The Arf GAP ASAP1 provides a platform to regulate Arf4- and Rab11-Rab8-mediated ciliary receptor targeting.

ABSTRACT: Dysfunctional trafficking to primary cilia is a frequent cause of human diseases known as ciliopathies, yet molecular mechanisms for specific targeting of sensory receptors to cilia are largely unknown. Here, we show that the targeting of ciliary cargo, represented by rhodopsin, is mediated by a specialized system, the principal component of which is the Arf GAP ASAP1. Ablation of ASAP1 abolishes ciliary targeting and causes formation of actin-rich periciliary membrane projections that accumulate mislocalized rhodopsin. We find that ASAP1 serves as a scaffold that brings together the proteins necessary for transport to the cilia including the GTP-binding protein Arf4 and the two G proteins of the Rab family--Rab11 and Rab8--linked by the Rab8 guanine nucleotide exchange factor Rabin8. ASAP

SUBMITTER: Wang J 

PROVIDER: S-EPMC3474927 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature