The Josephin (or Machado-Joseph Disease (MJD) domain) sub-family of deubiquitinases are cysteine proteases and that catalyze the removal of ubiquitin from ubiquitin chains and ubiquitinated proteins. They belong to MEROPS family C86. (Adapted from PMID:19626045).
Notes on Group
Only one Josephin deubiquitinase gene has been found in D.mel.