Forced Notch Signaling Inhibits Commissural Axon Outgrowth in the Developing Chick Central Nerve System
Authors
Shi, MingLiu, Zhirong
Lv, Yonggang
Zheng, Minhua
Du, Fang
Zhao, Gang
Huang, Ying
Chen, Jiayin
Han, Hua
Ding, Yuqiang
Issue Date
2011-01-21
Metadata
Show full item recordAbstract
Background: A collection of in vitro evidence has demonstrated that Notch signaling plays a key role in the growth of neurites in differentiated neurons. However, the effects of Notch signaling on axon outgrowth in an in vivo condition remain largely unknown.Methodology/Principal Findings: In this study, the neural tubes of HH10-11 chick embryos were in ovo electroporated with various Notch transgenes of activating or inhibiting Notch signaling, and then their effects on commissural axon outgrowth across the floor plate midline in the chick developing central nerve system were investigated. Our results showed that forced expression of Notch intracellular domain, constitutively active form of RBPJ, or full-length Hes1 in the rostral hindbrain, diencephalon and spinal cord at stage HH10-11 significantly inhibited commissural axon outgrowth. On the other hand, inhibition of Notch signaling by ectopically expressing a dominant-negative form of RBPJ promoted commissural axonal growth along the circumferential axis. Further results revealed that these Notch signaling-mediated axon outgrowth defects may be not due to the alteration of axon guidance since commissural axon marker TAG1 was present in the axons in floor plate midline, and also not result from the changes in cell fate determination of commissural neurons since the expression of postmitotic neuron marker Tuj1 and specific commissural markers TAG1 and Pax7 was unchanged.
Conclusions/Significance: We first used an in vivo system to provide evidence that forced Notch signaling negatively regulates commissural axon outgrowth.
Citation
PLoS One. 2011 Jan 21; 6(1):e14570ae974a485f413a2113503eed53cd6c53
10.1371/journal.pone.0014570