Actin waves are structures rich in filamentous actin (F-actin) that form in the somato-neuritic area and move towards neurite ends. The exact triggers for these waves have been unclear. Using an optogenetic tool (Opto-cytTrkB), researchers found that activating the TrkB receptor near the neurite end initiates actin waves and promotes neurite elongation. This process involves localized TrkB signaling in the distal neurite connecting with Rac1 pathways in the proximal region. Additionally, TrkB activity relocates ankyrinG, a key axonal organizer, causing the neurite to develop axonal properties. These findings suggest that local TrkB activation through Opto-cytTrkB can switch a minor neurite to a major axonal one during neuronal polarization by generating actin waves.-Journal cover design by scapiens

https://www.cell.com/cell-chemical-biology/fulltext/S2451-9456(19)30351-4