Genetic variation in T-box binding element functionally affects SCN5A/SCN10A enhancer.
The contraction pattern of the heart relies on the activation and conduction of the electrical impulse. Perturbations of cardiac conduction have been associated with congenital and acquired arrhythmias as well as cardiac arrest. The pattern of conduction depends on the regulation of heterogeneous gene expression by key transcription factors and transcriptional enhancers. Here, we assessed the genome-wide occupation of conduction system-regulating transcription factors TBX3, NKX2-5, and GATA4 and of enhancer-associated coactivator p300 in the mouse heart, uncovering cardiac enhancers throughout the genome. Many of the enhancers colocalized with ion channel genes repressed by TBX3, including the clustered sodium channel genes Scn5a, essential for cardiac function, and Scn10a. We identified 2 enhancers in the Scn5a/Scn10a locus, which were regulated by TBX3 and its family member and activator, TBX5, and are functionally conserved in humans. We also provided evidence that a SNP in the SCN10A enhancer associated with alterations in cardiac conduction patterns in humans disrupts TBX3/TBX5 binding and reduces the cardiac activity of the enhancer in vivo. Thus, the identification of key regulatory elements for cardiac conduction helps to explain how genetic variants in noncoding regulatory DNA sequences influence the regulation of cardiac conduction and the predisposition for cardiac arrhythmias.
Department of Anatomy, Embryology, and Physiology, Heart Failure Research Center, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Malou
M
van den Boogaard
L Y Elaine
LY
Wong
Federico
F
Tessadori
Martijn L
ML
Bakker
Lisa K
LK
Dreizehnter
Vincent
V
Wakker
Connie R
CR
Bezzina
Peter A C
PA
't Hoen
Jeroen
J
Bakkers
Phil
P
Barnett
Vincent M
VM
Christoffels
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D047369:Chromatin Immunoprecipitation; D016384:Consensus Sequence; D004742:Enhancer Elements, Genetic; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D056426:Genetic Loci; D014644:Genetic Variation; D006329:Heart Conduction System / Q000378:metabolism; D006801:Humans; D008297:Male; D051379:Mice; D008822:Mice, Transgenic; D009206:Myocardium / Q000378:metabolism; D062554:NAV1.5 Voltage-Gated Sodium Channel; D062559:NAV1.8 Voltage-Gated Sodium Channel; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide; D011485:Protein Binding; D017422:Sequence Analysis, DNA; D015222:Sodium Channels / Q000235:genetics*; D020825:T-Box Domain Proteins / Q000378:metabolism; D015027:Zebrafish
D062554:NAV1.5 Voltage-Gated Sodium Channel; D062559:NAV1.8 Voltage-Gated Sodium Channel; C568317:SCN10A protein, human; C568320:SCN5A protein, human; C568318:Scn10a protein, mouse; C568321:Scn5a protein, mouse; D015222:Sodium Channels; D020825:T-Box Domain Proteins; C103172:T-box transcription factor 5; C491460:Tbx3 protein, mouse