Cleavage of the serine proteinase plasminogen to form plasmin is the central event in the dissolution of blood clots by the fibrinolytic system.Plasminogen related protein B is encoded by the PLGLB1 and PLGLB2 genes. It may bind to lysine binding sites present in the kringle structures of plasminogen interfering with the binding of fibrin or alpha-2-antiplasmin to plasminogen. Within the fibrinolytic cascade, the serine proteinases urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) activate the proenzyme plasminogen by cleaving plasminogen to form the fibrinolytically active enzyme plasmin. PLGLB2 (plasminogen-like B2), also known as PLGP1, is a 96 amino acid protein that resembles the N-terminal plasminogen activation peptide, which is released from plasminogen during conversion to plasmin.