整合素αⅡ_bβ_3与血小板信号分子PP125^(FAK)磷酸化

Integrin αⅡ_bβ_3 and phosphorylation of signaling molecular PP125^(FAK) in platelets

目的 :探讨整合素α bβ3与血小板信号分子聚焦粘附激酶 PP12 5 F AK磷酸化的关系。方法 :采用免疫沉淀、SDS- PAGE和 Western blots等方法 ,观察在凝血酶刺激时 3种不同条件 (1正常人血小板 ;2用抗α bβ3单克隆抗体阻断正常血小板 ;3α bβ3缺陷的血小板无力症患者血小板 )下血小板 PP12 5 FAK磷酸化反应。结果 :正常人血小板 PP12 5 F AK发生磷酸化反应 ;α bβ3单抗阻断正常血小板其 PP12 5 FAK磷酸化明显减弱 ,但仍可见微弱磷酸化反应 ;血小板无力症患者血小板 PP12 5 F AK未见磷酸化反应。结论 :PP12 5 F AK磷酸化依赖于血小板活化和 α bβ3结构及功能的完整。整合素 α bβ3介导了血小板外 -内信号传导 ,α bβ3缺陷可影响这种信号传导 ,抗 α bβ3单抗不能完全阻断 PP12 5 F

Objective:To explore the relationship between the integrin αⅡ bβ 3 and phosphorylation of signaling molecular PP125 FAK in platelets.Method:Immunoprecipitation,SDS PAGE and western blots were used to detect the phosphorylation of PP125 FAK in platelets after the stimulation of thrombin in three different conditions(Normal control; αⅡ bβ 3 blocked by McAb in normal platelets and Glanzmann thrombasthenia group).Result:Phosphorylation of PP125 FAK in platelets was found in normal control,but remarkably reduced in McAb blocked group and was absent in Glanzmann thrombasthenia group.Conclusion:Phosphorylation of PP125 FAK in platelet depends on both the activation of platelet and the normal structure and function of αⅡ bβ 3 . αⅡ bβ 3 mediates the outside in signaling in platelets,the defect of αⅡ bβ 3 impaires this signal transduction,the phosphorylation of PP125 FAK could not be completely blocked by using a McAb for αⅡ bβ 3 .