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Xu Y, Zhang H, Chen Y, Pober JS, Zhou M, Zhou JH, Min W. SRF SUMOylation modulates smooth muscle phenotypic switch and vascular remodeling. Nat Commun 2024; 15:6919. [PMID: 39134547 PMCID: PMC11319592 DOI: 10.1038/s41467-024-51350-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 08/05/2024] [Indexed: 08/15/2024] Open
Abstract
Serum response factor (SRF) controls gene transcription in vascular smooth muscle cells (VSMCs) and regulates VSMC phenotypic switch from a contractile to a synthetic state, which plays a key role in the pathogenesis of cardiovascular diseases (CVD). It is not known how post-translational SUMOylation regulates the SRF activity in CVD. Here we show that Senp1 deficiency in VSMCs increased SUMOylated SRF and the SRF-ELK complex, leading to augmented vascular remodeling and neointimal formation in mice. Mechanistically, SENP1 deficiency in VSMCs increases SRF SUMOylation at lysine 143, reducing SRF lysosomal localization concomitant with increased nuclear accumulation and switching a contractile phenotype-responsive SRF-myocardin complex to a synthetic phenotype-responsive SRF-ELK1 complex. SUMOylated SRF and phospho-ELK1 are increased in VSMCs from coronary arteries of CVD patients. Importantly, ELK inhibitor AZD6244 prevents the shift from SRF-myocardin to SRF-ELK complex, attenuating VSMC synthetic phenotypes and neointimal formation in Senp1-deficient mice. Therefore, targeting the SRF complex may have a therapeutic potential for the treatment of CVD.
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Affiliation(s)
- Yue Xu
- Interdepartmental Program in Vascular Biology and Therapeutics, Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
- State Key Laboratory of Ophthalmology and Guangdong Province Key Laboratory of Ophthalmology and Visual Science, Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Haifeng Zhang
- Interdepartmental Program in Vascular Biology and Therapeutics, Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Yuxin Chen
- Cardiovascular Medical Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China
| | - Jordan S Pober
- Interdepartmental Program in Vascular Biology and Therapeutics, Department of Pathology, Yale University School of Medicine, New Haven, CT, USA
| | - Min Zhou
- Cardiovascular Medical Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China.
| | - Jenny Huanjiao Zhou
- Interdepartmental Program in Vascular Biology and Therapeutics, Department of Pathology, Yale University School of Medicine, New Haven, CT, USA.
| | - Wang Min
- Cardiovascular Medical Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, China.
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2
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Zogg H, Singh R, Ha SE, Wang Z, Jin B, Ha M, Dafinone M, Batalon T, Hoberg N, Poudrier S, Nguyen L, Yan W, Layden BT, Dugas LR, Sanders KM, Ro S. miR-10b-5p rescues leaky gut linked with gastrointestinal dysmotility and diabetes. United European Gastroenterol J 2023; 11:750-766. [PMID: 37723933 PMCID: PMC10576606 DOI: 10.1002/ueg2.12463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 07/31/2023] [Indexed: 09/20/2023] Open
Abstract
BACKGROUND/AIM Diabetes has substantive co-occurrence with disorders of gut-brain interactions (DGBIs). The pathophysiological and molecular mechanisms linking diabetes and DGBIs are unclear. MicroRNAs (miRNAs) are key regulators of diabetes and gut dysmotility. We investigated whether impaired gut barrier function is regulated by a key miRNA, miR-10b-5p, linking diabetes and gut dysmotility. METHODS We created a new mouse line using the Mb3Cas12a/Mb3Cpf1 endonuclease to delete mir-10b globally. Loss of function studies in the mir-10b knockout (KO) mice were conducted to characterize diabetes, gut dysmotility, and gut barrier dysfunction phenotypes in these mice. Gain of function studies were conducted by injecting these mir-10b KO mice with a miR-10b-5p mimic. Further, we performed miRNA-sequencing analysis from colonic mucosa from mir-10b KO, wild type, and miR-10b-5p mimic injected mice to confirm (1) deficiency of miR-10b-5p in KO mice, and (2) restoration of miR-10b-5p after the mimic injection. RESULTS Congenital loss of mir-10b in mice led to the development of hyperglycemia, gut dysmotility, and gut barrier dysfunction. Gut permeability was increased, but expression of the tight junction protein Zonula occludens-1 was reduced in the colon of mir-10b KO mice. Patients with diabetes or constipation- predominant irritable bowel syndrome, a known DGBI that is linked to leaky gut, had significantly reduced miR-10b-5p expression. Injection of a miR-10b-5p mimic in mir-10b KO mice rescued these molecular alterations and phenotypes. CONCLUSIONS Our study uncovered a potential pathophysiologic mechanism of gut barrier dysfunction that links both the diabetes and gut dysmotility phenotypes in mice lacking miR-10b-5p. Treatment with a miR-10b-5p mimic reversed the leaky gut, diabetic, and gut dysmotility phenotypes, highlighting the translational potential of the miR-10b-5p mimic.
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Affiliation(s)
- Hannah Zogg
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Rajan Singh
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Se Eun Ha
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Zhuqing Wang
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Byungchang Jin
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Mariah Ha
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Mirabel Dafinone
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Tylar Batalon
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Nicholas Hoberg
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Sandra Poudrier
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Linda Nguyen
- Division of Gastroenterology & HepatologyStanford University School of MedicineStanfordCaliforniaUSA
| | - Wei Yan
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Brian T. Layden
- Division of Endocrinology, Diabetes, and MetabolismDepartment of MedicineThe University of Illinois at ChicagoChicagoIllinoisUSA
- Jesse Brown Veterans Affairs Medical CenterChicagoIllinoisUSA
| | - Lara R. Dugas
- Loyola University ChicagoPublic Health SciencesMaywoodIllinoisUSA
- Division of Epidemiology & BiostatisticsSchool of Public HealthFaculty of Health SciencesUniversity of Cape TownCape TownSouth Africa
| | - Kenton M. Sanders
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
| | - Seungil Ro
- Department of Physiology and Cell BiologySchool of MedicineUniversity of NevadaRenoNevadaUSA
- RosVivo TherapeuticsApplied Research FacilityRenoNevadaUSA
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3
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Functional Implications and Clinical Potential of MicroRNAs in Irritable Bowel Syndrome: A Concise Review. Dig Dis Sci 2023; 68:38-53. [PMID: 35507132 PMCID: PMC9066399 DOI: 10.1007/s10620-022-07516-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 04/04/2022] [Indexed: 02/01/2023]
Abstract
MicroRNAs (miRNAs) are tiny (20-24 nucleotides long), non-coding, highly conserved RNA molecules that play a crucial role within the post-transcriptional regulation of gene expression via sequence-specific mechanisms. Since the miRNA transcriptome is involved in multiple molecular processes needed for cellular homeostasis, its altered expression can trigger the development and progression of several human pathologies. In this context, over the last few years, several relevant studies have demonstrated that dysregulated miRNAs affect a wide range of molecular mechanisms associated with irritable bowel syndrome (IBS), a common gastrointestinal disorder. For instance, abnormal miRNA expression in IBS patients is related to the alteration of intestinal permeability, visceral hyperalgesia, inflammatory pathways, and pain sensitivity. Besides, specific miRNAs are differentially expressed in the different subtypes of IBS, and therefore, they might be used as biomarkers for precise diagnosis of these pathological conditions. Accordingly, miRNAs have noteworthy potential as theragnostic targets for IBS. Hence, in this current review, we present an overview of the recent discoveries regarding the clinical relevance of miRNAs in IBS, which might be useful in the future for the development of miRNA-based drugs against this disorder.
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4
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Singh R, Zogg H, Ro S. Role of microRNAs in Disorders of Gut-Brain Interactions: Clinical Insights and Therapeutic Alternatives. J Pers Med 2021; 11:jpm11101021. [PMID: 34683162 PMCID: PMC8541612 DOI: 10.3390/jpm11101021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 12/12/2022] Open
Abstract
Disorders of gut–brain interactions (DGBIs) are heterogeneous in nature and intertwine with diverse pathophysiological mechanisms. Regular functioning of the gut requires complex coordinated interplay between a variety of gastrointestinal (GI) cell types and their functions are regulated by multiple mechanisms at the transcriptional, post-transcriptional, translational, and post-translational levels. MicroRNAs (miRNAs) are small non-coding RNA molecules that post-transcriptionally regulate gene expression by binding to specific mRNA targets to repress their translation and/or promote the target mRNA degradation. Dysregulation of miRNAs might impair gut physiological functions leading to DGBIs and gut motility disorders. Studies have shown miRNAs regulate gut functions such as visceral sensation, gut immune response, GI barrier function, enteric neuronal development, and GI motility. These biological processes are highly relevant to the gut where neuroimmune interactions are key contributors in controlling gut homeostasis and functional defects lead to DGBIs. Although extensive research has explored the pathophysiology of DGBIs, further research is warranted to bolster the molecular mechanisms behind these disorders. The therapeutic targeting of miRNAs represents an attractive approach for the treatment of DGBIs because they offer new insights into disease mechanisms and have great potential to be used in the clinic as diagnostic markers and therapeutic targets. Here, we review recent advances regarding the regulation of miRNAs in GI pacemaking cells, immune cells, and enteric neurons modulating pathophysiological mechanisms of DGBIs. This review aims to assess the impacts of miRNAs on the pathophysiological mechanisms of DGBIs, including GI dysmotility, impaired intestinal barrier function, gut immune dysfunction, and visceral hypersensitivity. We also summarize the therapeutic alternatives for gut microbial dysbiosis in DGBIs, highlighting the clinical insights and areas for further exploration. We further discuss the challenges in miRNA therapeutics and promising emerging approaches.
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Affiliation(s)
| | | | - Seungil Ro
- Correspondence: ; Tel.: +1-775-784-1462; Fax: +1-775-784-6903
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5
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Hong Y, Ren X, Liu W, Sun K, Chen B, Liu B, Yu X, Chen Q, Qian Q, Xie X, Jiang C. miR-128 participates in the pathogenesis of chronic constipation by regulating the p38α/M-CSF inflammatory signaling pathway. Am J Physiol Gastrointest Liver Physiol 2021; 321:G436-G447. [PMID: 34405716 DOI: 10.1152/ajpgi.00114.2021] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Chronic constipation (CC) is a gastrointestinal disorder that adversely affects the quality of life. MicroRNAs are involved in the pathogenesis of functional gastrointestinal disorders. This study aims to investigate the molecular mechanism of microRNA-128 in CC. Here, we successfully constructed a murine model of CC based on morphine and rhubarb. The expression of stem cell factor (SCF) and neuron-specific enolase (NSE) was low in the models. Using miRNA array and bioinformatic analysis, we predicted and confirmed the expression of miR-128 and its downstream target genes in CC model. Compared with the control group, CC group showed a significant downregulation of miR-128 and upregulation of p38α and macrophage colony-stimulating factors (M-CSFs). Moreover, we observed elevated inflammatory cytokine and decreased anti-inflammatory cytokine levels in colonic tissues. Furthermore, coculture assays indicated that regulating expression of miR-128 in colonic epithelial cells induced the secretion of IL-6 and TNF-α by macrophages. In conclusion, our study demonstrated that miR-128 regulated the p38α/M-CSF signaling pathway to promote chronic inflammatory responses and changes in the immune microenvironment of the colon, thereby offering potential insights into the pathogenesis of CC and therapeutic targets for its treatment.NEW & NOTEWORTHY In this study, we constructed a murine model and identified a novel signaling mechanism involved in the chronic constipation progression. Our findings on the role of miR-128/p38α/M-CSF axis provide new insights into the treatment of chronic constipation.
