Together with RGLG1, mediates the ubiquitination and subsequent proteasomal degradation of the target protein PP2CA. Functions as positive regulator of abscisic acid (ABA) signaling through ABA-dependent degradation of PP2CA, a major inhibitor of ABA signaling. 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. Interacts with PP2CA. A number of isoforms are produced. According to EST sequences. N-myristoylated.