RAB15 Effector Protein (REP15)

REP15 is a binding partner of the RAB GTPase family member RAB15 that facilitates transferrin receptor (TFRC) recycling from the endocytic recycling compartment.The deduced 233-amino acid protein shares 73.8% identity with the predicted mouse ortholog. By cell fractionation, biochemical, and Western blot analysis, they localized REP15 to endocytic membrane and cytosolic fractions in HeLa cells and suggested that REP15 has membrane-binding properties that involve protein-protein interactions. Confocal microscopy colocalized REP15 and RAB15 to the perinuclear region of HeLa cells. Sucrose gradient cell fractionation and organelle-specific immunoprecipitation experiments showed that REP15 coprecipitated with RAB11 (RAB11A) and TFRC but did not associate with early endosomal marker EEA1.