First published online December 5, 2007
Journal of Cell Science 120, 2405e (2007)
© The Company of Biologists Limited
New tricks: Cdk5 and paxillin in OPC maturation
In the vertebrate nervous system, oligodendrocytes coat axons with multiple layers of myelin, forming a sheath that provides electrical insulation and enables the efficient transmission of action potentials. Before myelin can be produced, oligodendrocyte precursor cells (OPCs) must mature into oligodendrocytes, but the details of this process remain unclear. Now Yuki Miyamoto, Junji Yamauchi and colleagues (p. 4355) demonstrate that cyclin-dependent kinase 5 (Cdk5) and the focal adhesion-associated adaptor protein paxillin are necessary for OPC maturation. Using short hairpin RNAs directed against Cdk5 and paxillin, the authors demonstrate that primary rat OPCs fail to differentiate into oligodendrocytes in the absence of either protein. By co-immunoprecipitation, they show that Cdk5 and paxillin form a complex. Moreover, Cdk5 is shown to phosphorylate paxillin at serine 244 in vitro and within cells, and OPC maturation is inhibited by the overexpression of a mutant form of paxillin that cannot be phosphorylated at residue 244. Together, these results indicate that the phosphorylation of paxillin by Cdk5 is a key event in OPC maturation.
Related articles in JCS:
- Cdk5 regulates differentiation of oligodendrocyte precursor cells through the direct phosphorylation of paxillin
- Yuki Miyamoto, Junji Yamauchi, Jonah R. Chan, Atsumasa Okada, Yasuhiro Tomooka, Shin-ichi Hisanaga, and Akito Tanoue
JCS 2007 120: 4355-4366.
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