extracellular domain (ECD) found in lymphocyte antigen 6D (Ly-6D) and similar proteins
Ly-6D (also called E48 antigen) is a GPI-anchored molecule apparently involved in keratinocyte cell-cell adhesion. It may act as a specification marker at earliest stage specification of lymphocytes between B- and T-cell development. Ly-6D 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).