Fig. 3. Spatial organization of the embryonic trunk.
a, Schematic of the spatial organization of cell states in the embryonic trunk region at E8.5, and close-up view on the somitogenesis process. b, Schematic and 3D spatial plot of E8.5 (embryo2), showing selected cell states and vISH of Tbx6, Ripply2 and Meox1 in the trunk region. Each dot denotes a bead and the color corresponds to the indicated state. Scale bar, 200 µm. c, UMAP showing beads from E8.5 and E9.5 embryos corresponding to the NMPs, PSM, somites and neural tube states (left) and the corresponding spatial distribution (right) in an E9.5 embryo (array E9.5_2). Each dot denotes a bead and the color corresponds to the indicated state. Scale bar, 100 µm. d, UMAP showing pseudotime analysis along the somitic and neural differentiation trajectories (left) and the corresponding spatial distribution (right) in an E9.5 embryo (array E9.5_2). Each dot denotes a bead and the color corresponds to the assigned pseudotime value. Scale bar, 100 µm. e, Density plot displaying the computed pseudotime difference (y axis) versus the measured spatial distance (x axis) between all beads of the same cell state. Each dot is a pairwise comparison. The dotted line delineates cells with low spatial distance and large transcriptional divergence in the neural tube. f, Spatial plot showing the beads (top) within the dotted line (Fig. 2e) and the distribution of pseudotime values in an E9.5 embryonic trunk (array E9.5_3) that reflects neural tube patterning. Each dot represents a bead. Scale bars, 100 µm.