E3 ubiquitin-protein ligase able to catalyze polyubiquitination with ubiquitin-conjugating enzyme E2 UBC8, UBC10, UBC11, UBC28 and UBC29 in vitro. 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. The RING-type zinc finger domain mediates binding to an E2 ubiquitin-conjugating enzyme. Belongs to the RING-type zinc finger family. ATL subfamily.