Hoxa11-lineage cells are found within tendon and enthesis and do not express chondro/osteo differentiation genes in the uninjured limb
(A) SnATAC-seq of TdTomato-expressing cluster MSC:0 in the uninjured limb (n = 1). Genes shown are important in chondrogenesis and osteogenesis. Bars represent mean value of reads.
(B) UMAP plot of cells in the uninjured limb.
(C) UMAP feature plot depicting TdTomato expression in the uninjured limb (top left), violin plot showing TdTomato expression across clusters (top right, from Figure 1C), and cell counts across all clusters (bottom).
(D) Violin plots of genes necessary in differentiation of tenocytes (top), chondrocytes (middle), and osteoblasts (bottom).
(E) Confocal microscopy images of the uninjured hindlimb with tile scan (left) and 63× total zoom inset images of regions of interest (n = 2 mice/antigen of interest, n = 3 images/mouse). Colored boxes in tile show region of inset. Sections were immunolabeled with PDGFRα and SOX9 (bottom). Blue chevrons mark Hoxa11iTom cells co-labeled with specified antibodies. Yellow scale bar, 500 μm; white scale bars, 50 μm.