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Kempton A, Cefalu M, Justice C, Baich T, Derbala M, Canan B, Janssen PML, Mohler PJ, Smith SA. Altered regulation of cardiac ankyrin repeat protein in heart failure. Heliyon 2018; 4:e00514. [PMID: 29560432 PMCID: PMC5857524 DOI: 10.1016/j.heliyon.2018.e00514] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 12/22/2017] [Accepted: 01/11/2018] [Indexed: 11/17/2022] Open
Abstract
Background Left ventricular assist devices (LVADs) have revolutionized and improved the care of the sickest heart failure (HF) patients, and it is imperative that they receive appropriate ventricular unloading. Assessing this critical parameter with current methodologies (labs, imaging) is usually suboptimal in this patient population. Hence it is imperative to elucidate the molecular underpinnings involved in ventricular unloading. We have previously identified the cytoskeletal protein βII spectrin as an essential nodal protein involved in post-translational targeting and βII spectrin protein levels are significantly altered in multiple forms of human and animal HF. We therefore hypothesized that the βII spectrin pathway would play a critical role in LVAD remodeling. Methods Human heart failure samples were obtained from patients undergoing heart transplantation. Wild type (WT) mice and our previously validated βII spectrin conditional knock out (βII cKO) mice were used for animal experiments. Transaortic constriction (TAC) was performed on WT mice. Protein expression was assessed via immunoblots, and protein interactions were assessed with co-immunoprecipitation. Transcriptome analysis was performed using isolated whole hearts from control adult WT mice (n = 3) compared to βII cKO spectrin mice (n = 3). Results We report that hearts from mice selectively lacking βII spectrin expression in cardiomyocytes displayed altered transcriptional regulation of cardiac ankyrin repeat protein (CARP). Notably, CARP protein expression is increased after TAC. Additionally, our findings illustrate that prior to LVAD support, CARP levels are elevated in HF patients compared to normal healthy controls. Further, for the first time in a LVAD population, we show that elevated CARP levels in HF patients return to normal following LVAD support. Conclusion Our findings illustrate that CARP is a dynamic molecule that responds to reduced afterload and stress, and has the potential to serve as a prognostic biomarker to assess for an adequate response to LVAD therapy.
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Affiliation(s)
- Amber Kempton
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Matt Cefalu
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Cody Justice
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Tesla Baich
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Mohamed Derbala
- Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Benjamin Canan
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA
| | - Paul M L Janssen
- Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA
| | - Peter J Mohler
- Department of Internal Medicine (Division of Cardiology), The Ohio State University College of Medicine, Columbus, OH, USA.,Department of Physiology and Cell Biology, The Ohio State University, Columbus, OH, USA.,Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
| | - Sakima A Smith
- Department of Internal Medicine (Division of Cardiology), The Ohio State University College of Medicine, Columbus, OH, USA.,Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH, USA
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2
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Ankyrin Repeat Domain 1 Protein: A Functionally Pleiotropic Protein with Cardiac Biomarker Potential. Int J Mol Sci 2017; 18:ijms18071362. [PMID: 28672880 PMCID: PMC5535855 DOI: 10.3390/ijms18071362] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Revised: 06/20/2017] [Accepted: 06/21/2017] [Indexed: 12/20/2022] Open
Abstract
The ankyrin repeat domain 1 (ANKRD1) protein is a cardiac-specific stress-response protein that is part of the muscle ankyrin repeat protein family. ANKRD1 is functionally pleiotropic, playing pivotal roles in transcriptional regulation, sarcomere assembly and mechano-sensing in the heart. Importantly, cardiac ANKRD1 has been shown to be highly induced in various cardiomyopathies and in heart failure, although it is still unclear what impact this may have on the pathophysiology of heart failure. This review aims at highlighting the known properties, functions and regulation of ANKRD1, with focus on the underlying mechanisms that may be involved. The current views on the actions of ANKRD1 in cardiovascular disease and its utility as a candidate cardiac biomarker with diagnostic and/or prognostic potential are also discussed. More studies of ANKRD1 are warranted to obtain deeper functional insights into this molecule to allow assessment of its potential clinical applications as a diagnostic or prognostic marker and/or as a possible therapeutic target.
