E3 ubiquitin-protein ligase that possess E3 ubiquitin ligase activity in vitro and mediates protein monoubiquitination (Ref.10). Triggers the monoubiquitination of phosphorylated BIK1 in response to pathogen-associated molecular pattern (PAMP) detection (Ref.10). May be involved in the early steps of the plant defense signaling pathway (Probable). 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 BIK1. Up-regulated by chitin. The RING-type zinc finger domain mediates binding to an E2 ubiquitin-conjugating enzyme. Belongs to the RING-type zinc finger family. ATL subfamily.