Locus Confined Control of Cardiac Tbx3 Expression (p 432)
van Weerd et al examine the 3D chromatin architecture of the Tbx3/5 locus.
The abundance, location, and timing of the expression of transcription factors such as Tbx3 and Tbx5 are critical for the precise development of the cardiac conduction system. Recently, common variations in genomic sequence surrounding the Tbx3/5 locus have been linked to conduction system anomalies that pose a risk for heart failure and sudden death in humans. To investigate whether this region contains important Tbx3/5 regulatory elements, Weerd et al used a chromatin conformation capturing technique called 4C-seq, which identifies genomic regions that interact with one another in the 3D nuclear environment. Using this technique, they found that both the Tbx3 and Tbx5 promoters interact with DNA sequences upstream and downstream of the genes themselves. But crucially, there was …