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3
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Zhang N, Xie XJ, Wang JA. Multifunctional protein: cardiac ankyrin repeat protein. J Zhejiang Univ Sci B 2017; 17:333-41. [PMID: 27143260 DOI: 10.1631/jzus.b1500247] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Cardiac ankyrin repeat protein (CARP) not only serves as an important component of muscle sarcomere in the cytoplasm, but also acts as a transcription co-factor in the nucleus. Previous studies have demonstrated that CARP is up-regulated in some cardiovascular disorders and muscle diseases; however, its role in these diseases remains controversial now. In this review, we will discuss the continued progress in the research related to CARP, including its discovery, structure, and the role it plays in cardiac development and heart diseases.
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Affiliation(s)
- Na Zhang
- Cardiovascular Key Lab of Zhejiang Province, Department of Cardiology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
| | - Xiao-Jie Xie
- Cardiovascular Key Lab of Zhejiang Province, Department of Cardiology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
| | - Jian-An Wang
- Cardiovascular Key Lab of Zhejiang Province, Department of Cardiology, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
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4
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Lun AS, Chen J, Lange S. Probing muscle ankyrin-repeat protein (MARP) structure and function. Anat Rec (Hoboken) 2015; 297:1615-29. [PMID: 25125175 DOI: 10.1002/ar.22968] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 01/02/2014] [Indexed: 12/20/2022]
Abstract
Muscle ankyrin-repeat proteins (MARPs) have been shown to serve diverse functions within cardiac and skeletal muscle cells. Apart from their interactions with sarcomeric proteins like titin or myopalladin that locate them along myofilaments, MARPs are able to shuttle to the nucleus where they act as modulators for a variety of transcription factors. The deregulation of MARPs in many cardiac and skeletal myopathies contributes to their use as biomarkers for these diseases. Many of their functions are attributed to their domain composition. MARPs consist of an N-terminal coiled-coil domain responsible for their dimerization. The C-terminus contains a series of ankyrin repeats, whose best-characterized function is to bind to the N2A region of the giant sarcomeric protein titin. Here we investigate the nature of their dimerization and their interaction with titin more closely. We demonstrate that the coiled-coil domain in all MARPs enables their homo- and hetero-dimerization in antiparallel fashion. Protein complementation experiments indicate further antiparallel binding of the ankyrin repeats to titin's N2A region. Binding of MARP to titin also affects its PKA mediated phosphorylation. We demonstrate further that MARPs themselves are phosphorylated by PKA and PKC, potentially altering their structure or function. These studies elucidate structural relationships within the stretch-responsive MARP/titin complex in cross-striated muscle cells, and may relate to disease relevant posttranslational modifications of MARPs and titin that alter muscle compliance.
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5
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Samaras SE, Almodóvar-García K, Wu N, Yu F, Davidson JM. Global deletion of Ankrd1 results in a wound-healing phenotype associated with dermal fibroblast dysfunction. THE AMERICAN JOURNAL OF PATHOLOGY 2014; 185:96-109. [PMID: 25452119 DOI: 10.1016/j.ajpath.2014.09.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 08/14/2014] [Accepted: 09/19/2014] [Indexed: 12/27/2022]
Abstract
The expression of ankyrin repeat domain protein 1 (Ankrd1), a transcriptional cofactor and sarcomeric component, is strongly elevated by wounding and tissue injury. We developed a conditional Ankrd1(fl/fl) mouse, performed global deletion with Sox2-cre, and assessed the role of this protein in cutaneous wound healing. Although global deletion of Ankrd1 did not affect mouse viability or development, Ankrd1(-/-) mice had at least two significant wound-healing phenotypes: extensive necrosis of ischemic skin flaps, which was reversed by adenoviral expression of ANKRD1, and delayed excisional wound closure, which was characterized by decreased contraction and reduced granulation tissue thickness. Skin fibroblasts isolated from Ankrd1(-/-) mice did not spread or migrate on collagen- or fibronectin-coated surfaces as efficiently as fibroblasts isolated from Ankrd1(fl/fl) mice. More important, Ankrd1(-/-) fibroblasts failed to contract three-dimensional floating collagen gels. Reconstitution of ANKRD1 by adenoviral infection stimulated both collagen gel contraction and actin fiber organization. These in vitro data were consistent with in vivo wound closure studies, and suggest that ANKRD1 is important for the proper interaction of fibroblasts with a compliant collagenous matrix both in vitro and in vivo.
