FIRE is a 689 amino acid protein that maps to human gene EMR4. FIRE is also known as EGF-like module-containing mucin-like hormone receptor-like 4 and is a member of the the G protein-coupled receptor 2 family, LN-TM7 subfamily. The epidermal growth factor-transmembrane seven (EGF-TM7) family are proteins that express EGF-like domains at their extracellular N-terminus coupled to a classical seven-transmembrane (TM7) cassette. FIRE is believed to mediate the cellular interaction between myeloid cells and beta cells. FIRE is a membrane bound, multi-pass protein that is proteolytically cleaved into two subunits, an extracellular alpha subunit and a seven-transmembrane subunit. FIRE contains one GPS (G protein-coupled receptor proteolytic cleavage site) domain and two EGF (epidermal growth factor)-like domains, the second of which mediates the interaction with the putative ligand.