Fig. 9. A model of Rab clustering during neurite outgrowth.

In response to NGF stimulation, Rab35 (a master Rab) first accumulates at perinuclear Arf6-positive recycling endosomes. Rab35 subsequently recruits MICAL-L1 (a multiple Rab-binding molecule), which functions as a scaffold for Rab8, Rab13, and Rab36 (downstream Rabs). The downstream Rabs recruit their respective effectors, e.g. Rab36 recruits JIP4 to the same compartment, thereby resulting in the concentration of multiple Rab-signalings at the same time.