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Affiliation(s)
- Susan E Samaras
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Karinna Almodóvar-García
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Nanjun Wu
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Fang Yu
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee
| | - Jeffrey M Davidson
- Department of Pathology, Microbiology, and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee; Research Service, Veterans Affairs Tennessee Valley Healthcare System, Nashville, Tennessee.
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Ma G, Wang H, Gu X, Li W, Zhang X, Cui L, Li Y, Zhang Y, Zhao B, Li K. CARP, a myostatin-downregulated gene in CFM Cells, is a novel essential positive regulator of myogenesis. Int J Biol Sci 2014; 10:309-20. [PMID: 24644428 PMCID: PMC3957086 DOI: 10.7150/ijbs.7475] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2013] [Accepted: 02/18/2014] [Indexed: 11/30/2022] Open
Abstract
Myostatin, a member of the TGF-β superfamily, has been shown to act as a negative regulator of myogenesis. Although its role in myogenesis has been clearly documented through genetic analysis, few gene cascades that respond to myostatin signaling and regulate myogenesis have been characterized, especially in avian species. In a previous study, we screened for such genes in chicken fetal myoblasts (CFMs) using the differential display PCR method and found that cardiac ankyrin repeat protein (CARP) was downregulated by myostatin and specifically expressed in chicken skeletal muscle. However, little is known about the potential functions of CARP in chicken skeletal myogenesis. In this study, the expression patterns of chicken CARP and the possible function of this gene in skeletal muscle growth were characterized. Our data showed that CARP was predominantly expressed in postnatal skeletal muscle, and its expression increased during myogenic differentiation in CFM cells. When CARP was overexpressed, CFM cell growth was enhanced by accelerating the cell cycle at the G1 to S phase transition and increasing cyclin D1 expression. CARP knockdown had the opposite effect: while myoblasts underwent differentiation, knockdown of CARP expression induced extensive cell death, suppressed the formation of myotubes, and markedly decreased the expression of differentiation-related genes such as myosin heavy chain (MHC), myoD, and caveolin-3. Our findings indicate that CARP may play a key role in the myostatin signaling cascade that governs chicken skeletal myogenesis through promoting proliferation and avoiding apoptosis during CFM cell differentiation.
