Extracellular signal-regulated kinase 5 associates with casein kinase II to regulate GPIb-IX-mediated platelet activation via the PTEN/PI3K/Akt pathway
Extracellular signal-regulated kinase 5 associates with casein kinase II to regulate GPIb-IX-mediated platelet activation via the PTEN/PI3K/Akt pathway
复制标题
细胞外信号调节激酶 5 与酪蛋白激酶 II 结合，通过 PTEN/PI3K/Akt 途径调节 GPIb-IX 介导的血小板活化
DOI：
10.1111/jth.13755
复制
发表时间：
2017-08-01
影响因子：
10.4
通讯作者：
Hu, Y.
中科院分区：
文献类型：
--
作者：
Cheng, Z.;Gao, W.;Hu, Y.
背景：血小板糖蛋白（GP）Ib-IX复合物在血栓形成和止血中发挥重要作用。丝裂原激活蛋白激酶 (MAPK) ERK1/2 和 p38 已被证明在 GPIb-IX 介导的导致整合素激活的信号传导中发挥重要作用。然而，MAPK 细胞外信号调节激酶 5 (ERK5) 在 GPIb-IX 介导的血小板激活中的作用尚不清楚。目的：揭示ERK5在GPIb-IX介导的血小板活化中的功能和机制。方法：在 ERK5 特异性抑制剂存在的情况下，使用 botrocetin/VWF、ristocetin/VWF 或剪切应力下血小板与冯维勒布兰德因子 (VWF) 的粘附来评估 ERK5 在 GPIb-IX 介导的人血小板活化中的功能。 ERK5 相关蛋白从转染 HA 标记 ERK5 的中国仓鼠卵巢 (CHO) 细胞中提取出来，通过质谱法进行鉴定，并在人血小板中得到证实。使用特定抑制剂阐明了 ERK5 相关蛋白在 GPIb-IX 介导的血小板激活中的作用。结果：在 Botrocetin/VWF 或 ristocetin/VWF 刺激的人血小板中，ERK5 的磷酸化水平显着增强。 ERK5抑制剂XMD8-92抑制由botrocetin/VWF或ristocetin/VWF诱导的第二波人血小板聚集，并抑制剪切应力下人血小板在固定化VWF上的粘附。酪蛋白激酶 II (CKII) 被鉴定为人血小板中的 ERK5 相关蛋白。 CKII 抑制剂 TBB 与 ERK5 抑制剂 XMD8-92 类似，可特异性抑制 PTEN 磷酸化，从而抑制 Botrocetin/VWF 处理的人血小板中的 Akt 磷酸化。结论：ERK5 与 CKII 结合，通过 PTEN/PI3K/Akt 途径在 GPIb-IX 介导的血小板激活中发挥重要作用。
Background: The platelet glycoprotein (GP) Ib-IX complex plays essential roles in thrombosis and hemostasis. The mitogen-activated protein kinases (MAPKs) ERK1/2 and p38 have been shown to be important in the GPIb-IX-mediated signaling leading to integrin activation. However, the roles of the MAPK extracellular signal-regulated kinase 5 (ERK5) in GPIb-IX-mediated platelet activation are unknown. Objective: To reveal the function and mechanisms of ERK5 in GPIb-IX-mediated platelet activation. Methods: The functions of ERK5 in GPIb-IX-mediated human platelet activation were assessed using botrocetin/VWF, ristocetin/VWF, or platelet adhesion to von Willebrand factor (VWF) under shear stress in the presence of a specific inhibitor of ERK5. ERK5-associated proteins were pulled down from Chinese hamster ovary (CHO) cells transfected with HA-tagged-ERK5, identified by mass spectrometry, and confirmed in human platelets. Roles of ERK5-associated proteins in GPIb-IX-mediated platelet activation were clarified using specific inhibitors. Results: The phosphorylation levels of ERK5 were significantly enhanced in human platelets stimulated with botrocetin/VWF or ristocetin/VWF. The ERK5 inhibitor XMD8-92 suppressed the second wave of human platelet aggregation induced by botrocetin/VWF or ristocetin/VWF and inhibited human platelet adhesion on immobilized VWF under shear stress. Casein kinase II (CKII) was identified as an ERK5-associated protein in human platelets. The CKII inhibitor TBB, similar to the ERK5 inhibitor XMD8-92, specifically restrained PTEN phosphorylation, therefore suppressing Akt phosphorylation in human platelets treated with botrocetin/VWF. Conclusion: ERK5 associates with CKII to play essential roles in GPIb-IX-mediated platelet activation via the PTEN/PI3K/Akt pathway.