E3 (ubiquitin) ligases interact with ubiquitin-E2 (ubiquitin-conjugating) enzymes and the target protein, transferring the ubiquitin from the E2 to the substrate. KCMF1 ubiquitin ligases are defined based on the presence of InterPro domain IPR039858 and their homology to human KCMF1/FIGC.