Fig. 2: Diverse immature GABAergic neurons within the Arc.
a, Schematic representation of snRNA-seq analysis from the human Arc at GW 30–39. b, Clustering of individual nuclei and visualized by UMAP. Annotation of 15 cell types based on gene expressions (see source data for details). c, The gene expression profile of well-known marker genes is visualized via UMAP. Cells are colored according to gene expression levels (purple, high; gray, low). d, Schematic representations of the dissected regions of the human brain across the trimesters. The primary sites of interneuron generation, MGE, LGE and CGE in the first trimester22. The VZ and neocortical regions in the second trimester25. The Arc and neocortical regions in the third trimester25. e, The cells of human ganglionic eminences (GEs), inhibitory cells of the developing VZ including Arc and developing neocortex are integrated and visualized by UMAP. f, The proportion of the nuclei from cell types across regions (top) and ages (down). g, Sankey diagram illustrating the origins and fates of the immature interneurons in the Arc. h, Left, the pseudotime of interneurons visualized by UMAP. Right, MGE-cortical trajectories (top) and CGE-cortical trajectories (bottom) are inferred from Monocle3. i,j, Left, subpopulations of DCX+ cells in the neonatal human (i) and piglet (j) Arc express different TF enriched in ventral telencephalic origins, immunostained with NKX2.1, LHX6, COUP-TFII and SP8. Right, quantification of DCX+ cells expressing the selected TFs. Two-way unpaired t test (**P = 0.0027, ****P < 0.0001). The data mean ± s.e.m. of counts performed on three individual cases (n = 3) in five independent experiments. Sample size and P values are provided as source data. k, Heatmap of distribution of DCX+ cells expressing different TFs across tiers. The color gradient represents TF expression levels from high (red) to low (blue), as quantified from the counts performed on each species. m, Schematic representation of the spatial distribution of molecularly distinct DCX+ cells in the neonatal human and piglet Arc. TF, transcription factors.