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Affiliation(s)
- Yuntian Hong
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China
| | - Xianghai Ren
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Colorectal and Anal Disease Research Center of Medical School, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Quality Control Center of Colorectal and Anal Surgery of Health Commission of Hubei Province, Wuhan, People's Republic of China
| | - Weicheng Liu
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Colorectal and Anal Disease Research Center of Medical School, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Quality Control Center of Colorectal and Anal Surgery of Health Commission of Hubei Province, Wuhan, People's Republic of China
| | - Kongliang Sun
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China
| | - Baoxiang Chen
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China
| | - Bo Liu
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China
| | - Xueqiao Yu
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Colorectal and Anal Disease Research Center of Medical School, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Quality Control Center of Colorectal and Anal Surgery of Health Commission of Hubei Province, Wuhan, People's Republic of China
| | - Quanjiao Chen
- CAS Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Center for Biosafety Mega-Science, CAS Center for Influenza Research and Early Warning, Chinese Academy of Sciences, Wuhan, People's Republic of China
| | - Qun Qian
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Colorectal and Anal Disease Research Center of Medical School, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Quality Control Center of Colorectal and Anal Surgery of Health Commission of Hubei Province, Wuhan, People's Republic of China
| | - Xiaoyu Xie
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Colorectal and Anal Disease Research Center of Medical School, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Quality Control Center of Colorectal and Anal Surgery of Health Commission of Hubei Province, Wuhan, People's Republic of China
| | - Congqing Jiang
- Department of Colorectal and Anal Surgery, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Clinical Center of Intestinal and Colorectal Diseases of Hubei Province, Wuhan, People's Republic of China.,Hubei Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Colorectal and Anal Disease Research Center of Medical School, Zhongnan Hospital of Wuhan University, Wuhan, People's Republic of China.,Quality Control Center of Colorectal and Anal Surgery of Health Commission of Hubei Province, Wuhan, People's Republic of China
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6
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Singh R, Ha SE, Wei L, Jin B, Zogg H, Poudrier SM, Jorgensen BG, Park C, Ronkon CF, Bartlett A, Cho S, Morales A, Chung YH, Lee MY, Park JK, Gottfried-Blackmore A, Nguyen L, Sanders KM, Ro S. miR-10b-5p Rescues Diabetes and Gastrointestinal Dysmotility. Gastroenterology 2021; 160:1662-1678.e18. [PMID: 33421511 PMCID: PMC8532043 DOI: 10.1053/j.gastro.2020.12.062] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 12/18/2020] [Accepted: 12/26/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND & AIMS Interstitial cells of Cajal (ICCs) and pancreatic β cells require receptor tyrosine kinase (KIT) to develop and function properly. Degeneration of ICCs is linked to diabetic gastroparesis. The mechanisms linking diabetes and gastroparesis are unclear, but may involve microRNA (miRNA)-mediated post-transcriptional gene silencing in KIT+ cells. METHODS We performed miRNA-sequencing analysis from isolated ICCs in diabetic mice and plasma from patients with idiopathic and diabetic gastroparesis. miR-10b-5p target genes were identified and validated in mouse and human cell lines. For loss-of-function studies, we used KIT+ cell-restricted mir-10b knockout mice and KIT+ cell depletion mice. For gain-of-function studies, a synthetic miR-10b-5p mimic was injected in multiple diabetic mouse models. We compared the efficacy of miR-10b-5p mimic treatment vs antidiabetic and prokinetic medicines. RESULTS miR-10b-5p is highly expressed in ICCs from healthy mice, but drastically depleted in ICCs from diabetic mice. A conditional knockout of mir-10b in KIT+ cells or depletion of KIT+ cells in mice leads to degeneration of β cells and ICCs, resulting in diabetes and gastroparesis. miR-10b-5p targets the transcription factor Krüppel-like factor 11 (KLF11), which negatively regulates KIT expression. The miR-10b-5p mimic or Klf11 small interfering RNAs injected into mir-10b knockout mice, diet-induced diabetic mice, and TALLYHO polygenic diabetic mice rescue the diabetes and gastroparesis phenotype for an extended period of time. Furthermore, the miR-10b-5p mimic is more effective in improving glucose homoeostasis and gastrointestinal motility compared with common antidiabetic and prokinetic medications. CONCLUSIONS miR-10b-5p is a key regulator in diabetes and gastrointestinal dysmotility via the KLF11-KIT pathway. Restoration of miR-10b-5p may provide therapeutic benefits for these disorders.
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Affiliation(s)
- Rajan Singh
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Se Eun Ha
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Lai Wei
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Byungchang Jin
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Hannah Zogg
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Sandra M. Poudrier
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Brian G. Jorgensen
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Chanjae Park
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Charles F Ronkon
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Allison Bartlett
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Sung Cho
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Addison Morales
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Yu Heon Chung
- Division of Biological Sciences, Wonkwang University, Iksan, Chonbuk, Korea
| | - Moon Young Lee
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA,Department of Physiology, Wonkwang Digestive Disease Research Institute and Institute of Wonkwang Medical Science, School of Medicine, Wonkwang University, Iksan, Chonbuk, Korea
| | - Jong Kun Park
- Division of Biological Sciences, Wonkwang University, Iksan, Chonbuk, Korea
| | - Andrés Gottfried-Blackmore
- Division of Gastroenterology & Hepatology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Linda Nguyen
- Division of Gastroenterology & Hepatology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Kenton M. Sanders
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, NV, 89557, USA
| | - Seungil Ro
- Department of Physiology and Cell Biology, School of Medicine, University of Nevada, Reno, Nevada.
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7
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Singh R, Wei L, Ghoshal UC. Micro-organic basis of functional gastrointestinal (GI) disorders: Role of microRNAs in GI pacemaking cells. Indian J Gastroenterol 2021; 40:102-110. [PMID: 33738768 DOI: 10.1007/s12664-021-01159-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Rajan Singh
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, NV, 89557, USA
| | - Lai Wei
- Department of Physiology and Cell Biology, University of Nevada, Reno, School of Medicine, Reno, NV, 89557, USA
| | - Uday C Ghoshal
- Department of Gastroenterology, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, 226 014, India.
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8
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Liu R, Xiong X, Nam D, Yechoor V, Ma K. SRF-MRTF signaling suppresses brown adipocyte development by modulating TGF-β/BMP pathway. Mol Cell Endocrinol 2020; 515:110920. [PMID: 32603734 PMCID: PMC7484394 DOI: 10.1016/j.mce.2020.110920] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/05/2020] [Accepted: 06/19/2020] [Indexed: 12/21/2022]
Abstract
The SRF/MRTF and upstream signaling cascade play key roles in actin cytoskeleton organization and myocyte development. To date, how this signaling axis may function in brown adipocyte lineage commitment and maturation has not been delineated. Here we report that MRTF-SRF signaling exerts inhibitory actions on brown adipogenesis, and suppressing this negative regulation promotes brown adipocyte lineage development. During brown adipogenic differentiation, protein expressions of SRF, MRTFA/B and its transcription targets were down-regulated, and MRTFA/B shuttled from nucleus to cytoplasm. Silencing of SRF or MRTF-A/MRTF-B enhanced two distinct stages of brown adipocyte development, mesenchymal stem cell determination to brown adipocytes and terminal differentiation of brown adipogenic progenitors. We further demonstrate that the MRTF-SRF axis exerts transcriptional regulations of the TGF-β and BMP signaling pathway, critical developmental cues for brown adipocyte development. TGF-β signaling activity was significantly attenuated, whereas that of the BMP pathway augmented by inhibition of SRF or MRTF-A/MRTF-B, leading to enhanced brown adipocyte differentiation. Our study demonstrates the MRTF-SRF transcriptional cascade as a negative regulator of brown adipogenesis, through its transcriptional control of the TGF-β/BMP signaling pathways.
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Affiliation(s)
- Ruya Liu
- Diabetes and Beta Cell Biology Center, Division of Endocrinology, Diabetes & Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA.
| | - Xuekai Xiong
- Department of Diabetes Complications & Metabolism, Beckman Research Institute of City of Hope, Duarte, CA, 91010, USA
| | - Deokhwa Nam
- Center for Bioenergetics, Houston Methodist Research Institute, Houston, TX, 77030, USA
| | - Vijay Yechoor
- Diabetes and Beta Cell Biology Center, Division of Endocrinology, Diabetes & Metabolism, Department of Medicine, University of Pittsburgh, Pittsburgh, PA, 15213, USA
| | - Ke Ma
- Department of Diabetes Complications & Metabolism, Beckman Research Institute of City of Hope, Duarte, CA, 91010, USA.
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9
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Uray K, Major E, Lontay B. MicroRNA Regulatory Pathways in the Control of the Actin-Myosin Cytoskeleton. Cells 2020; 9:E1649. [PMID: 32660059 PMCID: PMC7408560 DOI: 10.3390/cells9071649] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/03/2020] [Accepted: 07/07/2020] [Indexed: 12/12/2022] Open
Abstract
MicroRNAs (miRNAs) are key modulators of post-transcriptional gene regulation in a plethora of processes, including actin-myosin cytoskeleton dynamics. Recent evidence points to the widespread effects of miRNAs on actin-myosin cytoskeleton dynamics, either directly on the expression of actin and myosin genes or indirectly on the diverse signaling cascades modulating cytoskeletal arrangement. Furthermore, studies from various human models indicate that miRNAs contribute to the development of various human disorders. The potentially huge impact of miRNA-based mechanisms on cytoskeletal elements is just starting to be recognized. In this review, we summarize recent knowledge about the importance of microRNA modulation of the actin-myosin cytoskeleton affecting physiological processes, including cardiovascular function, hematopoiesis, podocyte physiology, and osteogenesis.
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Affiliation(s)
- Karen Uray
- Correspondence: (K.U.); (B.L.); Tel.: +36-52-412345 (K.U. & B.L.)
| | | | - Beata Lontay
- Correspondence: (K.U.); (B.L.); Tel.: +36-52-412345 (K.U. & B.L.)
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10
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Gastric smooth muscle cells manifest an abnormal phenotype in Parkinson's disease rats with gastric dysmotility. Cell Tissue Res 2020; 381:217-227. [PMID: 32424507 DOI: 10.1007/s00441-020-03214-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 04/01/2020] [Indexed: 12/13/2022]
Abstract
Gastroparesis is a common symptom in Parkinson's disease (PD) and whether any change occurs in gastric smooth muscle cells (SMCs) of PD patients is unclear. We previously reported that rats with bilateral substantia nigra lesions induced by 6-hydroxydopamine (6-OHDA), referred to as 6-OHDA rats, manifest typical gastroparesis. In the present study, we further investigate the underlying mechanism. By means of an organ bath system and an implantable radiotelemetry system, both a weakened contractile force of gastric circular smooth muscle and gastric myoelectric activity were detected in the 6-OHDA rats and phasic and tonic contractions elicited by carbachol or high concentration of potassium were significantly reduced in gastric circular muscle strips. A thickened smooth muscle layer was observed under a light microscope and an ultrastructure of hypertrophic SMCs, with increased caveolae and decreased dense bodies, was observed under transmission electron microscope. Furthermore, the mRNA and protein expression levels of contractile markers (myosin light chain 20, myosin heavy chain 11 and α-smooth muscle actin) and the transcription factor serum response factor (SRF) were significantly decreased, while the TNFα and IL-1β content was increased in the 6-OHDA rats. These results suggest that the decreased contractile force in 6-OHDA rats may be associated with the phenotypic abnormality observed in SMCs, which is due to downregulated contractile proteins induced by decreased SRF expression in the inflammatory muscular microenvironment.
