Molecular cause of the differential activity of Sox8 and Sox10 in oligodendroglial cells

Oligodendroglial cells are responsible for the generation of myelin sheaths in the central nervous system and thereby render rapid saltatory conduction possible. During development, oligodendroglial cells express the three paralogous transcription factors Sox8, Sox9 and Sox10. In mature oligodendrocytes Sox8 and Sox10 expression persists. Whereas Sox9 and Sox10 fulfill important regulatory roles in these cells, Sox8 has only a limited impact on oligodendroglial development and myelination. By replacing Sox10 with Sox8 or Sox9 in the oligodendroglial Oln93 cell line and by comparing expression profiles, we show that Sox8 regulates the same processes as Sox10 and Sox9, but has a substantially lower transcriptional activity under standard culture conditions. Overall design: To identify differential activity of Sox8 and Sox10 in oligodendroglia, we transduced genome-edited Oln93 cells that lack Sox10 with lentiviruses containing GFP and mouse coding sequences for Sox8, Sox9 or Sox10. Transduced GFP-postive cells were purified by fluorescence activated cell-sorting and used for RNA preparation. RNA-Seq was performed with the isolated total RNA and comparative gene expression profiles were generated.