Single cell RNA-seq of neonatal heart regeneration
The adult mammalian heart has limited capacity for regeneration following injury, whereas the neonatal heart can readily regenerate within a short period after birth. Neonatal heart regeneration is orchestrated by multiple cell types intrinsic to the heart, as well as immune cells that infiltrate the heart after injury. To elucidate the transcriptional responses of the different cellular components of the mouse heart following injury, we performed single cell RNA-sequencing on neonatal hearts at various time points following myocardial infarction, and coupled the results with bulk tissue RNA-sequencing data collected at the same time points. Concomitant single cell ATAC-sequencing exposed underlying dynamics of open chromatin landscapes and regenerative gene regulatory networks of diverse cardiac cell types, and revealed previously unknown mediators of cardiomyocyte proliferation, angiogenesis and fibroblast activation. Together, our data provide a transcriptional basis for neonatal heart regeneration at single cell resolution and suggest new strategies for enhancing cardiac function in response to injury. Overall design: We performed myocardial infarction (MI) or sham surgeries to mouse hearts at postnatal day 1 or day 8. At 1d and 3d post P1 and P8 surgery, ventricle samples below the surgery plane were collected for single cell RNA-Seq.