The differentiation process of OPCs can be divided into early (OPC- iOL) and late (iOL- mOL) stages. OLIG2 recruits BRG1 for chromatin remodeling, which activates gene network required for OPC to iOL transition7. Analyses of two published databases (transcriptomes20 and OLIG2 bind sites7) revealed that, unexpectedly, enhanced olig2 binding also led to also led to repressed gene expression and the number of downregulated genes were comparable with that of upregulated genes (Fig. 1a), which implicates a non-canonical function of OLIG2 in transcriptional inhibition in oligodendrocytes. 50% of the downregulated genes in the early stage were intensively bound with OLIG2, while the ratio decreased to 30% in the late stage (Supplementary Fig. 1a), suggesting that OLIG2 is more dominant for gene repression in early stage. Gene Ontology (GO) analyses showed that downregulated genes with increased OLIG2 binding in early stage are enriched for those that function in cell growth and cell migration (Fig. 1b).
