data revealed that NCOR1-targeted genes were significantly enriched in Imatinib response gene signatures in cell lines and chronic myelogenous leukemia (CML) patients. These approaches integrated cistrome, transcriptome and drug sensitivity relationships to reveal that NCOR1 function is surprisingly most associated with elevated gene expression, and that these targets, both in CML cell lines and patients, associate with sensitivity to Imatinib.
Collapse
Affiliation(s)
- Mark D Long
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| | - Patrick R van den Berg
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| | - James L Russell
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| | - Prashant K Singh
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| | - Sebastiano Battaglia
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| | - Moray J Campbell
- Department of Pharmacology and Therapeutics, Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, NY 14263, USA
| |
Collapse
|
18
|
Abstract
In recent years white adipose tissue inflammation has been recognized to be associated with obesity. Adipocytes and adipose tissue associated macrophages (ATMs) secrete bioactive molecules, including adipokines, chemokines/cytokines and free fatty acids that modulate the development of low-grade inflammation and insulin resistance responsible for obesity-related metabolic and cardiovascular diseases. Nuclear receptors, notably peroxisome-proliferator-activated receptors, are sensors of dietary lipids and control transcriptional programs of key metabolic and inflammatory pathways in adipocytes and macrophages. This review focuses on mechanisms by which nuclear receptors maintain white adipose tissue homeostasis. The identification of ATMs as active players in the initiation of chronic inflammation and the links between inflammatory signaling and metabolic dysfunction will be presented, followed by discussion of recent evidence for nuclear receptors in ATM function, with an emphasis on the paracrine interaction between adipocytes and ATMs.
Collapse
|
19
|
Goodson ML, Young BM, Snyder CA, Schroeder AC, Privalsky ML. Alteration of NCoR corepressor splicing in mice causes increased body weight and hepatosteatosis without glucose intolerance. Mol Cell Biol 2014; 34:4104-14. [PMID: 25182530 DOI: 10.1128/MCB.00554-14] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Alternative mRNA splicing is an important means of diversifying function in higher eukaryotes. Notably, both NCoR and SMRT corepressors are subject to alternative mRNA splicing, yielding a series of distinct corepressor variants with highly divergent functions. Normal adipogenesis is associated with a switch in corepressor splicing from NCoRω to NCoRδ, which appears to help regulate this differentiation process. We report here that mimicking this development switch in mice by a splice-specific whole-animal ablation of NCoRω is very different from a whole-animal or tissue-specific total NCoR knockout and produces significantly enhanced weight gain on a high-fat diet. Surprisingly, NCoRω(-/-) mice are protected against diet-induced glucose intolerance despite enhanced adiposity and the presence of multiple additional, prodiabetic phenotypic changes. Our results indicate that the change in NCoR splicing during normal development both helps drive normal adipocyte differentiation and plays a key role in determining a metabolically appropriate storage of excess calories. We also conclude that whole-gene "knockouts" fail to reveal how important gene products are customized, tailored, and adapted through alternative mRNA splicing and thus do not reveal all the functions of the protein products of that gene.
Collapse
|
20
|
Du C, Ma X, Meruvu S, Hugendubler L, Mueller E. The adipogenic transcriptional cofactor ZNF638 interacts with splicing regulators and influences alternative splicing. J Lipid Res 2014; 55:1886-96. [PMID: 25024404 DOI: 10.1194/jlr.m047555] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Increasing evidence indicates that transcription and alternative splicing are coordinated processes; however, our knowledge of specific factors implicated in both functions during the process of adipocyte differentiation is limited. We have previously demonstrated that the zinc finger protein ZNF638 plays a role as a transcriptional coregulator of adipocyte differentiation via induction of PPARγ in cooperation with CCAAT/enhancer binding proteins (C/EBPs). Here we provide new evidence that ZNF638 is localized in nuclear bodies enriched with splicing factors, and through biochemical purification of ZNF638's interacting proteins in adipocytes and mass spectrometry analysis, we show that ZNF638 interacts with splicing regulators. Functional analysis of the effects of ectopic ZNF638 expression on a minigene reporter demonstrated that ZNF638 is sufficient to promote alternative splicing, a function enhanced through its recruitment to the minigene promoter at C/EBP responsive elements via C/EBP proteins. Structure-function analysis revealed that the arginine/serine-rich motif and the C-terminal zinc finger domain required for speckle localization are necessary for the adipocyte differentiation function of ZNF638 and for the regulation of the levels of alternatively spliced isoforms of lipin1 and nuclear receptor co-repressor 1. Overall, our data demonstrate that ZNF638 participates in splicing decisions and that it may control adipogenesis through regulation of the relative amounts of differentiation-specific isoforms.