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Affiliation(s)
- Guoda Ma
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China; ; 2. Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical College, Zhanjiang 524001, China
| | - Haiyang Wang
- 3. Department of General Surgery, First Affiliated Hospital of Harbin Medical University, Harbin 150001, China
| | - Xuefeng Gu
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China
| | - Wen Li
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China
| | - Xingli Zhang
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China
| | - Lili Cui
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China
| | - You Li
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China
| | - Yong Zhang
- 4. National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100005, China
| | - Bin Zhao
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China; ; 2. Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases, Affiliated Hospital of Guangdong Medical College, Zhanjiang 524001, China
| | - Keshen Li
- 1. Institute of Neurology, Guangdong Medical College, Zhanjiang 524001, China
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Torrado M, Franco D, Hernández-Torres F, Crespo-Leiro MG, Iglesias-Gil C, Castro-Beiras A, Mikhailov AT. Pitx2c is reactivated in the failing myocardium and stimulates myf5 expression in cultured cardiomyocytes. PLoS One 2014; 9:e90561. [PMID: 24595098 PMCID: PMC3942452 DOI: 10.1371/journal.pone.0090561] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2013] [Accepted: 02/01/2014] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Pitx2 (paired-like homeodomain 2 transcription factor) is crucial for heart development, but its role in heart failure (HF) remains uncertain. The present study lays the groundwork implicating Pitx2 signalling in different modalities of HF. METHODOLOGY/PRINCIPAL FINDINGS A variety of molecular, cell-based, biochemical, and immunochemical assays were used to evaluate: (1) Pitx2c expression in the porcine model of diastolic HF (DHF) and in patients with systolic HF (SHF) due to dilated and ischemic cardiomyopathy, and (2) molecular consequences of Pitx2c expression manipulation in cardiomyocytes in vitro. In pigs, the expression of Pitx2c, physiologically downregulated in the postnatal heart, is significantly re-activated in left ventricular (LV) failing myocardium which, in turn, is associated with increased expression of a restrictive set of Pitx2 target genes. Among these, Myf5 was identified as the top upregulated gene. In vitro, forced expression of Pitx2c in cardiomyocytes, but not in skeletal myoblasts, activates Myf5 in dose-dependent manner. In addition, we demonstrate that the level of Pitx2c is upregulated in the LV-myocardium of SHF patients. CONCLUSIONS/SIGNIFICANCE The results provide previously unrecognized evidence that Pitx2c is similarly reactivated in postnatal/adult heart at distinct HF phenotypes and suggest that Pitx2c is involved, directly or indirectly, in the regulation of Myf5 expression in cardiomyocytes.
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Affiliation(s)
- Mario Torrado
- Institute of Health Sciences, University of La Coruña, La Coruña, Spain
| | - Diego Franco
- Department of Experimental Biology, University of Jaen, Jaen, Spain
| | | | | | | | - Alfonso Castro-Beiras
- Institute of Health Sciences, University of La Coruña, La Coruña, Spain
- University Hospital Center of La Coruña, La Coruña, Spain
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8
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Ghosh AK, Murphy SB, Kishore R, Vaughan DE. Global gene expression profiling in PAI-1 knockout murine heart and kidney: molecular basis of cardiac-selective fibrosis. PLoS One 2013; 8:e63825. [PMID: 23724005 PMCID: PMC3665822 DOI: 10.1371/journal.pone.0063825] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2012] [Accepted: 04/07/2013] [Indexed: 02/06/2023] Open
Abstract
Fibrosis is defined as an abnormal matrix remodeling due to excessive synthesis and accumulation of extracellular matrix proteins in tissues during wound healing or in response to chemical, mechanical and immunological stresses. At present, there is no effective therapy for organ fibrosis. Previous studies demonstrated that aged plasminogen activator inhibitor-1 (PAI-1) knockout mice develop spontaneously cardiac-selective fibrosis without affecting any other organs. We hypothesized that differential expressions of profibrotic and antifibrotic genes in PAI-1 knockout hearts and unaffected organs lead to cardiac selective fibrosis. In order to address this prediction, we have used a genome-wide gene expression profiling of transcripts derived from aged PAI-1 knockout hearts and kidneys. The variations of global gene expression profiling were compared within four groups: wildtype heart vs. knockout heart; wildtype kidney vs. knockout kidney; knockout heart vs. knockout kidney and wildtype heart vs. wildtype kidney. Analysis of illumina-based microarray data revealed that several genes involved in different biological processes such as immune system processing, response to stress, cytokine signaling, cell proliferation, adhesion, migration, matrix organization and transcriptional regulation were affected in hearts and kidneys by the absence of PAI-1, a potent inhibitor of urokinase and tissue-type plasminogen activator. Importantly, the expressions of a number of genes, involved in profibrotic pathways including Ankrd1, Pi16, Egr1, Scx, Timp1, Timp2, Klf6, Loxl1 and Klotho, were deregulated in PAI-1 knockout hearts compared to wildtype hearts and PAI-1 knockout kidneys. While the levels of Ankrd1, Pi16 and Timp1 proteins were elevated during EndMT, the level of Timp4 protein was decreased. To our knowledge, this is the first comprehensive report on the influence of PAI-1 on global gene expression profiling in the heart and kidney and its implication in fibrogenesis and several other biological processes. The significance of these observations in the light of heart-specific profibrotic signaling and fibrogenesis are discussed.
