Gata4(+/-) mice exhibited short PR intervals indicative of accelerated AV conduction, demonstrating that Gata4 is a novel regulator of atrioventricular delay.
This study identifies Gata4 as a novel transcriptional regulator of atrioventricular delay through its action on the Cx30.2 enhancer.
The cardiac conduction system comprises a specialized tract of electrically coupled cardiomyocytes responsible for impulse propagation through the heart. Abnormalities in cardiac conduction are responsible for numerous forms of cardiac arrhythmias, but relatively little is known about the gene regulatory mechanisms that control the formation of the conduction system. We demonstrate that a distal enhancer for the connexin 30.2 (Cx30.2, also known as Gjd3) gene, which encodes a gap junction protein required for normal atrioventricular (AV) delay in mice, is necessary and sufficient to direct expression to the developing AV conduction system (AVCS). Moreover, we show that this enhancer requires Tbx5 and Gata4 for proper expression in the conduction system, and Gata4(+/-) mice have short PR intervals indicative of accelerated AV conduction. Thus, our results implicate Gata4 in conduction system function and provide a clearer understanding of the transcriptional pathways that impact normal AV delay.
Munshi et al. (Fri,) conducted a other in Cardiac conduction abnormalities. Gata4 haploinsufficiency (Gata4+/-) vs. Wild-type was evaluated on PR interval and atrioventricular conduction. Gata4(+/-) mice exhibited short PR intervals indicative of accelerated AV conduction, demonstrating that Gata4 is a novel regulator of atrioventricular delay.