IKKα、β、ε及TBK1在CD154诱导转录因子NF-κB活化中的作用  

IKKα,β,εand TBK1 in CD154-induced NF-κB activation

作　　者：张烜[1] 张文[1] 张奉春[1] 

机构地区：[1]中国医学科学院中国协和医科大学北京协和医院风湿免疫科,北京100730

出　　处：《中华微生物学和免疫学杂志》2006年第8期680-683,共4页Chinese Journal of Microbiology and Immunology

基　　金：2005-07年教育部新世纪优秀人才支持计划(NCET-04-0191);国家自然科学基金(30400410);北京市自然科学基金(7052052)

摘　　要：目的研究IκB上游激酶IKK在CD40配体CD154诱导NF-κB活化中的作用机制以及与构架蛋白TRAF的相关性。方法应用重组CD154刺激EBV／LMP1阴性Ramos B细胞,研究IKK质粒转染表达对NF-κB luciferase活化的影响,并通过IKK免疫复合物激酶试验测定IKK对GST-IκB-α磷酸化活性以及免疫共沉淀试验判断IKK与TRAF的相互关系。结果IKKα/β、IKKε和TBK1活性在CD154刺激5-15 min内达到高峰;抗IKKα磁珠可以免疫共沉淀IKKβ,反之亦然。而抗IKKε或TBK1磁珠不能共沉淀其他3种IKK;CD154刺激诱导TRAF2与IKKε和TBK1,TRAF5与TBK1共沉淀增加,而TANK与TBK1共沉淀减少。IKKα或IKKβ并不与TANK或任何TRAF共沉淀。结论CD154刺激诱导IKKα、β、ε及TBK1活化,并诱导TRAF2与IKKε和TBK1结合,TRAF5与TBK1结合,而TANK与TBK1逐渐解离。IKKα/β激酶复合物位于IKKε和TBK1的下游。Objective To investigate the role of IKKs in CD154-induced NF-κB activation and their relationship with TRAF family proteins. Methods Using recombinant CD154 to stimulate EBV/LMP1 negative Ramos B cell and to observe the roles of IKKα,β with vectors expressing constitutively active（SS→EE） or kinase dead （K→M） versions of IKKα or IKKβ. Activity of IKK was determined by IKK immunocomplex kinase assay and estimated as the ability to phosphorylate glutathione-S-transferase （GST）-IκB-α. Immunoprecipitation （IP） experiments were performed using specific anti-IKKα、β、ε and TBK1 antibodies conjugated with protein-A beads to examine IKK＇s correlation with TRAF. Results CD154 stimulation on Ramos B cells induced activation of IKKα、β、ε and TBK1, increasing of TRAF2＇s IP with both IKKε and TBK1, TRAF5＇s IP with TBK1 and decreasing of TANK＇s IP with TBK1. IKKα/βdid not show any direct IP with TRAF proteins. Conclusion CD154 stimulation on Ramos B eells induces activation of IKKα、β、ε and TBK1, TRAF2 association with both IKKε and TBK1, TRAF5 association with TBK1 but TANK dissociation from TBK1. IKKα/β lie in downstream of this signal pathway.

关 键 词：IKK TRAF CD154 NF-ΚB 

分 类 号：R392[医药卫生—免疫学]