Fig. 1: Hic1 identifies a discrete population within the limb mesenchyme.
From: Cellular taxonomy of Hic1+ mesenchymal progenitor derivatives in the limb: from embryo to adult
a Schematic of the experimental strategy for Hic1CreERT2; R26tdTomato genetic recombination. b Maximum intensity projections of whole-mount Hic1CreERT2; R26tdTomato embryos. White-dotted-line outlines the forelimb; red arrowhead highlights tdTomato+ cells within the forelimb. n = 6 embryos from independent litters. Scale bar, 500 µm. c Representative images of Hic1CreERT2; R26tdTomato forelimbs at sequential timepoints. n = 6 embryos from independent litters. Scale bars, 100 µm, 20 µm inset. White box represents inset region, white arrowheads define tdTomato+ cell clusters. d UMAP of aggregated scRNA-seq data representing whole forelimb dissociations (whole 1 and whole 2) and FACS-purified tdTomato+ MPs from E11.5 forelimb buds. e UMAPs of representative genes for each identified cell population: tdTomato+ MPs (Hic1 and Aldh1a2), tdTomato- MPs (Lhx9 and Msx2), myogenic progenitors (Myod1 and Pax7), and epithelium (Krt5 and Krt14). f Maximum intensity projection of E11.5 Hic1CreERT2; R26tdTomato embryo imaged and stained in whole-mount with antibodies against neurofilament heavy chain (NEFH), PAX7, and MF20. n = 3 embryos from independent litters. Scale bars, 500 µm and 100 µm. White box represents inset region highlighted in panel on right, white arrowhead indicates tdTomato+ cells within the limb. g Maximum intensity projection of E12.5 Hic1CreERT2; R26tdTomato embryo stained in whole-mount with antibodies against NEFH, PAX7, and MF20. n = 3 embryos from independent litters. Scale bars, 500 µm and 100 µm. White box represents inset region highlighted in panel on right. Arrowheads indicate clusters of tdTomato+ cells. h Representative immunofluorescence micrographs of E11.5 Hic1CreERT2; R26tdTomato forelimb sections stained with antibodies against NEFH and PAX7. n = 6 embryos from independent litters. Scale bars, 100 µm and 20 µm inset. White box represents inset region highlighted in bottom-right panel. A, anterior; D, distal; Po, posterior; Pr, proximal.
