Protease which deconjugates SUMO1, SUMO2 and SUMO3 from some substrate proteins. Has isopeptidase but not SUMO-processing activity. Desumoylates ZBTB46 (By similarity). Collaborates with UBQLN4 in the export of ubiquitinated proteins from the nucleus to the cytoplasm (By similarity). Homodimer (By similarity). Interacts with UBQLN4; leading to the export of UBQLN4 from the nucleus (By similarity). Shuttles between the nucleus and the cytoplasm; exported from the nucleus in a XPO1/CRM1-dependent manner via its nuclear export signal motifs. Belongs to the DeSI family.