RAB11 Family Interacting Protein 5 (RAB11FIP5)

RIP11 is important for protein trafficking from AREs to the apical plasma membrane. RIP11 is recruited to AREs by binding to RAB11, as well as through a Mg(2+)-dependent interaction of its C2 domain with neutral phospholipids. The association of RIP11 with membranes is regulated by a phosphorylation and dephosphorylation cycle.

Northern blot analysis detected 2 major RIP11 transcripts of 4.4 and 6 kb. Both transcripts were enriched in kidney, while other tissues expressed reduced levels of RIP11. Antibodies recognized a protein doublet of 72 kD. RIP11 was found to be enriched in polarized epithelial cells where, like Rab11, it localized to subapical recycling endosomes (AREs) and the apical plasma membrane.