Ubiquitin ligase protein that mediates monoubiquitination of FANCD2 in the presence of UBE2T, a key step in the DNA damage pathway (PubMed:12973351, PubMed:16916645, PubMed:17938197, PubMed:19111657, PubMed:24389026). Also mediates monoubiquitination of FANCI (PubMed:19589784). May stimulate the ubiquitin release from UBE2W. May be required for proper primordial germ cell proliferation in the embryonic stage, whereas it is probably not needed for spermatogonial proliferation after birth. 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. Interacts with GGN (By similarity). Belongs to the multisubunit FA complex composed of FANCA, FANCB, FANCC, FANCE, FANCF, FANCG, FANCL/PHF9 and FANCM (PubMed:12973351, PubMed:15502827, PubMed:16116422, PubMed:22343915). The complex is not found in FA patients. In complex with FANCF, FANCA and FANCG, but not with FANCC, nor FANCE, interacts with HES1; this interaction may be essential for the stability and nuclear localization of FA core complex proteins (PubMed:18550849). Interacts with FANCI (PubMed:21775430). Directly interacts (via the RING-type zinc finger) with UBE2T and UBE2W (PubMed:16916645, PubMed:17938197, PubMed:19111657, PubMed:21775430, PubMed:24389026). The UBC-RWD region (URD) region mediates interaction with FANCI and FANCD2. The RING-type zinc finger domain is monoubiquitinated in the presence of UBE2T and UBE2W. The disease is caused by variants affecting the gene represented in this entry. Although PubMed:12724401 reports that it contains a PHD-type zinc finger, it contains a RING-type zinc finger. Moreover, PHD-type zinc fingers do not have any ubiquitin ligase activity.