Single-cell transcriptional profiles of the atrioventricular canal of 1-month-old zebrafish treated with DMSO or IWR-1-endo

To identify the crosstalk between Wnt/β-catenin signaling activated cardiomyocytes (β-cat ON CMs) and coronary endothelial cells (coECs), we performed single-cell RNA sequencing on all the cells of the atrioventricular canal (AVC) at 1 month, which contains newly formed coronary vessels. To identify the extracellular ligands regulated by Wnt/β-catenin signaling, we also collected AVC from fish treated with DMSO or IWR1-endo, an inhibitor of Wnt/β-catenin signaling. Our analyses indicated that Fgf and/or Sema signaling are potential candidates for mediating the crosstalk between β-cat ON CMs and coECs. We treated 1-month-old Tg(cryaa:EGFP, myl7:GAL4db-TCFΔC);(5xUAS:NTR-mCherry) fish with DMSO or 10 μM IWR1-endo for 48 hours. Hearts were resected from the fish treated with MTZ or DMSO, respectively. We isolated AVCs from hearts and dissociated them into single cells. Barcoded single-cell cDNA libraries were prepared using the Chromium Next GEM single cell 3’reagent kits v3.1 and sequenced using Illumina NextSeq 500.