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Affiliation(s)
- Asish K. Ghosh
- Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Sheila B. Murphy
- Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Raj Kishore
- Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
| | - Douglas E. Vaughan
- Feinberg Cardiovascular Research Institute, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, United States of America
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9
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Torrado M, Iglesias R, Centeno A, López E, Mikhailov AT. Targeted gene-silencing reveals the functional significance of myocardin signaling in the failing heart. PLoS One 2011; 6:e26392. [PMID: 22028870 PMCID: PMC3196561 DOI: 10.1371/journal.pone.0026392] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 09/26/2011] [Indexed: 12/20/2022] Open
Abstract
Background Myocardin (MYOCD), a potent transcriptional coactivator of smooth muscle (SM) and cardiac genes, is upregulated in failing myocardium in animal models and human end-stage heart failure (HF). However, the molecular and functional consequences of myocd upregulation in HF are still unclear. Methodology/Principal Findings The goal of the present study was to investigate if targeted inhibition of upregulated expression of myocd could influence failing heart gene expression and function. To this end, we used the doxorubicin (Dox)-induced diastolic HF (DHF) model in neonatal piglets, in which, as we show, not only myocd but also myocd-dependent SM-marker genes are highly activated in failing left ventricular (LV) myocardium. In this model, intra-myocardial delivery of short-hairpin RNAs, designed to target myocd variants expressed in porcine heart, leads on day 2 post-delivery to: (1) a decrease in the activated expression of myocd and myocd-dependent SM-marker genes in failing myocardium to levels seen in healthy control animals, (2) amelioration of impaired diastolic dysfunction, and (3) higher survival rates of DHF piglets. The posterior restoration of elevated myocd expression (on day 7 post-delivery) led to overexpression of myocd-dependent SM-marker genes in failing LV-myocardium that was associated with a return to altered diastolic function. Conclusions/Significance These data provide the first evidence that a moderate inhibition (e.g., normalization) of the activated MYOCD signaling in the diseased heart may be promising from a therapeutic point of view.
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Affiliation(s)
- Mario Torrado
- Developmental Biology Group, Institute of Health Sciences, University of La Coruña, La Coruña, Spain
| | - Raquel Iglesias
- Developmental Biology Group, Institute of Health Sciences, University of La Coruña, La Coruña, Spain
| | - Alberto Centeno
- Experimental Surgery Unit, University Hospital Center of La Coruña, La Coruña, Spain
| | - Eduardo López
- Experimental Surgery Unit, University Hospital Center of La Coruña, La Coruña, Spain
| | - Alexander T. Mikhailov
- Developmental Biology Group, Institute of Health Sciences, University of La Coruña, La Coruña, Spain
- * E-mail:
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Torrado M, Iglesias R, Centeno A, López E, Mikhailov AT. Exon-skipping brain natriuretic peptide variant is overexpressed in failing myocardium and attenuates brain natriuretic peptide production in vitro. Exp Biol Med (Maywood) 2010; 235:941-51. [DOI: 10.1258/ebm.2010.010078] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Brain natriuretic peptide/natriuretic peptide precursor B (NPPB) is one of the most studied genes in relation to heart failure (HF) conditions. However, it is still unclear as to whether alternative splicing could create NPPB mRNA variants, which may be expressed in normal and diseased myocardium. We aimed to identify and characterize a novel