Oligodendroglial expression of TrkB independently regulates myelination and progenitor cell proliferation

Abstract

The neurotrophin brain-derived neurotrophic factor (BDNF) has been implicated in regulating CNS myelination. BDNF mutant mice exhibit a hypomyelinating phenotype, and BDNF exerts distinct effects upon oligodendroglial proliferation, differentiation, and myelination in vitro. To investigate the precise influence that BDNF exerts in regulating CNS myelination in vivo, we have generated conditional knock-out mice in which TrkB has been deleted specifically in oligodendrocytes. Deletion of TrkB disrupted normal oligodendrocyte myelination, resulting in a significant reduction in myelin protein expression and myelination of CNS white matter tracts during development. Importantly, conditional knoc..