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11
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Mazzone A, Strege PR, Gibbons SJ, Alcaino C, Joshi V, Haak AJ, Tschumperlin DJ, Bernard CE, Cima RR, Larson DW, Chua HK, Graham RP, El Refaey M, Mohler PJ, Hayashi Y, Ordog T, Calder S, Du P, Farrugia G, Beyder A. microRNA overexpression in slow transit constipation leads to reduced Na V1.5 current and altered smooth muscle contractility. Gut 2020; 69:868-876. [PMID: 31757880 PMCID: PMC7147984 DOI: 10.1136/gutjnl-2019-318747] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 10/16/2019] [Accepted: 11/06/2019] [Indexed: 12/13/2022]
Abstract
OBJECTIVE This study was designed to evaluate the roles of microRNAs (miRNAs) in slow transit constipation (STC). DESIGN All human tissue samples were from the muscularis externa of the colon. Expression of 372 miRNAs was examined in a discovery cohort of four patients with STC versus three age/sex-matched controls by a quantitative PCR array. Upregulated miRNAs were examined by quantitative reverse transcription qPCR (RT-qPCR) in a validation cohort of seven patients with STC and age/sex-matched controls. The effect of a highly differentially expressed miRNA on a custom human smooth muscle cell line was examined in vitro by RT-qPCR, electrophysiology, traction force microscopy, and ex vivo by lentiviral transduction in rat muscularis externa organotypic cultures. RESULTS The expression of 13 miRNAs was increased in STC samples. Of those miRNAs, four were predicted to target SCN5A, the gene that encodes the Na+ channel NaV1.5. The expression of SCN5A mRNA was decreased in STC samples. Let-7f significantly decreased Na+ current density in vitro in human smooth muscle cells. In rat muscularis externa organotypic cultures, overexpression of let-7f resulted in reduced frequency and amplitude of contraction. CONCLUSIONS A small group of miRNAs is upregulated in STC, and many of these miRNAs target the SCN5A-encoded Na+ channel NaV1.5. Within this set, a novel NaV1.5 regulator, let-7f, resulted in decreased NaV1.5 expression, current density and reduced motility of GI smooth muscle. These results suggest NaV1.5 and miRNAs as novel diagnostic and potential therapeutic targets in STC.
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Affiliation(s)
- Amelia Mazzone
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Peter R Strege
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Simon J Gibbons
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Constanza Alcaino
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Vikram Joshi
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Andrew J Haak
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Daniel J Tschumperlin
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Cheryl E Bernard
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Robert R Cima
- Department of Colon and Rectal Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - David W Larson
- Department of Colon and Rectal Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | - Heidi K Chua
- Department of Colon and Rectal Surgery, Mayo Clinic, Rochester, Minnesota, USA
| | | | - Mona El Refaey
- Departments of Physiology and Cell Biology, The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA,Department of Internal Medicine, The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Peter J Mohler
- Departments of Physiology and Cell Biology, The Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Yujiro Hayashi
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Tamas Ordog
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Stefan Calder
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Peng Du
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Gianrico Farrugia
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA .,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
| | - Arthur Beyder
- Enteric NeuroScience Program (ENSP), Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota, USA .,Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, Minnesota, USA
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12
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Hwang YH, Jung SA, Lyu J, Kim YY, Lee JH. Transforming Growth Factor-β1-induced Human Subconjunctival Fibrosis is Mediated by MicroRNA 143/145 Expression. Invest Ophthalmol Vis Sci 2019; 60:2064-2071. [PMID: 31081880 DOI: 10.1167/iovs.19-26797] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose To investigate the roles and pathways of microRNAs 143 and 145 in transforming growth factor (TGF)-β1-induced human subconjunctival fibrosis. Methods Human tenon's capsule fibroblasts (HTFs) were obtained from a healthy eye. After treating cultured HTFs with TGF-β1, the expression of microRNAs 143 and 145 was evaluated using polymerase chain reaction. To identify the pathways of TGF-β1-induced microRNA 143/145 expression, HTFs were treated with specific inhibitors of p38MAPK, PI3K/Akt, JNK, ERK, and with siRNAs for SMAD2 and SMAD4. Mutagenesis studies were performed to evaluate the role of the CArG box and SMAD-binding element (SBE). To investigate the role of microRNA 143/145 in TGF-β1-induced myofibroblast transdifferentiation, microRNA 143/145 mimics and microRNA 143/145 inhibitors were applied to the HTFs. Results Array analysis revealed that TGF-β1 induced the expression of microRNA 143/145 in a dose- and time-dependent manner. When inhibitors and siRNAs for p38MAPK, PI3K/Akt, ERK, and JNK were applied, the TGF-β1-induced expression of microRNA 143/145 was inhibited; however, SMAD2 and SMAD4 inhibition did not affect the TGF-β1-induced expression of these microRNAs. In the mutagenesis studies, both the CArG box and SBE were associated with TGF-β1-induced expression of microRNA 143/145. Mimics of microRNA 143/145 induced increased myofibroblast formation, whereas their inhibitors had the opposite effect. Conclusions TGF-β1-induced human subconjunctival fibrosis was mediated by the expression of microRNA 143/145, mainly via SMAD-independent pathways. Inhibition of TGF-β1-induced microRNA 143/145 expression in HTFs might represent a novel strategy to prevent subconjunctival fibrosis.
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Affiliation(s)
- Young Hoon Hwang
- Myung-Gok Eye Research Institute, Kim's Eye Hospital, Konyang University College of Medicine, Seoul, Korea
| | - Sun-Ah Jung
- Myung-Gok Eye Research Institute, Kim's Eye Hospital, Konyang University College of Medicine, Seoul, Korea
| | - Jungmook Lyu
- Department of Medical Science, Konyang University, Daejeon, Korea
| | - Yong Yeon Kim
- Department of Ophthalmology, Korea University College of Medicine, Seoul, Korea
| | - Joon H Lee
- Myung-Gok Eye Research Institute, Kim's Eye Hospital, Konyang University College of Medicine, Seoul, Korea.,Department of Cell Biology, Konyang University, Daejeon, Korea
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13
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Deng JJ, Lai MY, Tan X, Yuan Q. Acupuncture protects the interstitial cells of Cajal by regulating miR-222 in a rat model of post-operative ileus. Acupunct Med 2019; 37:125-132. [PMID: 30852906 DOI: 10.1177/0964528419829755] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND Recovery of the interstitial cells of Cajal (ICCs) during post-operative ileus (POI) is important for the restoration of gastrointestinal (GI) motility. Acupuncture can protect ICCs, but the underlying mechanisms remain unclear. In this study, we investigated whether miR-222, c-kit and endothelial nitric oxide synthase (eNOS) are involved in the putative effects of acupuncture on ICC recovery. METHODS A POI model was established in Sprague-Dawley rats by colo-colic anastomosis, and then acupuncture was performed at bilateral ST36, SP6 and LR3 once daily for 3 consecutive days. C-kit protein expression in the colonic tissue adjacent to the incision site was determined by immunohistochemistry and Western blotting. mRNA levels of c-kit, eNOS and miR-222 were measured by real-time polymerase chain reaction (RT-PCR). RESULTS The levels of c-kit mRNA/protein and eNOS mRNA decreased, while miR-222 increased in the colonic tissues of POI model rats. Acupuncture treatment improved GI motility, inhibited the up-regulation of miR-222 and blocked the down-regulation of c-kit mRNA/protein and eNOS mRNA. The levels of miR-222 and c-kit were negatively correlated. CONCLUSION Acupuncture at ST36, SP6 and LR3 facilitates ICC recovery and improves post-operative GI motility in part through regulation of miR-222, c-kit and eNOS.
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Affiliation(s)
- Jing-Jing Deng
- 1 Department of Chinese Medicine, Guangzhou 8th People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Ming-Yin Lai
- 2 Clinical Medical College of Acupuncture, Moxibustion and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xinghua Tan
- 1 Department of Chinese Medicine, Guangzhou 8th People's Hospital, Guangzhou Medical University, Guangzhou, China
| | - Qing Yuan
- 2 Clinical Medical College of Acupuncture, Moxibustion and Rehabilitation, Guangzhou University of Chinese Medicine, Guangzhou, China
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14
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Jorgensen BG, Berent RM, Ha SE, Horiguchi K, Sasse KC, Becker LS, Ro S. DNA methylation, through DNMT1, has an essential role in the development of gastrointestinal smooth muscle cells and disease. Cell Death Dis 2018; 9:474. [PMID: 29700293 PMCID: PMC5920081 DOI: 10.1038/s41419-018-0495-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 01/31/2018] [Accepted: 02/12/2018] [Indexed: 12/24/2022]
Abstract
DNA methylation is a key epigenetic modification that can regulate gene expression. Genomic DNA hypomethylation is commonly found in many gastrointestinal (GI) diseases. Dysregulated gene expression in GI smooth muscle cells (GI-SMCs) can lead to motility disorders. However, the consequences of genomic DNA hypomethylation within GI-SMCs are still elusive. Utilizing a Cre-lox murine model, we have generated SMC-restricted DNA methyltransferase 1 (Dnmt1) knockout (KO) mice and analyzed the effects of Dnmt1 deficiency. Dnmt1-KO pups are born smaller than their wild-type littermates, have shortened GI tracts, and lose peristaltic movement due to loss of the tunica muscularis in their intestine, causing massive intestinal dilation, and death around postnatal day 21. Within smooth muscle tissue, significant CpG hypomethylation occurs across the genome at promoters, introns, and exons. Additionally, there is a marked loss of differentiated SMC markers (Srf, Myh11, miR-133, miR-143/145), an increase in pro-apoptotic markers (Nr4a1, Gadd45g), loss of cellular connectivity, and an accumulation of coated vesicles within SMC. Interestingly, we observed consistent abnormal expression patterns of enzymes involved in DNA methylation between both Dnmt1-KO mice and diseased human GI tissue. These data demonstrate that DNA hypomethylation in embryonic SMC, via congenital Dnmt1 deficiency, contributes to massive dysregulation of gene expression and is lethal to GI-SMC. These results suggest that Dnmt1 has a necessary role in the embryonic, primary development process of SMC with consistent patterns being found in human GI diseased tissue.
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Affiliation(s)
- Brian G Jorgensen
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV, 89557, USA
| | - Robyn M Berent
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV, 89557, USA
| | - Se Eun Ha
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV, 89557, USA
| | - Kazuhide Horiguchi
- Department of Morphological and Physiological Sciences, University of Fukui, Fukui, 910-8507, Japan
| | | | - Laren S Becker
- Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, CA, 94305, USA
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV, 89557, USA.
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15
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Guo B, Lyu Q, Slivano OJ, Dirkx R, Christie CK, Czyzyk J, Hezel AF, Gharavi AG, Small EM, Miano JM. Serum Response Factor Is Essential for Maintenance of Podocyte Structure and Function. J Am Soc Nephrol 2017; 29:416-422. [PMID: 29114040 DOI: 10.1681/asn.2017050473] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 10/11/2017] [Indexed: 01/15/2023] Open
Abstract
Podocytes contain an intricate actin cytoskeleton that is essential for the specialized function of this cell type in renal filtration. Serum response factor (SRF) is a master transcription factor for the actin cytoskeleton, but the in vivo expression and function of SRF in podocytes are unknown. We found that SRF protein colocalizes with podocyte markers in human and mouse kidneys. Compared with littermate controls, mice in which the Srf gene was conditionally inactivated with NPHS2-Cre exhibited early postnatal proteinuria, hypoalbuminemia, and azotemia. Histologic changes in the mutant mice included glomerular capillary dilation and mild glomerulosclerosis, with reduced expression of multiple canonical podocyte markers. We also noted tubular dilation, cell proliferation, and protein casts as well as reactive changes in mesangial cells and interstitial inflammation. Ultrastructure analysis disclosed foot process effacement with loss of slit diaphragms. To ascertain the importance of SRF cofactors in podocyte function, we disabled the myocardin-related transcription factor A and B genes. Although loss of either SRF cofactor alone had no observable effect in the kidney, deficiency of both recapitulated the Srf-null phenotype. These results establish a vital role for SRF and two SRF cofactors in the maintenance of podocyte structure and function.
