Eisenia fetidaProtease-III-1 Functions in Both Fibrinolysis and Fibrogenesis

[摘要] The fibrinolytic function of earthworm protease-III-1 (EfP-III-1) has been studied in recent years. Here, we found thatEfP-III-1 acted not only in fibrinogenolysis, but also in fibrogenesis. We have usedEfP-III-1 to hydrolyze fibrinogen, and to activate plasminogen and prothrombin. Based on the N-terminal sequences of the hydrolyticfragments,EfP-III-1 was showed to specifically recognize the carboxylicsites of arginine and lysine. Analyses by fibrinogenolysis mapping and amino acidsequencing revealed that the isozyme could cleave the alpha, beta, and gamma chainsof fibrinogen, showing a highα-fibrinogenase, moderateβ-fibrinogenase, and lowγ-fibrinogenase activities. Interestingly,EfP-III-1 activated plasminogen and released active plasmin, suggesting a tPA-like function. Furthermore,EfP-III-1 showed a factor Xa-like function on prothrombin, producing alpha-thrombin. The function in both activating prothrombinand catalyzing fibrinogenolysis suggests thatEfP-III-1 may playa role in the balance between procoagulation and anticoagulation.

[学科分类] 基础医学