摘要
Abstract
In the central nervous system,the formation of myelin by oligodendrocytes(OLs)relies on the switch from the polymerization of the actin cytoskeleton to its depolymerization.The molecular mechanisms that trigger this switch have yet to be elucidated.Here,we identified P21-activated kinase 1(PAK1)as a major regulator of actin depolymerization in OLs.Our results demonstrate that PAK1 accumulates in OLs in a kinase-inhibited form,trigger-ing actin disassembly and,consequently,myelin membrane expansion.Remarkably,proteomic analysis of PAK1 binding partners enabled the identification of NF2/Merlin as its endogenous inhibitor.Our findings indicate that Nf2 knockdown in OLs results in PAK1 activation,actin polymerization,and a reduction in OL myelin membrane expan-sion.This effect is rescued by treatment with a PAK1 inhibitor.We also provide evidence that the specific Pak1 loss-of-function in oligodendroglia stimulates the thickening of myelin sheaths in vivo.Overall,our data indicate that the antagonistic actions of PAK1 and NF2/Merlin on the actin cytoskeleton of the OLs are critical for proper my-elin formation.These findings have broad mechanistic and therapeutic implications in demyelinating diseases and neurodevelopmental disorders.关键词
NF2/Merlin/P21活化激酶1/肌动蛋白细胞骨架/膜/髓鞘/少突胶质细胞Key words
NF2/Merlin/PAK1/actin cytoskeleton/membrane/myelin/oligodendrocyte分类
医药卫生
