Fig. 2.

Similar trajectories of molecular events but differential progression of myelination in different brain regions. A, principal component analysis (PCA) of proteome shows a clear separation of S1 from the other two stages and Cere and Olf from the other 4 regions. Brain regions are color coded. Developmental stages are indicated by different shapes. B, bubble heatmap shows GO and KEGG enrichment of upregulated or downregulated proteins from newborn to juvenile or from juvenile to adult in six brain regions (Fisher’s exact test, fc > 1.5, adjusted p < 0.05). All six brain regions show similarly enriched pathways of upregulated proteins in S2 compared with S1. Size and color of dots indicate fold enrichment for that pathway and adjusted p value, respectively. Upregulated pathways in red and downregulated pathways in blue. C, heatmap shows the average levels of myelination stage-specific marker proteins in different brain regions during postnatal development. D, the diagram shows regional differences in the progression of myelination during postnatal development. The myelination progression at specific developmental stage is determined by the average protein levels of oligodendrocyte-lineage cell type markers indicated by colors in (C). The length of the progression bar is determined by the color intensity (above average level between white and red) shown in (C). Cere, cerebellum; GO, gene ontology; KEGG, Kyoto Encyclopedia of Genes and Genomes; Olf, olfactory bulb.