Small-Molecule Stabilization of 14-3-3 Protein-Protein Interactions Stimulates Axon Regeneration

Neuron. 2017 Mar 8;93(5):1082-1093.e5. doi: 10.1016/j.neuron.2017.02.018.

Abstract

Damaged central nervous system (CNS) neurons have a poor ability to spontaneously regenerate, causing persistent functional deficits after injury. Therapies that stimulate axon growth are needed to repair CNS damage. 14-3-3 adaptors are hub proteins that are attractive targets to manipulate cell signaling. We identify a positive role for 14-3-3s in axon growth and uncover a developmental regulation of the phosphorylation and function of 14-3-3s. We show that fusicoccin-A (FC-A), a small-molecule stabilizer of 14-3-3 protein-protein interactions, stimulates axon growth in vitro and regeneration in vivo. We show that FC-A stabilizes a complex between 14-3-3 and the stress response regulator GCN1, inducing GCN1 turnover and neurite outgrowth. These findings show that 14-3-3 adaptor protein complexes are druggable targets and identify a new class of small molecules that may be further optimized for the repair of CNS damage.

Keywords: 14-3-3; CNS injury; GCN1; GCN2; PPI stabilizer; axon regeneration; fusicoccin; optic nerve; spinal cord injury; stress response.

MeSH terms

  • 14-3-3 Proteins / metabolism*
  • Animals
  • Animals, Newborn
  • Axons / metabolism*
  • Cells, Cultured
  • Glycosides / metabolism*
  • Mice
  • Nerve Regeneration / physiology
  • Rats, Sprague-Dawley
  • Signal Transduction / physiology*

Substances

  • 14-3-3 Proteins
  • Glycosides
  • fusicoccin