extracellular domain (ECD) found in Acropora millepora threonine-rich protein (TRP) and similar proteins
TRP contains an extracellular domain (ECD) that belongs to Ly-6 antigen/uPA receptor-like (LU) superfamily and exhibits a snake toxin-like fold (also known as three-finger toxin/3FTx fold or three-fingered protein/TFP domain fold).