Single-cell RNA sequencing of Drosophila embryonic heart

Single-cell RNA sequencing was performed on embryonic Drosophila heart cells. Analysis of single-cell RNA sequence (scRNA-seq) data at timepoints prior to migration of cardiac progenitor cells through to heart tube closure (embryonic stages 13, 14-early, 14-late, 15 and 16) revealed several interesting findings. We found specification of cardiac cell types takes place early, before stage 13, with biggest changes in transcriptomic profiles detected once cells had settled at the midline for further cardioblast maturation. Throughout development, our data identified multiple cell types, covering cardioblasts and five types of pericardial cells including a neural cardiac cell type. The scRNA-seq data further revealed a combination of first and second heart fields during heart development in fly. Further, we uncovered new cell type-specific markers discerning the different cardiac cell types. And we identified signaling pathways key to heart cell maturation, which are conserved from fly to human. We collected fresh embryonic heart cells from stage 13 to stage16 by FACS and prepared single-cell RNA library according to the manufacturer's protocol (10X Genomics, CA, USA), and samples were sequenced by Illumina HiSeq platform (carried out by Novogene, CA).