Differential retraction of axonal arbor terminals mediated by microtubule and kinesin motor

Abstract

Neurons can extend branches from a single axon to send signals to multiple target cells. Axonal arbor morphology must be changed to establish and alternate neuronal wiring properly. For this purpose, the elongation and retraction rate of each terminal in a single axonal arbor are differentially regulated. In addition, competitive growth regulation between 2 neighboring branch processes has been observed. The intracellular systems involved in how neurons differentially regulate growth and stability of axonal branches within the same arbor remain largely unknown. Microtubules play critical roles in the formation and maintenance of axonal morphology, and their functions can be differentially regulated in a region-dependent manner within a single cell. Based on our findings, we propose a microtubule-dependent model that contributes to the differential branch growth in axonal arbors.