Deletion of PDK1 in oligodendrocyte lineage cells causes white matter abnormality and myelination defect in the central nervous system

PDK1 (3-Phosphoinositide dependent protein kinase-1) is a member in the PI3K (phosphatidylinositol 3 kinase) pathway and is implicated in neurodevelopmental disease with microcephaly. Although the role of PDK1 in neurogenesis has been broadly studied, it remains unknown how PDK1 may regulate oligogenesis in the central nervous system (CNS). To address this question, we generated oligodendrocyte (OL) lineage cells specific PDK1 conditional knockout (cKO) mice. We find that PDK1 cKOs display abnormal white matter (WM), massive loss of mature OLs and severe defect in myelination in the CNS. In contrast, these mutants exhibit normal neuronal development and unchanged apoptosis in the CNS. We demonstrate that deletion of PDK1 severely impairs OL differentiation. We show that genetic or pharmacological inhibition of PDK1 causes deficit in the mammalian target of rapamycin (mTor) signaling and down-regulation of Sox10. Together, these results highlight a critical role of PDK1 in OL differentiation during postnatal CNS development. •Deletion of PDK1 in oligodendrocyte lineages causes myelination defect and loss of mature OLs in the central nervous system.•Deletion of PDK1 in oligodendrocyte lineages leads to severe impairment in oligodendrocyte differentiation.•Deletion of PDK1 results in down-regulation of Sox10 in the white matter. Pharmacological inhibition of PDK1 significantly reduces Sox10 levels in an oligodendroglial cell line.•PDK1 controls oligodendrocyte differentiation through regulation on the expression of Sox10 and oligodendrocyte-specific genes.