Plays an important role in the development of floral organs and chloroplasts (PubMed:30603810). Does not possess deubiquitinating enzyme activity in vitro (PubMed:30603810). Widely expressed with the highest expression in floral organs. Abnormal floral organ and pollen development, and leaf bleaching. Belongs to the peptidase C19 family. Lacks the conserved Cys and His active sites that are essential for the activity of deubiquitinating enzymes. Lacks ubiquitin terminal hydrolase activity.