alternatively spliced variant of porcine and human NPPB resulting from exon 2 skipping (designated as ΔE2-NPPB). A variety of conventional molecular, biochemical and immunochemical methods were used to examine the expression and functional consequences of ΔE2-NPPB in vitro and in vivo. The pig ΔE2-NPPB mRNA is effectively translated into stable protein in cell-based assays but, in contrast to normally spliced NPPB, the ΔE2-NPPB protein is not secreted into the media. Co-transfection assays demonstrate that ΔE2-NPPB attenuates production and secretion of normally spliced NPPB, suggesting a negative feedback loop of NPPB signaling through generation of ΔE2-NPPB. The inhibitory effects of ΔE2-NPPB on the expression of NPPB are associated with sequence elements residing in exon 3 of ΔE2-NPPB. In piglets, ΔE2-NPPB gene expression is downregulated in both ventricles after birth, but it is markedly re-activated in the postnatal myocardium in experimental diastolic heart failure. In addition, we demonstrate that the exon-skipped NPPB variants are expressed in the postnatal and adult human myocardium and upregulated at end-stage HF due to dilated cardiomyopathy. Our work uncovers an important role of alternative exon skipping in the regulation of NPPB gene expression, thereby pinpointing a putative new mechanism for post-transcriptional regulation of NPPB production and secretion.
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Affiliation(s)
- Mario Torrado
- Developmental Biology Unit, Institute of Health Sciences, University of La Coruña, Campus de Oza, Building ‘El Fortin’, As Xubias Str. s/n
| | - Raquel Iglesias
- Developmental Biology Unit, Institute of Health Sciences, University of La Coruña, Campus de Oza, Building ‘El Fortin’, As Xubias Str. s/n
| | - Alberto Centeno
- Experimental Surgery Unit, University Hospital Centre of La Coruña, La Coruña 15006, Spain
| | - Eduardo López
- Experimental Surgery Unit, University Hospital Centre of La Coruña, La Coruña 15006, Spain
| | - Alexander T Mikhailov
- Developmental Biology Unit, Institute of Health Sciences, University of La Coruña, Campus de Oza, Building ‘El Fortin’, As Xubias Str. s/n
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Identification of candidate genes potentially relevant to chamber-specific remodeling in postnatal ventricular myocardium. J Biomed Biotechnol 2010; 2010:603159. [PMID: 20368782 PMCID: PMC2846348 DOI: 10.1155/2010/603159] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Accepted: 01/07/2010] [Indexed: 11/18/2022] Open
Abstract
Molecular predisposition of postnatal ventricular myocardium to chamber-dependent (concentric or eccentric) remodeling remains largely elusive. To this end, we compared gene expression in the left (LV) versus right ventricle (RV) in newborn piglets, using a differential display reverse transcription-PCR (DDRT-PCR) technique. Out of more than 5600 DDRT-PCR bands, a total of 153 bands were identified as being differentially displayed. Of these, 96 bands were enriched in the LV, whereas the remaining 57 bands were predominant in the RV. The transcripts, displaying over twofold LV-RV expression differences, were sequenced and identified by BLAST comparison to known mRNA sequences. Among the genes, whose expression was not previously recognized as being chamber-dependent, we identified a small cohort of key regulators of muscle cell growth/proliferation (MAP3K7IP2, MSTN, PHB2, APOBEC3F) and gene expression (PTPLAD1, JMJD1C, CEP290), which may be relevant to the chamber-dependent predisposition of ventricular myocardium to respond differentially to pressure (LV) and volume (RV) overloads after birth. In addition, our data demonstrate chamber-dependent alterations in expression of as yet uncharacterized novel genes, which may also be suitable candidates for association studies in animal models of LV/RV hypertrophy.