Collapse
Affiliation(s)
- Chen Du
- Genetics of Development and Disease Branch of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Xinran Ma
- Genetics of Development and Disease Branch of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Sunitha Meruvu
- Genetics of Development and Disease Branch of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Lynne Hugendubler
- Genetics of Development and Disease Branch of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| | - Elisabetta Mueller
- Genetics of Development and Disease Branch of the National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892
| |
Collapse
|
21
|
Abstract
Thyroid hormone (TH) is required for normal development as well as regulating metabolism in the adult. The thyroid hormone receptor (TR) isoforms, α and β, are differentially expressed in tissues and have distinct roles in TH signaling. Local activation of thyroxine (T4), to the active form, triiodothyronine (T3), by 5'-deiodinase type 2 (D2) is a key mechanism of TH regulation of metabolism. D2 is expressed in the hypothalamus, white fat, brown adipose tissue (BAT), and skeletal muscle and is required for adaptive thermogenesis. The thyroid gland is regulated by thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH). In addition to TRH/TSH regulation by TH feedback, there is central modulation by nutritional signals, such as leptin, as well as peptides regulating appetite. The nutrient status of the cell provides feedback on TH signaling pathways through epigentic modification of histones. Integration of TH signaling with the adrenergic nervous system occurs peripherally, in liver, white fat, and BAT, but also centrally, in the hypothalamus. TR regulates cholesterol and carbohydrate metabolism through direct actions on gene expression as well as cross-talk with other nuclear receptors, including peroxisome proliferator-activated receptor (PPAR), liver X receptor (LXR), and bile acid signaling pathways. TH modulates hepatic insulin sensitivity, especially important for the suppression of hepatic gluconeogenesis. The role of TH in regulating metabolic pathways has led to several new therapeutic targets for metabolic disorders. Understanding the mechanisms and interactions of the various TH signaling pathways in metabolism will improve our likelihood of identifying effective and selective targets.
Collapse
|
22
|
Li H, Cheng Y, Wu W, Liu Y, Wei N, Feng X, Xie Z, Feng Y. SRSF10 regulates alternative splicing and is required for adipocyte differentiation. Mol Cell Biol 2014; 34:2198-207. [PMID: 24710272 DOI: 10.1128/MCB.01674-13] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
During adipocyte differentiation, significant alternative splicing changes occur in association with the adipogenic process. However, little is known about roles played by splicing factors in this process. We observed that mice deficient for the splicing factor SRSF10 exhibit severely impaired development of subcutaneous white adipose tissue (WAT) as a result of defects in adipogenic differentiation. To identify splicing events responsible for this, transcriptome sequencing (RNA-seq) analysis was performed using embryonic fibroblast cells. Several SRSF10-affected splicing events that are implicated in adipogenesis have been identified. Notably, lipin1, known as an important regulator during adipogenesis, was further investigated. While lipin1β is mainly involved in lipogenesis, its alternatively spliced isoform lipin1α, generated through the skipping of exon 7, is primarily required for initial adipocyte differentiation. Skipping of exon 7 is controlled by an SRSF10-regulated cis element located in the constitutive exon 8. The activity of this element depends on the binding of SRSF10 and correlates with the relative abundance of lipin1α mRNA. A series of experiments demonstrated that SRSF10 controls the production of lipin1α and thus promotes adipocyte differentiation. Indeed, lipin1α expression could rescue SRSF10-mediated adipogenic defects. Taken together, our results identify SRSF10 as an essential regulator for adipocyte differentiation and also provide new insights into splicing control by SRSF10 in lipin1 pre-mRNA splicing.
