Cell Chemical Biology
Volume 26, Issue 12, 19 December 2019, Pages 1652-1663.e4
Journal home page for Cell Chemical Biology

Article
Locally Activating TrkB Receptor Generates Actin Waves and Specifies Axonal Fate

https://doi.org/10.1016/j.chembiol.2019.10.006Get rights and content
Under an Elsevier user license
open archive

Highlights

  • The photoactivatable TrkB receptors initiate actin waves in developing neurons

  • Activated TrkB generates actin waves through the PI3K/AKT pathway

  • Activated TrkB at the neurite end mediates Rac1 signaling from the cell body

  • Local TrkB activation recruits key axonal proteins to the stimulated neurite

Summary

Actin waves are filamentous actin (F-actin)-rich structures that initiate in the somato-neuritic area and move toward neurite ends. The upstream cues that initiate actin waves are poorly understood. Here, using an optogenetic approach (Opto-cytTrkB), we found that local activation of the TrkB receptor around the neurite end initiates actin waves and triggers neurite elongation. During actin wave generation, locally activated TrkB signaling in the distal neurite was functionally connected with preferentially localized Rac1 and its signaling pathways in the proximal region. Moreover, TrkB activity changed the location of ankyrinG––the master organizer of the axonal initial segment-and initiated the stimulated neurite to acquire axonal characteristics. Taken together, these findings suggest that local Opto-cytTrkB activation switches the fate from minor to major axonal neurite during neuronal polarization by generating actin waves.

Keywords

Optogenetics
neuronal polarity
BDNF
TrkB receptor
actin waves
PI3K/AKT
Rac1
Cdc42
AnkyrinG
axonal fate

Cited by (0)

4

These authors contributed equally

5

Lead Contact