Thiol-dependent isopeptidase that recognizes and hydrolyzes the peptide bond at the C-terminal Gly of UFM1, a ubiquitin-like modifier protein bound to a number of target proteins (PubMed:25219498, PubMed:32160526). Does not hydrolyze SUMO1 or ISG15 ubiquitin-like proteins (PubMed:25219498). Through TRIP4 deufmylation may regulate intracellular nuclear receptors transactivation and thereby regulate cell proliferation and differentiation (PubMed:25219498). Interacts with DDRGK1 (By similarity). Interacts with TRIP4; deufmylates TRIP4 (PubMed:25219498). The disease is caused by variants affecting the gene represented in this entry. The disease is caused by variants affecting the gene represented in this entry. Belongs to the peptidase C78 family.