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Affiliation(s)
- Bing Guo
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York.,Department of Hepatobiliary Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Qing Lyu
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Orazio J Slivano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Ronald Dirkx
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Christine K Christie
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Jan Czyzyk
- Department of Pathology and Laboratory Medicine and
| | - Aram F Hezel
- James P. Wilmot Cancer Center, University of Rochester School of Medicine and Dentistry, Rochester, New York; and
| | - Ali G Gharavi
- Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York
| | - Eric M Small
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York
| | - Joseph M Miano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York;
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16
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Ha SE, Lee MY, Kurahashi M, Wei L, Jorgensen BG, Park C, Park PJ, Redelman D, Sasse KC, Becker LS, Sanders KM, Ro S. Transcriptome analysis of PDGFRα+ cells identifies T-type Ca2+ channel CACNA1G as a new pathological marker for PDGFRα+ cell hyperplasia. PLoS One 2017; 12:e0182265. [PMID: 28806761 PMCID: PMC5555714 DOI: 10.1371/journal.pone.0182265] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Accepted: 07/14/2017] [Indexed: 12/11/2022] Open
Abstract
Platelet-derived growth factor receptor alpha (PDGFRα)+ cells are distributed into distinct morphological groups within the serosal, muscular, and submucosal layers as well as the myenteric and deep muscular plexi. PDGFRα+ cells directly interact with interstitial cells of Cajal (ICC) and smooth muscle cells (SMC) in gastrointestinal smooth muscle tissue. These three cell types, SMC, ICC, and PDGFRα+ cells (SIP cells), form an electrical syncytium, which dynamically regulates gastrointestinal motility. We have previously reported the transcriptomes of SMC and ICC. To complete the SIP cell transcriptome project, we obtained transcriptome data from jejunal and colonic PDGFRα+ cells. The PDGFRα+ cell transcriptome data were added to the Smooth Muscle Genome Browser that we previously built for the genome-scale gene expression data of ICC and SMC. This browser provides a comprehensive reference for all transcripts expressed in SIP cells. By analyzing the transcriptomes, we have identified a unique set of PDGFRα+ cell signature genes, growth factors, transcription factors, epigenetic enzymes/regulators, receptors, protein kinases/phosphatases, and ion channels/transporters. We demonstrated that the low voltage-dependent T-type Ca2+ channel Cacna1g gene was particularly expressed in PDGFRα+ cells in the intestinal serosal layer in mice. Expression of this gene was significantly induced in the hyperplasic PDGFRα+ cells of obstructed small intestine in mice. This gene was also over-expressed in colorectal cancer, Crohn's disease, and diverticulitis in human patients. Taken together, our data suggest that Cacna1g exclusively expressed in serosal PDGFRα+ cells is a new pathological marker for gastrointestinal diseases.
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Affiliation(s)
- Se Eun Ha
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Moon Young Lee
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- Department of Physiology, Wonkwang Digestive Disease Research Institute and Institute of Wonkwang Medical Science, School of Medicine, Wonkwang University, Iksan, Chonbuk, Korea
| | - Masaaki Kurahashi
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Lai Wei
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Brian G. Jorgensen
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Chanjae Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Paul J. Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Doug Redelman
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Kent C. Sasse
- Sasse Surgical Associates, Reno, Nevada, United States of America
| | - Laren S. Becker
- Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, California, United States of America
| | - Kenton M. Sanders
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
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17
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Singh J, Mohanty I, Addya S, Phillips B, Mee Yong H, An SS, Penn RB, Rattan S. Role of differentially expressed microRNA-139-5p in the regulation of phenotypic internal anal sphincter smooth muscle tone. Sci Rep 2017; 7:1477. [PMID: 28469189 PMCID: PMC5431208 DOI: 10.1038/s41598-017-01550-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 03/27/2017] [Indexed: 12/19/2022] Open
Abstract
The present study focused on the role of microRNA-139-5p (miRNA-139-5p) in the regulation of basal tone in internal anal sphincter (IAS). Applying genome-wide miRNA microarrays on the phenotypically distinct smooth muscle cells (SMCs) within the rat anorectrum, we identified miRNA-139-5p as differentially expressed RNA repressor with highest expression in the purely phasic smooth muscle of anococcygeus (ASM) vs. the truly tonic smooth muscle of IAS. This pattern of miRNA-139-5p expression, previously shown to target ROCK2, was validated by target prediction using ingenuity pathway (IPA) and by qPCR analyses. Immunoblotting, immunocytochemistry (ICC), and functional assays using IAS tissues and cells subjected to overexpression/knockdown of miRNA-139-5p confirmed the inverse relationship between miRNA-139-5p and ROCK2 expressions/IAS tone. Overexpression of miRNA-139-5p caused a decrease, while knockdown by anti-miRNA-139-5p caused an increase in the IAS tone; these tissue contractile responses were confirmed by single-cell contraction using magnetic twisting cytometry (MTC). These findings suggest miRNA-139-5p is capable of significantly influencing the phenotypic tonicity in smooth muscle via ROCK2: a lack of tone in ASM may be associated with the suppression of ROCK2 by high expression of miRNA-139-5p, whereas basal IAS tone may be associated with the persistence of ROCK2 due to low expression of miRNA-139-5p.
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Affiliation(s)
- Jagmohan Singh
- Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, USA
| | - Ipsita Mohanty
- Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, USA
| | - Sankar Addya
- Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, PA, USA
| | - Benjamin Phillips
- Department of Surgery, Division of Colorectal Surgery, Thomas Jefferson University, Philadelphia, PA, USA
| | - Hwan Mee Yong
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Steven S An
- Department of Environmental Health and Engineering, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Raymond B Penn
- Center for Translational Medicine (RP), Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Satish Rattan
- Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, PA, USA.
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18
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Che M, Shi T, Feng S, Li H, Zhang X, Feng N, Lou W, Dou J, Tang G, Huang C, Xu G, Qian Q, Sun S, He L, Wang H. The MicroRNA-199a/214 Cluster Targets E-Cadherin and Claudin-2 and Promotes High Glucose-Induced Peritoneal Fibrosis. J Am Soc Nephrol 2017; 28:2459-2471. [PMID: 28428333 DOI: 10.1681/asn.2016060663] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 02/15/2017] [Indexed: 12/16/2022] Open
Abstract
Serum response factor (SRF) was found to be involved in the phenotypic transition and fibrosis of the peritoneal membrane during treatment with peritoneal dialysis (PD), but the exact mechanism remains unclear. SRF regulates microRNAs (miRNAs) that contain the SRF-binding consensus (CArG) element in the promoter region. Therefore, we investigated whether the miR-199a/214 gene cluster, which contains a CArG element in its promoter, is directly regulated by SRF. High-glucose (HG) treatment significantly unregulated the expression of the miR-199a-5p/214-3p gene cluster in human peritoneal mesothelial cells (HPMCs). By chromatin immunoprecipitation and reporter assays, we found that SRF binds to the miR-199a-5p/214-3p gene cluster promoter after HG stimulation. In vitro, in HPMCs, silencing of miR-199a-5p or miR-214-3p inhibited the HG-induced phenotypic transition and cell migration but enhanced cell adhesion, whereas ectopic expression of mimic oligonucleotides had the opposite effects. Both miR-199a-5p and miR-214-3p targeted claudin-2 and E-cadherin mRNAs. In a PD rat model, treatment with an SRF inhibitor silenced miR-199a-5p and miR-214-3p and alleviated HG-PD fluid-induced damage and fibrosis. Overall, this study reveals a novel SRF-miR-199a/miR-214-E-cadherin/claudin-2 axis that mediates damage and fibrosis in PD.
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Affiliation(s)
- Mingwen Che
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Nephrology, Beijing Shijitan Hospital, Capital Medical University, Beijing, China.,Department of Medicine, Hospital of PLA, Korla, Xinjiang, China
| | - Tiantian Shi
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Department of Medicine, Yangling Demonstration Zone Hospital, Yangling, Shaanxi, China; and
| | - Shidong Feng
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Huan Li
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Xiaomin Zhang
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Ning Feng
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Weijuan Lou
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Jianhua Dou
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Guangbo Tang
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Chen Huang
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Guoshuang Xu
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Qi Qian
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China.,Mayo Clinic Department of Medicine, Division of Nephrology and Hypertension, Mayo Clinic College of Medicine, Mayo Graduate School, Rochester, Minnesota
| | - Shiren Sun
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Lijie He
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China; .,Department of Nephrology, Beijing Shijitan Hospital, Capital Medical University, Beijing, China
| | - Hanmin Wang
- Department of Nephrology, State Key Laboratory of Cancer Biology and Institute of Digestive Diseases, Xijing Hospital, The Fourth Military Medical University, Xi'an, Shaanxi, China;
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19
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STARS knockout attenuates hypoxia-induced pulmonary arterial hypertension by suppressing pulmonary arterial smooth muscle cell proliferation. Biomed Pharmacother 2017; 87:397-404. [DOI: 10.1016/j.biopha.2016.12.126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2016] [Revised: 12/13/2016] [Accepted: 12/28/2016] [Indexed: 11/24/2022] Open
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20
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Lee MY, Park C, Ha SE, Park PJ, Berent RM, Jorgensen BG, Corrigan RD, Grainger N, Blair PJ, Slivano OJ, Miano JM, Ward SM, Smith TK, Sanders KM, Ro S. Serum response factor regulates smooth muscle contractility via myotonic dystrophy protein kinases and L-type calcium channels. PLoS One 2017; 12:e0171262. [PMID: 28152551 PMCID: PMC5289827 DOI: 10.1371/journal.pone.0171262] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 01/17/2017] [Indexed: 11/19/2022] Open
Abstract
Serum response factor (SRF) transcriptionally regulates expression of contractile genes in smooth muscle cells (SMC). Lack or decrease of SRF is directly linked to a phenotypic change of SMC, leading to hypomotility of smooth muscle in the gastrointestinal (GI) tract. However, the molecular mechanism behind SRF-induced hypomotility in GI smooth muscle is largely unknown. We describe here how SRF plays a functional role in the regulation of the SMC contractility via myotonic dystrophy protein kinase (DMPK) and L-type calcium channel CACNA1C. GI SMC expressed Dmpk and Cacna1c genes into multiple alternative transcriptional isoforms. Deficiency of SRF in SMC of Srf knockout (KO) mice led to reduction of SRF-dependent DMPK, which down-regulated the expression of CACNA1C. Reduction of CACNA1C in KO SMC not only decreased intracellular Ca2+ spikes but also disrupted their coupling between cells resulting in decreased contractility. The role of SRF in the regulation of SMC phenotype and function provides new insight into how SMC lose their contractility leading to hypomotility in pathophysiological conditions within the GI tract.
