Fig. 4.

Decoding poststroke oligodendrogenesis: From oligodendrocyte precursor cell proliferation to transcriptomic recovery of oligodendrocytes. (A) UMAP visualization (Left) of oligodendrocyte lineage cells including 924 OLs and 235 OPCs from all young groups and with individual visualizations split by groups. Stacked bar plots (Right) showing the proportions of the major subsets (accounting for >10% in all groups) in each group. (B) UMAP visualization of young OPCs over time, colored by the cell cycle stages inferred by CellCycleScoring R function. Pie charts showing the proportion of cells belonging to different cell cycle stages. (C) Heatmap showing the degree of correlation (Pearson correlation coefficient) between OPC subsets and five stages in oligodendrocyte lineage differentiation reported by Marques et al. (17). (D) Violin plots showing the expression levels of markers for five differentiation stages in OPCs and OLs, as a natural log transformation of the raw count data. (E) Representative images of APC and BrdU immunofluorescence staining on brain sections of mice at 14 d after MCAO. [Scale bar, 1 mm (lower magnification) and 200 μm (higher magnification).] Note that images are purposefully captured at long exposures to view entire range of staining intensities from the noninjured to injured hemisphere; for this reason, background is bright in contralesional tissues. (F) The distribution of OLs on pseudotemporal axes in indicated young groups. Arrowheads, peak of pseudotemporal distribution density. Color-coded bars indicated the positions of OLs on pseudotemporal axes. (G) Line charts (Left) showing seven clusters of genes with distinct temporal kinetics in young groups and the numbers of included genes. Heatmap (Middle) showing the expression levels of top 10 genes for each temporal pattern. Representative predicted functions and genes involved in each cluster are annotated on the right.