brefeldin-resistant Arf-GEF 2 protein BRAG2 GEP100 IQ motif and SEC7 domain-containing protein 1 ADP-ribosylation factors guanine nucleotide-exchange protein 100 epididymis secretory sperm binding protein brefeldin A-resistant ARF-GEF2 IDDSSBA ARF-GEP100 ADP-ribosylation factors guanine nucleotide-exchange protein 2 IQ motif and Sec7 domain 1 ARFGEP100