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Affiliation(s)
- Moon Young Lee
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- Department of Physiology, Wonkwang Digestive Disease Research Institute and Institute of Wonkwang Medical Science, School of Medicine, Wonkwang University, Iksan, Chonbuk, Korea
| | - Chanjae Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Se Eun Ha
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Paul J. Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Robyn M. Berent
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Brian G. Jorgensen
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Robert D. Corrigan
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Nathan Grainger
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Peter J. Blair
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Orazio J. Slivano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Joseph M. Miano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Sean M. Ward
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Terence K. Smith
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Kenton M. Sanders
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- * E-mail:
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Singh J, Boopathi E, Addya S, Phillips B, Rigoutsos I, Penn RB, Rattan S. Aging-associated changes in microRNA expression profile of internal anal sphincter smooth muscle: Role of microRNA-133a. Am J Physiol Gastrointest Liver Physiol 2016; 311:G964-G973. [PMID: 27634012 PMCID: PMC5130548 DOI: 10.1152/ajpgi.00290.2016] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 09/13/2016] [Indexed: 01/31/2023]
Abstract
A comprehensive genomic and proteomic, computational, and physiological approach was employed to examine the (previously unexplored) role of microRNAs (miRNAs) as regulators of internal anal sphincter (IAS) smooth muscle contractile phenotype and basal tone. miRNA profiling, genome-wide expression, validation, and network analyses were employed to assess changes in mRNA and miRNA expression in IAS smooth muscles from young vs. aging rats. Multiple miRNAs, including rno-miR-1, rno-miR-340-5p, rno-miR-185, rno-miR-199a-3p, rno-miR-200c, rno-miR-200b, rno-miR-31, rno-miR-133a, and rno-miR-206, were found to be upregulated in aging IAS. qPCR confirmed the upregulated expression of these miRNAs and downregulation of multiple, predicted targets (Eln, Col3a1, Col1a1, Zeb2, Myocd, Srf, Smad1, Smad2, Rhoa/Rock2, Fn1, Tagln v2, Klf4, and Acta2) involved in regulation of smooth muscle contractility. Subsequent studies demonstrated an aging-associated increase in the expression of miR-133a, corresponding decreases in RhoA, ROCK2, MYOCD, SRF, and SM22α protein expression, RhoA-signaling, and a decrease in basal and agonist [U-46619 (thromboxane A2 analog)]-induced increase in the IAS tone. Moreover, in vitro transfection of miR-133a caused a dose-dependent increase of IAS tone in strips, which was reversed by anti-miR-133a. Last, in vivo perianal injection of anti-miR-133a reversed the loss of IAS tone associated with age. This work establishes the important regulatory effect of miRNA-133a on basal and agonist-stimulated IAS tone. Moreover, reversal of age-associated loss of tone via anti-miR delivery strongly implicates miR dysregulation as a causal factor in the aging-associated decrease in IAS tone and suggests that miR-133a is a feasible therapeutic target in aging-associated rectoanal incontinence.
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Affiliation(s)
- Jagmohan Singh
- 1Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania;
| | - Ettickan Boopathi
- 2Center for Translational Medicine, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania;
| | - Sankar Addya
- 3Kimmel Cancer Center, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania;
| | - Benjamin Phillips
- 4Department of Surgery, Division of Colorectal Surgery, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania; and
| | - Isidore Rigoutsos
- 5Computational Medicine Center, Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Raymond B. Penn
- 2Center for Translational Medicine, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania;
| | - Satish Rattan
- 1Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania;
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22
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Coletti D, Daou N, Hassani M, Li Z, Parlakian A. Serum Response Factor in Muscle Tissues: From Development to Ageing. Eur J Transl Myol 2016; 26:6008. [PMID: 27478561 PMCID: PMC4942704 DOI: 10.4081/ejtm.2016.6008] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Skeletal, cardiac and smooth muscle cells share various common characteristic features. During development the embryonic mesodermal layer contribute at different proportions to the formation of these tissues. At the functional level, contractility as well as its decline during ageing, are also common features. Cytoskeletal components of these tissues are characterized by various actin isoforms that govern through their status (polymerised versus monomeric) and their interaction with the myosins the contractile properties of these muscles. Finally, at the molecular level, a set of different transcription factors with the notable exception of Serum Response Factor SRF- which is commonly enriched in the 3 types of muscle- drive and maintain the differentiation of these cells (Myf5, MyoD, Myogenin for skeletal muscle; Nkx2.5, GATA4 for cardiomyocytes). In this review, we will focus on the transcription factor SRF and its role in the homeostasis of cardiac, smooth and skeletal muscle tissues as well as its behaviour during the age related remodelling process of these tissues with a specific emphasis on animal models and human data when available.
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Affiliation(s)
- Dario Coletti
- Sorbonne University, UPMC, Department of Biological Adaptation and Ageing, IBPS, UMR 8256 CNRS, INSERM U1164, Paris, France; Dept of Anatomy, Histology, Forensic Medicine & Ortopedics, School of Medicine Sapienza University of Rome, Italy
| | - Nissrine Daou
- Sorbonne University, UPMC , Department of Biological Adaptation and Ageing, IBPS, UMR 8256 CNRS, INSERM U1164, Paris, France
| | - Medhi Hassani
- Sorbonne University, UPMC , Department of Biological Adaptation and Ageing, IBPS, UMR 8256 CNRS, INSERM U1164, Paris, France
| | - Zhenlin Li
- Sorbonne University, UPMC , Department of Biological Adaptation and Ageing, IBPS, UMR 8256 CNRS, INSERM U1164, Paris, France
| | - Ara Parlakian
- Sorbonne University, UPMC , Department of Biological Adaptation and Ageing, IBPS, UMR 8256 CNRS, INSERM U1164, Paris, France
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23
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Krishna CV, Singh J, Thangavel C, Rattan S. Role of microRNAs in gastrointestinal smooth muscle fibrosis and dysfunction: novel molecular perspectives on the pathophysiology and therapeutic targeting. Am J Physiol Gastrointest Liver Physiol 2016; 310:G449-59. [PMID: 26822916 PMCID: PMC4824177 DOI: 10.1152/ajpgi.00445.2015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 01/20/2016] [Indexed: 01/31/2023]
Abstract
MicroRNAs (miRNAs) belong to a group of short noncoding RNA molecules with important roles in cellular biology. miRNAs regulate gene expression by repressing translation or degrading the target mRNA. Recently, a growing body of evidence suggests that miRNAs are implicated in many diseases and could be potential biomarkers. Fibrosis and/smooth muscle (SM) dysfunction contributes to the morbidity and mortality associated with several diseases of the gastrointestinal tract (GIT). Currently available therapeutic modalities are unsuccessful in efficiently blocking or reversing fibrosis and/or SM dysfunction. Recent understanding of the role of miRNAs in signaling pathway of fibrogenesis and SM phenotype switch has provided a new insight into translational research. However, much is still unknown about the molecular targets and therapeutic potential of miRNAs in the GIT. This review discusses miRNA biology, pathophysiology of fibrosis, and aging- associated SM dysfunction in relation to the deregulation of miRNAs in the GIT. We also highlight the role of selected miRNAs associated with fibrosis and SM dysfunction-related diseases of the GIT.
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Affiliation(s)
| | - Jagmohan Singh
- 2Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania; and
| | - Chellappagounder Thangavel
- 3Department of Radiation Oncology, Sidney Kimmel Cancer Center (TC), Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Satish Rattan
- 2Department of Medicine, Division of Gastroenterology & Hepatology, Sidney Kimmel Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania; and
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24
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Ro S. Multi-phenotypic Role of Serum Response Factor in the Gastrointestinal System. J Neurogastroenterol Motil 2016; 22:193-200. [PMID: 26727951 PMCID: PMC4819857 DOI: 10.5056/jnm15183] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 12/26/2015] [Indexed: 12/12/2022] Open
Abstract
Serum response factor (SRF) is a master transcription factor of the actin cytoskeleton that binds to highly conserved CArG boxes located within the majority of smooth muscle cell (SMC)-restricted promoters/enhancers. Although most studies of SRF focus on skeletal muscle, cardiac muscle, and vascular SMCs, SRF research has recently expanded into the gastrointestinal (GI) system. Genome scale analyses of GI SMC transcriptome and CArG boxes (CArGome) have identified new SRF target genes. In addition to circular and longitudinal smooth muscle layers, SRF is also expressed in GI mucosa and cancers. In the GI tract, SRF is the central regulator of genes involved in apoptosis, dedifferentiation, proliferation, and migration of cells. Since SRF is the cell phenotypic modulator, it may play an essential role in the development of myopathy, hypertrophy, ulcers, gastric and colon cancers within the GI tract. Given the multi-functional role displayed by SRF in the digestive system, SRF has received more attention emerging as a potential therapeutic target. This review summarizes the findings in SRF research pertaining to the GI tract and provides valuable insight into future directions.
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Affiliation(s)
- Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, NV, USA
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25
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Scirocco A, Matarrese P, Carabotti M, Ascione B, Malorni W, Severi C. Cellular and Molecular Mechanisms of Phenotypic Switch in Gastrointestinal Smooth Muscle. J Cell Physiol 2016; 231:295-302. [PMID: 26206426 DOI: 10.1002/jcp.25105] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 07/21/2015] [Indexed: 10/16/2023]
Abstract
As a general rule, smooth muscle cells (SMC) are able to switch from a contractile phenotype to a less mature synthetic phenotype. This switch is accompanied by a loss of differentiation with decreased expression of contractile markers, increased proliferation as well as the synthesis and the release of several signaling molecules such as pro-inflammatory cytokines, chemotaxis-associated molecules, and growth factors. This SMC phenotypic plasticity has extensively been investigated in vascular diseases, but interest is also emerging in the field of gastroenterology. It has in fact been postulated that altered microenvironmental conditions, including the composition of microbiota, could trigger the remodeling of the enteric SMC, with phenotype changes and consequent alterations of contraction and impairment of gut motility. Several molecular actors participate in this phenotype remodeling. These include extracellular molecules such as cytokines and extracellular matrix proteins, as well as intracellular proteins, for example, transcription factors. Epigenetic control mechanisms and miRNA have also been suggested to participate. In this review key roles and actors of smooth muscle phenotypic switch, mainly in GI tissue, are described and discussed in the light of literature data available so far. J. Cell. Physiol. 231: 295-302, 2016. © 2015 Wiley Periodicals, Inc.
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Affiliation(s)
- Annunziata Scirocco
- Department of Internal Medicine and Medical Specialties, University Sapienza Rome, Rome, Italy
| | - Paola Matarrese
- Department of Drug Research and Evaluation, Istituto Superiore di Sanit, à, Rome, Italy
- Center of Metabolomics, Rome, Italy
| | - Marilia Carabotti
- Department of Internal Medicine and Medical Specialties, University Sapienza Rome, Rome, Italy
| | - Barbara Ascione
- Department of Drug Research and Evaluation, Istituto Superiore di Sanit, à, Rome, Italy
| | - Walter Malorni
- Department of Drug Research and Evaluation, Istituto Superiore di Sanit, à, Rome, Italy
- San Raffaele Pisana Institute, Rome, Italy
| | - Carola Severi
- Department of Internal Medicine and Medical Specialties, University Sapienza Rome, Rome, Italy
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26
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Loss of serum response factor induces microRNA-mediated apoptosis in intestinal smooth muscle cells. Cell Death Dis 2015; 6:e2011. [PMID: 26633717 PMCID: PMC4720888 DOI: 10.1038/cddis.2015.353] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2015] [Revised: 10/29/2015] [Accepted: 11/05/2015] [Indexed: 01/12/2023]
Abstract
Serum response factor (SRF) is a transcription factor known to mediate phenotypic plasticity in smooth muscle cells (SMCs). Despite the critical role of this protein in mediating intestinal injury response, little is known about the mechanism through which SRF alters SMC behavior. Here, we provide compelling evidence for the involvement of SRF-dependent microRNAs (miRNAs) in the regulation of SMC apoptosis. We generated SMC-restricted Srf inducible knockout (KO) mice and observed both severe degeneration of SMCs and a significant decrease in the expression of apoptosis-associated miRNAs. The absence of these miRNAs was associated with overexpression of apoptotic proteins, and we observed a high level of SMC death and myopathy in the intestinal muscle layers. These data provide a compelling new model that implicates SMC degeneration via anti-apoptotic miRNA deficiency caused by lack of SRF in gastrointestinal motility disorders.
