Probable GTPase-activating protein (GAP) for Arf family proteins (Probable). Involved in Golgi apparatus organization by targeting Arf1 to the Golgi, which may be important for membrane trafficking during epithelial morphogenesis (PubMed:27535433). Regulates the positioning of interommatidial precursor cells during compound eye morphogenesis together with Arf6 and Cindr (PubMed:21976699). Required for cleavage furrow ingression in early embryonic cells (PubMed:27535433). Interacts with Cindr. Detected in large puncta at the plasma membrane (PubMed:21976699, PubMed:27535433). Excluded from the nucleus at interphase (PubMed:27535433). Enriched in the nucleus at prometaphase (PubMed:27535433). Expressed in the ectoderm of embryos (at protein level). RNAi-mediated knockdown results in defective compound eye morphogenesis (PubMed:21976699). Maternal RNAi-mediated knockdown results in partial female infertility and, in early embryos, abnormal aggregation of Golgi apparatus and disrupted cleavage furrow ingression (PubMed:27535433). Truncated N-terminus.