Involved in retrograde transport of recycling endosomes. Specifically detected in tubulovesicular structures, and colocalizes with TFNR. Highly expressed in brain, retina, heart and kidney. Detected at lower levels in lung, muscle and nerve. Highly expressed at birth and up to day 3; expressed at lower levels in embryo and adult. The PH domain specifically binds phosphatidylserine, which is enriched in recycling endosome membranes, it doesn't recognize PIPs.