Fig. 2.

Model for ADP-ribosylation factor-like 3 (ARL3) and ARL13B function in regulating the release of lipidated cargoes in the cilium. Myristoylated and prenylated cargoes are carried to the cilium by UNC119 lipid-binding chaperone (UNC119) and phosphodiesterase 6δ (PDE6δ), respectively. Inside the cilium, these cargoes are released by ARL3-GTP that has been activated by cilia-localized ARL13B. Outside the cilium, ARL3 is deactivated by the GTPase-activating protein (GAP) retinitis pigmentosa 2 (RP2).