extracellular domain (ECD) found in prostate and testis expressed protein 4 (PATE4) and similar proteins
PATE4, also called prostate and testis expressed 4, or PATE-like protein B) is a member of the prostate and testis expression (PATE)-like family of proteins that likely play important roles in reproductive and neuronal physiology. They are expressed mainly in the male genital tract and involved in sperm-oolemma fusion and penetration, but not sperm-zona binding. PATE4 may modulate the function of nicotinic acetylcholine receptors and enhance sperm motility. PATE4 contains an extracellular domain (ECD), which 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).
Jiyao W et al.(2023). "The conserved domain database in 2023.",