Notch Signaling Controls Generation of Motor Neurons in the Lesioned Spinal Cord of Adult Zebrafish

In mammals, increased Notch signaling is thought to contribute to the lack of neurogenesis after spinal cord injury. This study investigates this in zebrafish, which can regenerate neurons after spinal injuries. The researchers found that the Notch pathway is reactivated in zebrafish after spinal cord injury. However, when they increased Notch activity, it reduced the production of new motor neurons. Conversely, blocking the Notch pathway increased the number of new motor neurons. This suggests that Notch signaling normally inhibits motor neuron regeneration in the zebrafish spinal cord.

• 1
  Notch pathway genes are upregulated after spinal lesion in specific dorsoventral domains around the ventricle, reflecting the dorsoventral polarity of the adult progenitor domains.
• 2
  Overactivation of Notch signaling strongly inhibits the generation of new motor neurons in the lesioned spinal cord of adult zebrafish.
• 3
  Pharmacological inhibition of Notch signaling with DAPT augments progenitor proliferation and motor neuron generation in the lesioned spinal cord.