title: Transcriptional regulation of the sodium channel gene (SCN5A) by GATA4 in human heart.
abstract: Aberrant expression of the sodium channel gene (SCN5A) has been proposed to disrupt cardiac action potential and cause human cardiac arrhythmias, but the mechanisms of SCN5A gene regulation and dysregulation still remain largely unexplored. To gain insight into the transcriptional regulatory networks of SCN5A, we surveyed the promoter and first intronic regions of the SCN5A gene, predicting the presence of several binding sites for GATA transcription factors (TFs). Consistent with this prediction, chromatin immunoprecipitation (ChIP) and sequential ChIP (Re-ChIP) assays show co-occupancy of cardiac GATA TFs GATA4 and GATA5 on promoter and intron 1 SCN5A regions in fresh-frozen human left ventricle samples. Gene reporter experiments show GATA4 and GATA5 synergism in the activation of the SCN5A promoter, and its dependence on predicted GATA binding sites. GATA4 and GATA6 mRNAs are robustly expressed in fresh-frozen human left ventricle samples as measured by highly sensitive droplet digital PCR (ddPCR). GATA5 mRNA is marginally but still clearly detected in the same samples. Importantly, GATA4 mRNA levels are strongly and positively correlated with SCN5A transcript levels in the human heart. Together, our findings uncover a novel mechanism of GATA TFs in the regulation of the SCN5A gene in human heart tissue. Our studies suggest that GATA5 but especially GATA4 are main contributors to SCN5A gene expression, thus providing a new paradigm of SCN5A expression regulation that may shed new light into the understanding of cardiac disease.
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Tarradas
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain; School of Medicine, University of California San Diego, La Jolla, CA 92093-0648, USA.
authors.forename: Mel Lina
authors.initials: ML
authors.lastname: Pinsach-Abuin
authors.affiliation: School of Medicine, University of California San Diego, La Jolla, CA 92093-0648, USA.
authors.forename: Carlos
authors.initials: C
authors.lastname: Mackintosh
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain.
authors.forename: Oriol
authors.initials: O
authors.lastname: Llorà-Batlle
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Pérez-Serra
authors.affiliation: Thorax Institute, Cardiology Department, Hospital Clínic, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer, 08036 Barcelona, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Batlle
authors.affiliation: Thorax Institute, Cardiology Department, Hospital Clínic, University of Barcelona, Institute of Biomedical Research August Pi i Sunyer, 08036 Barcelona, Spain.
authors.forename: Félix
authors.initials: F
authors.lastname: Pérez-Villa
authors.affiliation: Institute for Physiology II, University Hospital, 07743 Jena, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Zimmer
authors.affiliation: School of Medicine, University of California San Diego, La Jolla, CA 92093-0648, USA.
authors.forename: Ivan
authors.initials: I
authors.lastname: Garcia-Bassets
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain; Hospital Universitari Dr. Josep Trueta, 17001 Girona, Spain.
authors.forename: Ramon
authors.initials: R
authors.lastname: Brugada
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain; School of Biological, Biomedical, and Environmental Sciences, University of Hull, HU6 7RX, Hull, UK. Electronic address: p.beltran-alvarez@hull.ac.uk.
authors.forename: Pedro
authors.initials: P
authors.lastname: Beltran-Alvarez
authors.affiliation: Medical Sciences Department, School of Medicine, University of Girona, 17071 Girona, Spain; Institut d'Investigació Biomèdica de Girona, 17190 Salt, Spain. Electronic address: sara.pagans@udg.edu.
authors.forename: Sara
authors.initials: S
authors.lastname: Pagans
mesh_terms: D000818:Animals; D001665:Binding Sites; D002460:Cell Line; D050991:GATA4 Transcription Factor / Q000378:metabolism*; D050992:GATA5 Transcription Factor / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D009154:Mutation; D009206:Myocardium / Q000378:metabolism*; D062554:NAV1.5 Voltage-Gated Sodium Channel / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D051381:Rats; D014158:Transcription, Genetic
chemical_list: D050991:GATA4 Transcription Factor; D050992:GATA5 Transcription Factor; D062554:NAV1.5 Voltage-Gated Sodium Channel; D012333:RNA, Messenger; D034741:RNA, Small Interfering
keywords: Cardiac arrhythmias; GATA4; GATA5; GATA6; SCN5A; Transcriptional regulation