Hearty miR-363 controls HAND1 in cardiac cell specification.

MicroRNAs regulate target gene expression post-transcriptionally in a myriad of cell types and play critical roles in diverse physiological and pathological processes, including cardiomyocyte development, differentiation, and regeneration. The recent publication in Stem Cell Research and Therapy by Wagh and colleagues reports a novel regulatory role for miR-363 in cardiomyocyte specification. By employing microRNA expression profiling and functional knockdown studies on human embryonic stem cell-derived cardiomyocytes, the authors identified miR-363 as an upstream negative regulator of left ventricular specification transcription factor HAND1.