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27
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Park C, Lee MY, Park PJ, Ha SE, Berent RM, Fuchs R, Miano JM, Becker LS, Sanders KM, Ro S. Serum Response Factor Is Essential for Prenatal Gastrointestinal Smooth Muscle Development and Maintenance of Differentiated Phenotype. J Neurogastroenterol Motil 2015; 21:589-602. [PMID: 26424044 PMCID: PMC4622142 DOI: 10.5056/jnm15063] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 06/20/2015] [Accepted: 07/12/2015] [Indexed: 12/28/2022] Open
Abstract
Background/Aims Smooth muscle cells (SMCs) characteristically express serum response factor (SRF), which regulates their development. The role of SRF in SMC plasticity in the pathophysiological conditions of gastrointestinal (GI) tract is less characterized. Methods We generated SMC-specific Srf knockout mice and characterized the prenatally lethal phenotype using ultrasound biomicroscopy and histological analysis. We used small bowel partial obstruction surgeries and primary cell culture using cell-specific enhanced green fluorescent protein (EGFP) mouse lines to study phenotypic and molecular changes of SMCs by immunofluorescence, Western blotting, and quantitative polymerase chain reaction. Finally we examined SRF change in human rectal prolapse tissue by immunofluorescence. Results Congenital SMC-specific Srf knockout mice died before birth and displayed severe GI and cardiac defects. Partial obstruction resulted in an overall increase in SRF protein expression. However, individual SMCs appeared to gradually lose SRF in the hypertrophic muscle. Cells expressing low levels of SRF also expressed low levels of platelet-derived growth factor receptor alpha (PDGFRαlow) and Ki67. SMCs grown in culture recaptured the phenotypic switch from differentiated SMCs to proliferative PDGFRαlow cells. The immediate and dramatic reduction of Srf and Myh11 mRNA expression confirmed the phenotypic change. Human rectal prolapse tissue also demonstrated significant loss of SRF expression. Conclusions SRF expression in SMCs is essential for prenatal development of the GI tract and heart. Following partial obstruction, SMCs down-regulate SRF to transition into proliferative PDGFRαlow cells that may represent a phenotype responsible for their plasticity. These findings demonstrate that SRF also plays a critical role in the remodeling process following GI injury.
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Affiliation(s)
- Chanjae Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Moon Young Lee
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA.,Department of Physiology, Wonkwang Digestive Disease Research Institute and Institute of Wonkwang Medical Science, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do, Korea
| | - Paul J Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Se Eun Ha
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Robyn M Berent
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Robert Fuchs
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Joseph M Miano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, USA
| | - Laren S Becker
- Gastroenterology and Hepatology, Stanford University School of Medicine, Stanford, California, USA
| | - Kenton M Sanders
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
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28
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Lee MY, Park C, Berent RM, Park PJ, Fuchs R, Syn H, Chin A, Townsend J, Benson CC, Redelman D, Shen TW, Park JK, Miano JM, Sanders KM, Ro S. Smooth Muscle Cell Genome Browser: Enabling the Identification of Novel Serum Response Factor Target Genes. PLoS One 2015; 10:e0133751. [PMID: 26241044 PMCID: PMC4524680 DOI: 10.1371/journal.pone.0133751] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 06/30/2015] [Indexed: 11/18/2022] Open
Abstract
Genome-scale expression data on the absolute numbers of gene isoforms offers essential clues in cellular functions and biological processes. Smooth muscle cells (SMCs) perform a unique contractile function through expression of specific genes controlled by serum response factor (SRF), a transcription factor that binds to DNA sites known as the CArG boxes. To identify SRF-regulated genes specifically expressed in SMCs, we isolated SMC populations from mouse small intestine and colon, obtained their transcriptomes, and constructed an interactive SMC genome and CArGome browser. To our knowledge, this is the first online resource that provides a comprehensive library of all genetic transcripts expressed in primary SMCs. The browser also serves as the first genome-wide map of SRF binding sites. The browser analysis revealed novel SMC-specific transcriptional variants and SRF target genes, which provided new and unique insights into the cellular and biological functions of the cells in gastrointestinal (GI) physiology. The SRF target genes in SMCs, which were discovered in silico, were confirmed by proteomic analysis of SMC-specific Srf knockout mice. Our genome browser offers a new perspective into the alternative expression of genes in the context of SRF binding sites in SMCs and provides a valuable reference for future functional studies.
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Affiliation(s)
- Moon Young Lee
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- Department of Physiology, Wonkwang Digestive Disease Research Institute and Institute of Wonkwang Medical Science, School of Medicine, Wonkwang University, Iksan, Jeollabuk-do, Korea
| | - Chanjae Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Robyn M. Berent
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Paul J. Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Robert Fuchs
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Hannah Syn
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Albert Chin
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Jared Townsend
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Craig C. Benson
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Doug Redelman
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Tsai-wei Shen
- LC Sciences, 2575 West Bellfort Street Suite 270, Houston, Texas, United States of America
| | - Jong Kun Park
- Division of Biological Science, Wonkwang University, Iksan, Jeollabuk-do, South Korea
| | - Joseph M. Miano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, New York, United States of America
| | - Kenton M. Sanders
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- * E-mail:
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29
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MicroRNAs and cardiovascular diseases. BIOMED RESEARCH INTERNATIONAL 2015; 2015:682857. [PMID: 25710020 PMCID: PMC4331324 DOI: 10.1155/2015/682857] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 10/25/2014] [Indexed: 12/19/2022]
Abstract
Coronary artery diseases (CAD) and heart failure have high mortality rate in the world, although much progress has been made in this field in last two decades. There is still a clinical need for a novel diagnostic approach and a therapeutic strategy to decrease the incidence of CAD. MicroRNAs (miRNAs) are highly conserved noncoding small RNA molecules that regulate a large fraction of the genome by binding to complementary messenger RNA sequences, resulting in posttranscriptional gene silencing. Recent studies have shown that specific miRNAs are involved in whole stage of atherosclerosis, from endothelium dysfunction to plaque rupture. These findings suggest that miRNAs are potential biomarkers in early diagnosis and therapeutic targets in CAD. In the present review, we highlight the role of miRNAs in every stage of atherosclerosis, and discuss the prospects of miRNAs in the near future.
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30
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Abstract
Myocardin (MYOCD) is a potent transcriptional coactivator that functions primarily in cardiac muscle and smooth muscle through direct contacts with serum response factor (SRF) over cis elements known as CArG boxes found near a number of genes encoding for contractile, ion channel, cytoskeletal, and calcium handling proteins. Since its discovery more than 10 years ago, new insights have been obtained regarding the diverse isoforms of MYOCD expressed in cells as well as the regulation of MYOCD expression and activity through transcriptional, post-transcriptional, and post-translational processes. Curiously, there are a number of functions associated with MYOCD that appear to be independent of contractile gene expression and the CArG-SRF nucleoprotein complex. Further, perturbations in MYOCD gene expression are associated with an increasing number of diseases including heart failure, cancer, acute vessel disease, and diabetes. This review summarizes the various biological and pathological processes associated with MYOCD and offers perspectives to several challenges and future directions for further study of this formidable transcriptional coactivator.
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Affiliation(s)
- Joseph M Miano
- Aab Cardiovascular Research Institute, University of Rochester School of Medicine and Dentistry, Rochester, NY, USA
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31
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SRF expedites metastasis and modulates the epithelial to mesenchymal transition by regulating miR-199a-5p expression in human gastric cancer. Cell Death Differ 2014; 21:1900-13. [PMID: 25080937 PMCID: PMC4227147 DOI: 10.1038/cdd.2014.109] [Citation(s) in RCA: 78] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2013] [Revised: 06/30/2014] [Accepted: 07/02/2014] [Indexed: 12/26/2022] Open
Abstract
Dysregulation of transcription factors (TFs) is associated with tumor progression, but little is known about TF expression patterns in the context of gastric cancer (GC) metastasis. Using array-based profile analysis, we found that 22 TFs showed differential activities between GC cell lines with low- and high-metastatic potential. Of this group of TFs, serum response factor (SRF) was significantly upregulated in metastatic GC cells. SRF expression was frequently elevated in a panel of metastatic GC cells and tissues, and high-level expression of SRF was significantly associated with a more aggressive phenotype and poor prognosis in patients with GC. In GC cell lines, overexpression of SRF potently promoted cell migration and invasion in vitro as well as the formation of intrahepatic and pulmonary metastases in vivo, whereas loss of SRF inhibited GC cell invasion and metastasis. We also performed a microRNA microarray to screen for transcriptional targets of SRF and found that SRF transactivates miR-199a-5p and miR-199a-3p by directly binding to their promoters. We further determined that overexpression of miR-199a-5p, but not miR-199a-3p, increased GC cell invasion and metastasis. In contrast, inhibition of miR-199a-5p impaired the metastatic potential of GC cells in vitro and in vivo, and E-cadherin was identified as a direct and functional target of miR-199a-5p in GC cells. Specifically, our results showed that SRF promotes GC metastasis and the epithelial to mesenchymal transition (EMT) though miR-199a-5p-mediated downregulation of E-cadherin. The present study thus provides insight into the specific biological behavior of SRF in GC metastasis. As increased activity of the SRF/miR-199a-5p/E-cadherin pathway appears to promote GC cell EMT and metastasis, these regulators may therefore be developed as therapeutic targets or biomarkers for GC progression.
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Sagnol S, Yang Y, Bessin Y, Allemand F, Hapkova I, Notarnicola C, Guichou JF, Faure S, Labesse G, de Santa Barbara P. Homodimerization of RBPMS2 through a new RRM-interaction motif is necessary to control smooth muscle plasticity. Nucleic Acids Res 2014; 42:10173-84. [PMID: 25064856 PMCID: PMC4150794 DOI: 10.1093/nar/gku692] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In vertebrates, smooth muscle cells (SMCs) can reversibly switch between contractile and proliferative phenotypes. This involves various molecular mechanisms to reactivate developmental signaling pathways and induce cell dedifferentiation. The protein RBPMS2 regulates early development and plasticity of digestive SMCs by inhibiting the bone morphogenetic protein pathway through its interaction with NOGGIN mRNA. RBPMS2 contains only one RNA recognition motif (RRM) while this motif is often repeated in tandem or associated with other functional domains in RRM-containing proteins. Herein, we show using an extensive combination of structure/function analyses that RBPMS2 homodimerizes through a particular sequence motif (D-x-K-x-R-E-L-Y-L-L-F: residues 39–51) located in its RRM domain. We also show that this specific motif is conserved among its homologs and paralogs in vertebrates and in its insect and worm orthologs (CPO and MEC-8, respectively) suggesting a conserved molecular mechanism of action. Inhibition of the dimerization process through targeting a conserved leucine inside of this motif abolishes the capacity of RBPMS2 to interact with the translational elongation eEF2 protein, to upregulate NOGGIN mRNA in vivo and to drive SMC dedifferentiation. Our study demonstrates that RBPMS2 possesses an RRM domain harboring both RNA-binding and protein-binding properties and that the newly identified RRM-homodimerization motif is crucial for the function of RBPMS2 at the cell and tissue levels.
