Regulates ADAM17 protease, a sheddase of the epidermal growth factor (EGF) receptor ligands and TNF, thereby plays a role in sleep, cell survival, proliferation, migration and inflammation. Does not exhibit any protease activity on its own. Homodimer, or homooligomer. Interacts with TGFA and HBEGF (By similarity). Interacts with EGF; may retain EGF in the endoplasmic reticulum and regulates its degradation through the endoplasmic reticulum-associated degradation (ERAD) (PubMed:21439629). Interacts (via cytoplasmic N-terminus) with FRMD8/iTAP; this interaction leads to mutual protein stabilization (By similarity). Interacts with ADAM17/TACE (By similarity). Predominantly localized in the endoplasmic reticulum membrane. Expressed in the duodenum, as well as in fetal liver and head. Belongs to the peptidase S54 family. Truncated N-terminus. Extended N-terminus.