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Wei YJ, Cui CJ, Huang YX, Zhang XL, Zhang H, Hu SS. Upregulated expression of cardiac ankyrin repeat protein in human failing hearts due to arrhythmogenic right ventricular cardiomyopathy. Eur J Heart Fail 2009; 11:559-66. [PMID: 19359327 DOI: 10.1093/eurjhf/hfp049] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
AIMS Expression of cardiac ankyrin repeat protein (CARP) is augmented in heart failure due to dilated or ischaemic cardiomyopathy. It is unclear whether CARP is upregulated in heart failure due to arrhythmogenic right ventricular cardiomyopathy (ARVC). In the present study, we investigated the expression pattern of CARP and the correlation between CARP and the well-known heart failure marker pro-atrial natriuretic peptide (proANP) in ARVC failing hearts. METHODS AND RESULTS Gene microarray analysis demonstrated increased CARP expression in ARVC failing hearts compared with non-failing control hearts, which was further validated by real-time RT-PCR, western blot, and ELISA at the mRNA and protein levels. Fractionation experiments revealed that the upregulation of CARP expression is restricted to the nuclei of residual cardiac cells in ARVC failing hearts. Regression analysis showed a positive correlation between CARP and proANP in ARVC failing hearts. CONCLUSION Augmented CARP expression may be a common molecular event in failing hearts regardless of cardiomyopathic aetiology. The upregulation of nuclear CARP expression and positive correlation between cardiac CARP and proANP suggests that CARP may be used as a genetic marker existing in the nuclei in contrast to proANP existing in the cytosol of cardiac cells in heart failure patients.
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Affiliation(s)
- Ying-Jie Wei
- Key Laboratory of Cardiovascular Regenerative Medicine, Chinese Academy of Medical Science, Peking Union Medical College, Fuwai Hospital & Cardiovascular Institute, Ministry of Health, Beijing 100037, People's Republic of China.
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Intron retention generates ANKRD1 splice variants that are co-regulated with the main transcript in normal and failing myocardium. Gene 2009; 440:28-41. [PMID: 19341785 DOI: 10.1016/j.gene.2009.03.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2008] [Revised: 03/13/2009] [Accepted: 03/18/2009] [Indexed: 12/28/2022]
Abstract
The cardiac ankyrin repeat domain 1 protein (ANKRD1, also known as CARP) has been extensively characterized with regard to its proposed functions as a cardio-enriched transcriptional co-factor and stress-inducible myofibrillar protein. The present results show the occurrence of alternative splicing by intron retention events in the pig and human ankrd1 gene. In pig heart, ankrd1 is expressed as four alternatively spliced transcripts, three of which have non-excised introns: ankrd1-contained introns 6, 7 and 8 (i.e., ankrd1-i6,7,8), ankrd1-contained introns 7 and 8 (i.e., ankrd1-i7,8), and ankrd1 retained only intron 8 (i.e., ankrd1-i8). In the human heart, two orthologues of porcine intron-retaining ankrd1 variants (i.e., ankrd1-i8 and ankrd1-i7,8) are detected. We demonstrate that these newly-identified intron-retaining ankrd1 transcripts are functionally intact, efficiently translated into protein in vitro and exported to the cytoplasm in cardiomyocytes in vivo. In the piglet heart, both the intronless and intron-retaining ankrd1 mRNAs are co-expressed in a chamber-dependent manner being more abundant in the left as compared to the right myocardium. Our data further indicate co-upregulation of the ankrd1 spliced variants in myocardium in the porcine model of diastolic heart failure. Most significantly, we demonstrate that in vivo forced expression of recombinant intronless ankrd1 markedly increases the levels of intron-retaining ankrd1 variants (but not of the endogenous main transcript) in piglet myocardium, suggesting that ANKRD1 may positively regulate the expression of its own intron-containing RNAs in response to cardiac stress. Overall, our findings demonstrate that in cardiomyocytes ANKRD1 can exist in multiple isoforms which may contribute to the functional diversity of this factor in heart development and disease.
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