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Affiliation(s)
- Sébastien Sagnol
- INSERM U1046, Université Montpellier 1, Université Montpellier 2, 34295 Montpellier, France
| | - Yinshan Yang
- Centre de Biochimie Structurale, CNRS UMR5048, INSERM U1054, Universités Montpellier 1 et 2, 34295 Montpellier, France
| | - Yannick Bessin
- Centre de Biochimie Structurale, CNRS UMR5048, INSERM U1054, Universités Montpellier 1 et 2, 34295 Montpellier, France
| | - Fréderic Allemand
- Centre de Biochimie Structurale, CNRS UMR5048, INSERM U1054, Universités Montpellier 1 et 2, 34295 Montpellier, France
| | - Ilona Hapkova
- INSERM U1046, Université Montpellier 1, Université Montpellier 2, 34295 Montpellier, France
| | - Cécile Notarnicola
- INSERM U1046, Université Montpellier 1, Université Montpellier 2, 34295 Montpellier, France
| | - Jean-François Guichou
- Centre de Biochimie Structurale, CNRS UMR5048, INSERM U1054, Universités Montpellier 1 et 2, 34295 Montpellier, France
| | - Sandrine Faure
- INSERM U1046, Université Montpellier 1, Université Montpellier 2, 34295 Montpellier, France
| | - Gilles Labesse
- Centre de Biochimie Structurale, CNRS UMR5048, INSERM U1054, Universités Montpellier 1 et 2, 34295 Montpellier, France
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Xie L. MKL1/2 and ELK4 co-regulate distinct serum response factor (SRF) transcription programs in macrophages. BMC Genomics 2014; 15:301. [PMID: 24758171 PMCID: PMC4023608 DOI: 10.1186/1471-2164-15-301] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 04/14/2014] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND Serum response factor (SRF) is a widely expressed transcription factor involved in multiple regulatory programs. It is believed that SRF can toggle between disparate programs of gene expression through association with different cofactors. However, the direct evidence as to how these factors function on a genome-wide level is still lacking. RESULTS In the present study, I explored the functions of SRF and its representative cofactors, megakaryoblastic leukemia 1/2 (MKL1/2) and ETS-domain protein 4 (ELK4), during fungal infection challenge in macrophages. The knockdown study, combined with gene expression array analysis, revealed that MKL1/2 regulated SRF-dependent genes were related to actin cytoskeleton organization, while ELK4 regulated SRF-dependent genes were related to external stimulus responses. Subsequent chromatin immunoprecipitation coupled with massively parallel sequencing (ChIP-seq) suggested that many of these regulations were mediated directly in cis. CONCLUSIONS I conclude that SRF utilizes MKL1/2 to fulfill steady state cellular functions, including cytoskeletal organization, and utilizes ELK4 to facilitate acute responses to external infection. Together, these findings indicate that SRF, along with its two cofactors, are important players in both cellular homeostasis and stress responses in macrophages.
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Affiliation(s)
- Lan Xie
- Medical Systems Biology Research Center, Department of Biomedical Engineering, Tsinghua University School of Medicine, Beijing 100084, China.
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Kawakami-Schulz SV, Verdoni AM, Sattler SG, Jessen E, Kao WWY, Ikeda A, Ikeda S. Serum response factor: positive and negative regulation of an epithelial gene expression network in the destrin mutant cornea. Physiol Genomics 2014; 46:277-89. [PMID: 24550211 DOI: 10.1152/physiolgenomics.00126.2013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Increased angiogenesis, inflammation, and proliferation are hallmarks of diseased tissues, and in vivo models of these disease phenotypes can provide insight into disease pathology. Dstn(corn1) mice, deficient for the actin depolymerizing factor destrin (DSTN), display an increase of serum response factor (SRF) that results in epithelial hyperproliferation, inflammation, and neovascularization in the cornea. Previous work demonstrated that conditional ablation of Srf from the corneal epithelium of Dstn(corn1) mice returns the cornea to a wild-type (WT) like state. This result implicated SRF as a major regulator of genes that contributes to abnormal phenotypes in Dstn(corn1) cornea. The purpose of this study is to identify gene networks that are affected by increased expression of Srf in the Dstn(corn1) cornea. Microarray analysis led to characterization of gene expression changes that occur when conditional knockout of Srf rescues mutant phenotypes in the cornea of Dstn(corn1) mice. Comparison of gene expression values from WT, Dstn(corn1) mutant, and Dstn(corn1) rescued cornea identified >400 differentially expressed genes that are downstream from SRF. Srf ablation had a significant effect on genes associated with epithelial cell-cell junctions and regulation of actin dynamics. The majority of genes affected by SRF are downregulated in the Dstn(corn1) mutant cornea, suggesting that increased SRF negatively affects transcription of SRF gene targets. ChIP-seq analysis on Dstn(corn1) mutant and WT tissue revealed that, despite being present in higher abundance, SRF binding is significantly decreased in the Dstn(corn1) mutant cornea. This study uses a unique model combining genetic and genomic approaches to identify genes that are regulated by SRF. These findings expand current understanding of the role of SRF in both normal and abnormal tissue homeostasis.
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Findlay VJ, LaRue AC, Turner DP, Watson PM, Watson DK. Understanding the role of ETS-mediated gene regulation in complex biological processes. Adv Cancer Res 2014; 119:1-61. [PMID: 23870508 DOI: 10.1016/b978-0-12-407190-2.00001-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Ets factors are members of one of the largest families of evolutionarily conserved transcription factors, regulating critical functions in normal cell homeostasis, which when perturbed contribute to tumor progression. The well-documented alterations in ETS factor expression and function during cancer progression result in pleiotropic effects manifested by the downstream effect on their target genes. Multiple ETS factors bind to the same regulatory sites present on target genes, suggesting redundant or competitive functions. The anti- and prometastatic signatures obtained by examining specific ETS regulatory networks will significantly improve our ability to accurately predict tumor progression and advance our understanding of gene regulation in cancer. Coordination of multiple ETS gene functions also mediates interactions between tumor and stromal cells and thus contributes to the cancer phenotype. As such, these new insights may provide a novel view of the ETS gene family as well as a focal point for studying the complex biological control involved in tumor progression. One of the goals of molecular biology is to elucidate the mechanisms that contribute to the development and progression of cancer. Such an understanding of the molecular basis of cancer will provide new possibilities for: (1) earlier detection, as well as better diagnosis and staging of disease; (2) detection of minimal residual disease recurrences and evaluation of response to therapy; (3) prevention; and (4) novel treatment strategies. Increased understanding of ETS-regulated biological pathways will directly impact these areas.
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Affiliation(s)
- Victoria J Findlay
- Department of Pathology and Laboratory Medicine, Hollings Cancer Center, Medical University of South Carolina, Charleston, South Carolina, USA
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Reho JJ, Zheng X, Fisher SA. Smooth muscle contractile diversity in the control of regional circulations. Am J Physiol Heart Circ Physiol 2013; 306:H163-72. [PMID: 24186099 DOI: 10.1152/ajpheart.00493.2013] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Each regional circulation has unique requirements for blood flow and thus unique mechanisms by which it is regulated. In this review we consider the role of smooth muscle contractile diversity in determining the unique properties of selected regional circulations and its potential influence on drug targeting in disease. Functionally smooth muscle diversity can be dichotomized into fast versus slow contractile gene programs, giving rise to phasic versus tonic smooth muscle phenotypes, respectively. Large conduit vessel smooth muscle is of the tonic phenotype; in contrast, there is great smooth muscle contractile diversity in the other parts of the vascular system. In the renal circulation, afferent and efferent arterioles are arranged in series and determine glomerular filtration rate. The afferent arteriole has features of phasic smooth muscle, whereas the efferent arteriole has features of tonic smooth muscle. In the splanchnic circulation, the portal vein and hepatic artery are arranged in parallel and supply blood for detoxification and metabolism to the liver. Unique features of this circulation include the hepatic-arterial buffer response to regulate blood flow and the phasic contractile properties of the portal vein. Unique features of the pulmonary circulation include the low vascular resistance and hypoxic pulmonary vasoconstriction, the latter attribute inherent to the smooth muscle cells but the mechanism uncertain. We consider how these unique properties may allow for selective drug targeting of regional circulations for therapeutic benefit and point out gaps in our knowledge and areas in need of further investigation.
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Affiliation(s)
- John J Reho
- Division of Cardiology, School of Medicine, University of Maryland, Baltimore, Maryland
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Talasila A, Yu H, Ackers-Johnson M, Bot M, van Berkel T, Bennett MR, Bot I, Sinha S. Myocardin regulates vascular response to injury through miR-24/-29a and platelet-derived growth factor receptor-β. Arterioscler Thromb Vasc Biol 2013; 33:2355-65. [PMID: 23825366 DOI: 10.1161/atvbaha.112.301000] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Myocardin, a potent transcriptional coactivator of serum response factor, is involved in vascular development and promotes a contractile smooth muscle phenotype. Myocardin levels are reduced during vascular injury, in association with phenotypic switching of smooth muscle cells (SMCs). However, the direct role of myocardin in vascular disease is unclear. APPROACH AND RESULTS We show that re-expression of myocardin prevents the vascular injury response in murine carotid arteries, with reduced neointima formation due to decreased SMC migration and proliferation. Myocardin reduced SMC migration by downregulating platelet-derived growth factor receptor-β (PDGFRB) expression. Pdgfrb was regulated by myocardin-induced miR-24 and miR-29a expression, and antagonizing these microRNAs restored SMC migration. Furthermore, using miR-24 and miR-29a mimics, we demonstrated that miR-29a directly regulates Pdgfrb expression at the 3' untranslated region while miR-24 has an indirect effect on Pdgfrb levels. Myocardin heterozygous-null mice showed an augmented neointima formation with increased SMC migration and proliferation, demonstrating that endogenous levels of myocardin are a critical regulator of vessel injury responses. CONCLUSIONS Our results extend the function of myocardin from a developmental role to a pivotal regulator of SMC phenotype in response to injury, and this transcriptional coactivator may be an attractive target for novel therapeutic strategies in vascular disease.
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Affiliation(s)
- Amarnath Talasila
- From the Division of Cardiovascular Medicine, University of Cambridge, Addenbrooke's Centre for Clinical Investigation, Addenbrooke's Hospital, Cambridge, United Kingdom (A.T., H.Y., M.A.-J., M.R.B., S.S.); and Division of Biopharmaceutics, Leiden/Amsterdam Centre for Drug Research, Leiden University, Einsteinweg, Leiden, The Netherlands (M.R.B., T.v.B., I.B.)
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Sanders KM, Koh SD, Ro S, Ward SM. Regulation of gastrointestinal motility--insights from smooth muscle biology. Nat Rev Gastroenterol Hepatol 2012; 9:633-45. [PMID: 22965426 PMCID: PMC4793911 DOI: 10.1038/nrgastro.2012.168] [Citation(s) in RCA: 270] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Gastrointestinal motility results from coordinated contractions of the tunica muscularis, the muscular layers of the alimentary canal. Throughout most of the gastrointestinal tract, smooth muscles are organized into two layers of circularly or longitudinally oriented muscle bundles. Smooth muscle cells form electrical and mechanical junctions between cells that facilitate coordination of contractions. Excitation-contraction coupling occurs by Ca(2+) entry via ion channels in the plasma membrane, leading to a rise in intracellular Ca(2+). Ca(2+) binding to calmodulin activates myosin light chain kinase; subsequent phosphorylation of myosin initiates cross-bridge cycling. Myosin phosphatase dephosphorylates myosin to relax muscles, and a process known as Ca(2+) sensitization regulates the activity of the phosphatase. Gastrointestinal smooth muscles are 'autonomous' and generate spontaneous electrical activity (slow waves) that does not depend upon input from nerves. Intrinsic pacemaker activity comes from interstitial cells of Cajal, which are electrically coupled to smooth muscle cells. Patterns of contractile activity in gastrointestinal muscles are determined by inputs from enteric motor neurons that innervate smooth muscle cells and interstitial cells. Here we provide an overview of the cells and mechanisms that generate smooth muscle contractile behaviour and gastrointestinal motility.
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Abstract
BACKGROUND Inflammation-induced changes in smooth muscle may be the consequence of changes in the properties of smooth muscle itself, in the control by nerves and hormones, in the microenvironment, or in the balance of constitutive or induced mediators. A general concept is that the specific characteristics and effects of inflammation can be linked to the nature of the infiltrate and the associated mediators, which are dictated predominantly by the immune environment. Inflammatory mediators may regulate smooth muscle function by directly acting on smooth muscle cells or, indirectly, through stimulation of the release of mediators from other cells. In addition, smooth muscle is not a passive bystander during inflammation and our knowledge of molecular signaling pathways that control smooth muscle function, and the contribution of the immune mechanisms to smooth muscle homeostasis, has expanded greatly in the last decade. Recent studies also demonstrated the relevance of extracellular proteases, of endogenous or exogenous origin, redox imbalance, or epigenetic mechanisms, to gastrointestinal dismotility and inflammation in the context of functional and organic disorders. PURPOSE In this review we discuss the various types of inflammation and the established and emerging mechansims of inflammation-induced changes in smooth muscle morphology and function.