Collapse
|
23
|
Abstract
The thyroid hormone (TH) plays a significant role in diverse processes related to growth, development, differentiation, and metabolism. TH signaling modulates energy expenditure through both central and peripheral pathways. At the cellular level, the TH exerts its effects after concerted mechanisms facilitate binding to the TH receptor. In the hypothalamus, signals from a range of metabolic pathways, including appetite, temperature, afferent stimuli via the autonomic nervous system, availability of energy substrates, hormones, and other biologically active molecules, converge to maintain plasma TH at the appropriate level to preserve energy homeostasis. At the tissue level, TH actions on metabolism are controlled by transmembrane transporters, deiodinases, and TH receptors. In the modern environment, humans are susceptible to an energy surplus, which has resulted in an obesity epidemic and, thus, understanding the contribution of the TH to cellular and organism metabolism is increasingly relevant.
Collapse
Affiliation(s)
- Elizabeth A McAninch
- Division of Endocrinology, Diabetes, and Metabolism, University of Miami Miller School of Medicine, Miami, Florida
| | | |
Collapse
|
24
|
Abstract
Nuclear receptors are transcription factors that regulate gene expression through the ligand-controlled recruitment of a diverse group of proteins known as coregulators. Most nuclear receptor coregulators function in large multi-protein complexes that modify chromatin and thereby regulate the transcription of target genes. Structural and functional studies are beginning to reveal how these complexes are assembled bringing together multiple functionalities that mediate: recruitment to specific genomic loci through interaction with transcription factors; recruitment of enzymatic activities that either modify or remodel chromatin and targeting the complexes to their chromatin substrate. These activities are regulated by post-translational modifications, alternative splicing and small signalling molecules. This review focuses on our current understanding of coregulator complexes and aims to highlight the common principles that are beginning to emerge.
Collapse
Affiliation(s)
- Christopher J. Millard
- Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Leicester, LE1 9HN. UK
| | - Peter J. Watson
- Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Leicester, LE1 9HN. UK
| | - Louise Fairall
- Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Leicester, LE1 9HN. UK
| | - John W.R. Schwabe
- Henry Wellcome Laboratories of Structural Biology, Department of Biochemistry, University of Leicester, Leicester, LE1 9HN. UK
- Correspondence to:
| |
Collapse
|
25
|
Abstract
Epigenetic regulation of gene expression is strongly influenced by the accessibility of nucleosomal DNA or the state of chromatin compaction. In this context, coregulators, including both coactivators and corepressors, are pivotal intermediates that bridge chromatin-modifying enzymes and transcription factors. NCoR1 (nuclear receptor corepressor) and SMRT (silencing mediator of retinoic acid and thyroid hormone receptor) are among the best-characterized corepressors from a molecular point of view. These coregulators have conserved orthologs in lower organisms, which underscores their functional importance. Here we summarize the results from recent in vivo studies that reveal the wide-ranging roles of NCoR1 and SMRT in developmental as well as homeostatic processes, including metabolism, inflammation, and circadian rhythms. We also discuss the potential implications of NCoR1 and SMRT regulation of pathways ranging from genomic stability and carcinogenesis to metabolic diseases such as type 2 diabetes.
