U4/U6.U5 tri-snRNP-associated protein 2 (USP39)

Plays a role in pre-mRNA splicing as a part of the U4/U6-U5 tri-snRNP, among the building blocks of the spliceosome. Regulates AURKB mRNA levels, and thereby plays a role in cytokinesis and in the spindle checkpoint.

Doesn't have ubiquitin-specific peptidase activity, but could be a rival of ubiquitin C-terminal hydrolases (UCHs). .