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Affiliation(s)
- T Shea-Donohue
- Mucosal Biology Research Center and Department of Medicine, University of Maryland School of Medicine, Baltimore, MD 21201, USA.
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Joshi SR, McLendon JM, Comer BS, Gerthoffer WT. MicroRNAs-control of essential genes: Implications for pulmonary vascular disease. Pulm Circ 2012; 1:357-64. [PMID: 22140625 PMCID: PMC3224427 DOI: 10.4103/2045-8932.87301] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
During normal lung development and in lung diseases structural cells in the lungs adapt to permit changes in lung function. Fibroblasts, myofibroblasts, smooth muscle, epithelial cells, and various progenitor cells can all undergo phenotypic modulation. In the pulmonary vasculature occlusive vascular lesions that occur in severe pulmonary arterial hypertension are multifocal, polyclonal lesions containing cells presumed to have undergone phenotypic transition resulting in altered proliferation, cell lifespan or contractility. Dynamic changes in gene expression and protein composition that underlie processes responsible for such cellular plasticity are not fully defined. Advances in molecular biology have shown that multiple classes of ribonucleic acid (RNA) collaborate to establish the set of proteins expressed in a cell. Both coding Messenger Ribonucleic acid (mRNA) and small noncoding RNAs (miRNA) act via multiple parallel signaling pathways to regulate transcription, mRNA processing, mRNA stability, translation and possibly protein lifespan. Rapid progress has been made in describing dynamic features of miRNA expression and miRNA function in some vascular tissues. However posttranscriptional gene silencing by microRNA-mediated mRNA degradation and translational blockade is not as well defined in the pulmonary vasculature. Recent progress in defining miRNAs that modulate vascular cell phenotypes is reviewed to illustrate both functional and therapeutic significance of small noncoding RNAs in pulmonary arterial hypertension.
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Affiliation(s)
- Sachindra R Joshi
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama, USA
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Lerch JK, Kuo F, Motti D, Morris R, Bixby JL, Lemmon VP. Isoform diversity and regulation in peripheral and central neurons revealed through RNA-Seq. PLoS One 2012; 7:e30417. [PMID: 22272348 PMCID: PMC3260295 DOI: 10.1371/journal.pone.0030417] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2011] [Accepted: 12/15/2011] [Indexed: 11/19/2022] Open
Abstract
To fully understand cell type identity and function in the nervous system there is a need to understand neuronal gene expression at the level of isoform diversity. Here we applied Next Generation Sequencing of the transcriptome (RNA-Seq) to purified sensory neurons and cerebellar granular neurons (CGNs) grown on an axonal growth permissive substrate. The goal of the analysis was to uncover neuronal type specific isoforms as a prelude to understanding patterns of gene expression underlying their intrinsic growth abilities. Global gene expression patterns were comparable to those found for other cell types, in that a vast majority of genes were expressed at low abundance. Nearly 18% of gene loci produced more than one transcript. More than 8000 isoforms were differentially expressed, either to different degrees in different neuronal types or uniquely expressed in one or the other. Sensory neurons expressed a larger number of genes and gene isoforms than did CGNs. To begin to understand the mechanisms responsible for the differential gene/isoform expression we identified transcription factor binding sites present specifically in the upstream genomic sequences of differentially expressed isoforms, and analyzed the 3′ untranslated regions (3′ UTRs) for microRNA (miRNA) target sites. Our analysis defines isoform diversity for two neuronal types with diverse axon growth capabilities and begins to elucidate the complex transcriptional landscape in two neuronal populations.
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Affiliation(s)
- Jessica K. Lerch
- The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Frank Kuo
- The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Dario Motti
- The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - Richard Morris
- The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- The Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
| | - John L. Bixby
- The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- The Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- Department of Cellular and Molecular Pharmacology, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- * E-mail: (VPL); (JLB)
| | - Vance P. Lemmon
- The Miami Project to Cure Paralysis, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida, United States of America
- * E-mail: (VPL); (JLB)
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Joshi SR, Comer BS, McLendon JM, Gerthoffer WT. MicroRNA Regulation of Smooth Muscle Phenotype. MOLECULAR AND CELLULAR PHARMACOLOGY 2012; 4:1-16. [PMID: 25309675 PMCID: PMC4190587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Advances in studies of microRNA (miRNA) expression and function in smooth muscles illustrate important effects of small noncoding RNAs on cell proliferation, hypertrophy and differentiation. An emerging theme in miRNA research in a variety of cell types including smooth muscles is that miRNAs regulate protein expression networks to fine tune phenotype. Some widely expressed miRNAs have been described in smooth muscles that regulate important processes in many cell types, such as miR-21 control of proliferation and cell survival. Other miRNAs that are prominent regulators of smooth muscle-restricted gene expression also have targets that control pluripotent cell differentiation. The miR-143~145 cluster which targets myocardin and Kruppel-like factor 4 (KLF4) is arguably the best-described miRNA family in smooth muscles with profound effects on gene expression networks that promote serum response factor (SRF)-dependent contractile and cytoskeletal protein expression and the mature contractile phenotype. Kruppel-family members KLF4 and KLF5 have multiple effects on cell differentiation and are targets for multiple miRNAs in smooth muscles (miR-145, miR-146a, miR-25). The feedback and feedforward loops being defined appear to contribute significantly to vascular and airway remodeling in cardiovascular and respiratory diseases. RNA interference approaches applied to animal models of vascular and respiratory diseases prove that miRNAs and RNA-induced silencing are valid targets for novel anti-remodeling therapies that alter pathological smooth muscle hyperplasia and hypertrophy.
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Affiliation(s)
- Sachindra R Joshi
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama
| | - Brian S Comer
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama
| | - Jared M McLendon
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama
| | - William T Gerthoffer
- Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, Alabama
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Benson CC, Zhou Q, Long X, Miano JM. Identifying functional single nucleotide polymorphisms in the human CArGome. Physiol Genomics 2011; 43:1038-48. [PMID: 21771879 DOI: 10.1152/physiolgenomics.00098.2011] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Regulatory SNPs (rSNPs) reside primarily within the nonprotein coding genome and are thought to disturb normal patterns of gene expression by altering DNA binding of transcription factors. Nevertheless, despite the explosive rise in SNP association studies, there is little information as to the function of rSNPs in human disease. Serum response factor (SRF) is a widely expressed DNA-binding transcription factor that has variable affinity to at least 1,216 permutations of a 10 bp transcription factor binding site (TFBS) known as the CArG box. We developed a robust in silico bioinformatics screening method to evaluate sequences around RefSeq genes for conserved CArG boxes. Utilizing a predetermined phastCons threshold score, we identified 8,252 strand-specific CArGs within an 8 kb window around the transcription start site of 5,213 genes, including all previously defined SRF target genes. We then interrogated this CArG dataset for the presence of previously annotated common polymorphisms. We found a total of 118 unique CArG boxes harboring a SNP within the 10 bp CArG sequence and 1,130 CArG boxes with SNPs located just outside the CArG element. Gel shift and luciferase reporter assays validated SRF binding and functional activity of several new CArG boxes. Importantly, SNPs within or just outside the CArG box often resulted in altered SRF binding and activity. Collectively, these findings demonstrate a powerful approach to computationally define rSNPs in the human CArGome and provide a foundation for similar analyses of other TFBS. Such information may find utility in genetic association studies of human disease where little insight is known regarding the functionality of rSNPs.
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Affiliation(s)
- Craig C Benson
- University of Rochester Medical Center, Rochester, NY, USA
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Long X, Miano JM. Transforming growth factor-beta1 (TGF-beta1) utilizes distinct pathways for the transcriptional activation of microRNA 143/145 in human coronary artery smooth muscle cells. J Biol Chem 2011; 286:30119-29. [PMID: 21712382 DOI: 10.1074/jbc.m111.258814] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
MicroRNA 143/145 (miR143/145) is restricted to adult smooth muscle cell (SMC) lineages and mediates, in part, the expression of several SMC contractile genes. Although the function of miR143/145 has begun to be elucidated, its transcriptional regulation in response to various signaling inputs is poorly understood. In an effort to define a miR signature for SMC differentiation, we screened human coronary artery SMCs for miRs modulated by TGF-β1, a known stimulus for SMC differentiation. Array analysis revealed a number of TGF-β1-induced miRs, including miR143/145. Validation studies showed that TGF-β1 stimulated miR143/145 expression in a dose- and time-dependent manner. We utilized several chemical inhibitors and found that SB203580, a specific inhibitor of p38MAPK, significantly decreased TGF-β1-induced miR143/145 expression. siRNA studies demonstrated that the effect of TGF-β1 on miR143/145 was dependent upon the myocardin and serum response factor transcriptional switch as well as SMAD4. TGF-β1 stimulated a 580-bp human miR143/145 enhancer, and mutagenesis studies revealed a critical role for both a known CArG box and an adjacent SMAD-binding element for full TGF-β1-dependent activation of the enhancer. Chromatin immunoprecipitation assays documented TGF-β1-mediated enrichment of SMAD3 and SMAD4 binding over the enhancer region containing the SMAD-binding element. Pre-miR145 strongly promoted SMC differentiation, whereas an anti-miR145 partially blocked TGF-β1-induced SMC differentiation. These results demonstrate a dual pathway for TGF-β1-induced transcription of miR143/145, thus revealing a novel mechanism underlying TGF-β1-induced human vascular SMC differentiation.
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Affiliation(s)
- Xiaochun Long
- Aab Cardiovascular Research Institute, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, New York 14642, USA.
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Park C, Yan W, Ward SM, Hwang SJ, Wu Q, Hatton WJ, Park JK, Sanders KM, Ro S. MicroRNAs dynamically remodel gastrointestinal smooth muscle cells. PLoS One 2011; 6:e18628. [PMID: 21533178 PMCID: PMC3077387 DOI: 10.1371/journal.pone.0018628] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2010] [Accepted: 03/08/2011] [Indexed: 11/18/2022] Open
Abstract
Smooth muscle cells (SMCs) express a unique set of microRNAs (miRNAs) which regulate and maintain the differentiation state of SMCs. The goal of this study was to investigate the role of miRNAs during the development of gastrointestinal (GI) SMCs in a transgenic animal model. We generated SMC-specific Dicer null animals that express the reporter, green fluorescence protein, in a SMC-specific manner. SMC-specific knockout of Dicer prevented SMC miRNA biogenesis, causing dramatic changes in phenotype, function, and global gene expression in SMCs: the mutant mice developed severe dilation of the intestinal tract associated with the thinning and destruction of the smooth muscle (SM) layers; contractile motility in the mutant intestine was dramatically decreased; and SM contractile genes and transcriptional regulators were extensively down-regulated in the mutant SMCs. Profiling and bioinformatic analyses showed that SMC phenotype is regulated by a complex network of positive and negative feedback by SMC miRNAs, serum response factor (SRF), and other transcriptional factors. Taken together, our data suggest that SMC miRNAs are required for the development and survival of SMCs in the GI tract.
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Affiliation(s)
- Chanjae Park
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Wei Yan
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Sean M. Ward
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Sung Jin Hwang
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Qiuxia Wu
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - William J. Hatton
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Jong Kun Park
- Division of Biological Science, Wonkwang University, Iksan, Chonbuk, South Korea
| | - Kenton M. Sanders
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
| | - Seungil Ro
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, United States of America
- * E-mail:
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