Endosomal E3 ubiquitin-protein ligase that regulates the recycling endosome pathway by mediating ubiquitination of Synaptobrevin (Syb) (PubMed:23353890). Also acts as a regulator of transcytosis in wing imaginal disks by catalyzing ubiquitination of Syb: ubiquitination of Syb promotes transcytosis of wingless (wg) to the basolateral surface (PubMed:26974662). S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N(6)-ubiquitinyl-[acceptor protein]-L-lysine. Protein modification; protein ubiquitination. Larval lethality. Belongs to the Godzilla family.