Optical Activation of TrkA Signaling

ACS Synth Biol. 2018 Jul 20;7(7):1685-1693. doi: 10.1021/acssynbio.8b00126. Epub 2018 Jul 12.

Abstract

Nerve growth factor/tropomyosin receptor kinase A (NGF/TrkA) signaling plays a key role in neuronal development, function, survival, and growth. The pathway is implicated in neurodegenerative disorders including Alzheimer's disease, chronic pain, inflammation, and cancer. NGF binds the extracellular domain of TrkA, leading to the activation of the receptor's intracellular kinase domain. As TrkA signaling is highly dynamic, mechanistic studies would benefit from a tool with high spatial and temporal resolution. Here we present the design and evaluation of four strategies for light-inducible activation of TrkA in the absence of NGF. Our strategies involve the light-sensitive protein Arabidopsis cryptochrome 2 and its binding partner CIB1. We demonstrate successful recapitulation of native NGF/TrkA functions by optical induction of plasma membrane recruitment and homo-interaction of the intracellular domain of TrkA. This approach activates PI3K/AKT and Raf/ERK signaling pathways, promotes neurite growth in PC12 cells, and supports survival of dorsal root ganglion neurons in the absence of NGF. This ability to activate TrkA using light bestows high spatial and temporal resolution for investigating NGF/TrkA signaling.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Cell Membrane / metabolism
  • Cell Survival / genetics
  • Cell Survival / physiology
  • Ganglia, Spinal / metabolism
  • Nerve Growth Factor / metabolism
  • PC12 Cells
  • Phosphatidylinositol 3-Kinases / genetics
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphorylation / genetics
  • Phosphorylation / physiology
  • Rats
  • Receptor, trkA / genetics
  • Receptor, trkA / metabolism*
  • Signal Transduction

Substances

  • Nerve Growth Factor
  • Phosphatidylinositol 3-Kinases
  • Receptor, trkA