Collapse
Affiliation(s)
- Adrienne Mottis
- Laboratory for Integrative and Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, Lausanne CH-1015, Switzerland
| | | | | |
Collapse
|
26
|
Abstract
TSH is the most important biomarker in the interpretation of thyroid function in man. Its levels are determined by circulating thyroid hormone (TH) levels that feed back centrally to regulate the expression of the subunits that comprise TSH from the pituitary. The nuclear corepressor 1 (NCoR1), is a critical coregulator of the TH receptor (TR) isoforms. It has been established to play a major role in the control of TSH secretion, because mice that express a mutant NCoR1 allele (NCoRΔID) that cannot interact with the TR have normal TSH levels despite low circulating TH levels. To determine how NCoR1 controls TSH secretion, we first developed a mouse model that allowed for induction of NCoRΔID expression postnatally to rule out a developmental effect of NCoR1. Expression of NCoRΔID postnatally led to a drop in TH levels without a compensatory rise in TSH production, indicating that NCoR1 acutely controls both TH production and feedback regulation of TSH. To demonstrate that this was a cell autonomous function of NCoR1, we expressed NCoRΔID in the pituitary using a Cre driven by the glycoprotein α-subunit promoter (P-ΔID mice). Importantly, P-ΔID mice have low TH levels with decreased TSH production. Additionally, the rise in TSH during hypothyroidism is blunted in P-ΔID mice. Thus, NCoR1 plays a critical role in TH-mediated regulation of TSH in the pituitary by regulating the repressive function of the TR. Furthermore, these studies suggest that endogenous NCoR1 levels in the pituitary could establish the set point of TSH secretion.
Collapse
Affiliation(s)
- Ricardo H Costa-e-Sousa
- Division of Endocrinology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA
| | | | | | | | | |
Collapse
|
27
|
Huang L, Jin SY, Xu YO, Li YP, Lin YQ, Zheng YC. Quantitation of alternative splicing variants of lactate dehydrogenase C gene in testes of adult yak, sexually immature yak calf and sterile male hybrid of yak. Can J Anim Sci 2012. [DOI: 10.4141/cjas2012-018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Huang, L., Jin, S-Y., Xu, Y-O., Li, Y-P., Lin, Y-Q. and Zheng, Y-C. 2012. Quantitation of alternative splicing variants of lactate dehydrogenase C gene in testes of adult yak, sexually immature yak calf and sterile male hybrid of yak. Can. J. Anim. Sci. 92: 291–296. The main objective of the present study was to analyze quantitatively the alternative splicing of the lactate dehydrogenase C (ldhc) gene in the testes of yak (Bos grunniens) and male sterile yak hybrid. RT-PCR amplification of ldhc cDNA in the testes revealed eight splice variants formed by the deletion of one or more exons in the mRNA transcripts. The deleted exons occur mostly in exons 7 and 4. The deletion of exons caused reading frame shift and formation of stop codon in some variants. Quantitative real-time RT-PCR analysis using ldhc variant-specific primers showed that the mRNA level of full length ldhc decreased dramatically in the testes of sexually immature yak calf (n=6) and male sterile hybrid cattle–yak (n=4) compared with that of adult yak (n=14). The proportions of the ldhc variants assayed differed significantly among adult yak, yak calf and cattle–yak; more ldhc transcripts were spliced in immature or sterile testes. Our results suggest that the alternative splicing could play a role in the regulation of ldhc expression in testes, and could be one factor that plays a role in infertility of yak hybrids.
Collapse
Affiliation(s)
- Lin Huang
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu, 610041, P.R. China
| | - Su-Yu Jin
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu, 610041, P.R. China
| | - Ya-Ou Xu
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu, 610041, P.R. China
| | - Yu-Ping Li
- Agricultural and Animal Husbandry Bureau of Jiulong County, Jiulong, Sichuan Province, 626200, P.R. China
| | - Ya-Qiu Lin
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu, 610041, P.R. China
| | - Yu-Cai Zheng
- College of Life Science and Technology, Southwest University for Nationalities, Chengdu, 610041, P.R. China
| |
Collapse
|
28
|
Huang L, Lin Y, Jin S, Liu W, Xu Y, Zheng Y. Alternative Splicing of Testis-Specific Lactate Dehydrogenase C Gene in Mammals and Pigeon. Anim Biotechnol 2012; 23:114-23. [DOI: 10.1080/10495398.2011.652325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|