Fig. 3: Pericardial and myocardial precursors are transcriptionally distinct populations.
From: The pericardium forms as a distinct structure during heart formation
A Representative confocal max projection of drl:mCherry;hand2:EGFP double-transgenic embryo at 10 hpf as used for FACS-based isolation of post-gastrulation LPM for 10xGenomics-based single-cell transcriptomics; anterior-posterior axis as indicated. N = 3 independent experiments with three embryos imaged per experiment. B UMAP plot of single-cell transcriptomes of mCherry-sorted 10 hpf drl:mCherry;hand2:EGFP zebrafish embryo cells showing 18 significant cell clusters, colored by identified subpopulation. C, D UMAP plots of key myocardial (C) and pericardial genes (D) expressed across identified cluster identities. Cell representations are colored by scaled expression values using lower and upper 2%-quantiles as boundaries. E Whole-mount hybridization chain reaction (HCR) of representative pericardial/mesothelial genes wt1a, fzd7a, jam2b, twist1a, sfrp5, and fn1a. N = 3 independent experiments with 8–10 embryos per experiment. F Clustering analysis of bulk mRNA-sequenced left ventricle myocardium (Myo) and pericardium (Per) from neonatal rats for genes defining myocardium versus pericardium as identified from the zebrafish-based scRNA-seq analysis in (B). Heatmap bins colored by row-scaled log2-normalized counts; columns (samples) split by tissue type; rows and columns ordered by hierarchical clustering (scaled expression values), sex of sample indicated on top. Scale bar A, B, E 200 μm. Species silhouettes were adapted from the PhyloPic database (https://www.phylopic.org/).
