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第44卷第5期             曾   强,张在奎,孙乃双,等. TBK1对NLRC4炎症小体的作用及其机制研究[J].
                  2024年5月                    南京医科大学学报(自然科学版),2024,44(5):595-603,614                     ·601 ·


                A                       B                        C                       D
                           HEK293T                 HEK293T
                  Flag⁃NLRC4  +  +         Myc⁃TBK1  +  +         GST⁃TBK1  +  +            GST⁃TBK1  +  -
                   Myc⁃TBK1  -  +         Flag⁃NLRC4  -  +        HIS⁃NLRC4  -  +           HIS⁃NLRC4  +  +
                       kDa                     kDa                     kDa                       kDa
                       110        Flag          80        Myc           80       TBK1            110       NLRC4
                  IP:Myc                 IP:Flag                 IP:HIS                    IP:GST
                        80        Myc          110        Flag         110       NLRC4            80       TBK1
                       110        Flag          80        Myc           80       TBK1            110       NLRC4
                   Input                   Input                   Input                     Input
                        80        Myc          110        Flag         110       NLRC4            80       TBK1
                E    Flag⁃TBK1    Myc⁃NLRC4     F                   HEK293T         G              HEK293T
                                                          Flag⁃TBK1 - + +  + +           Myc⁃TBK1 +  +  -  -
                                                         Myc⁃NLRC4 + + -  - -          Myc⁃TBK1⁃N -  -  +  -
                                                    Myc⁃NLRC4(LRR) - - +  - -          Myc⁃TBK1⁃C -  -  -  +
                                                  Myc⁃NLRC4(NACHT) - - -  + -           Flag⁃NLRC4 -  +  +  +
                                                  Myc⁃NLRC4(ΔCARD) - - -  - +                kDa
                                                              kDa                             80
                                                                                              55            Myc
                                                               100                     IP:Flag
                                                                              Myc             35
                       DAPI         Merge               IP:Flag  50
                                                                                             110            Flag
                                                               80             Flag
                                                                                              80
                                                               100                            55            Myc
                                                                              Myc
                                                               50                        Input  35
                                                          Input
                                                               80             Flag
                                                                                             110            Flag
                                                               80             TBK1
                H                                                                            1                729
                                 HEK293T                   1              1 025
                                                                                        TBK1    N         C
                       Flag⁃TBK1 -  +  -  -          NLRC4  CARD  NACHT  LRR                 1       309
                 Flag⁃TBK1⁃Ser172D -  -  +  -                141          1 025       TBK1⁃N     N
                 Flag⁃TBK1⁃Ser172A -  -  -  +        ΔCARD       NACHT   LRR                         310      729
                      Myc⁃NLRC4 +  +  +  +                   141       563            TBK1⁃C              C
                                                     NACHT       NACHT
                            kDa
                                                                       564  1 025
                            110            Myc         LRR               LRR
                      IP:Flag
                             80            Flag
                            110            Myc
                       Input
                             80            Flag
                   A,B:The overexpression of Flag⁃NLRC4 and Myc⁃TBK1 was observed in HEK293T cells,and their interactions were detected by co⁃immunopre⁃
                cipitation. C,D:Purified GST⁃TBK1 was incubated with purified HIS⁃NLRC4 for 2 h,and glutathione magnetic beads were used to pull down HIS⁃NLRC4
                with GST⁃TBK1,followed with immunoblotting analysis. E:Flag⁃TBK1 and Myc⁃NLRC4 were overexpressed in HEK293T cells,and the localization was
                detected using anti⁃Flag and anti⁃Myc immunofluorescence staining. The green mark is anti⁃Flag,the red mark is anti⁃Myc,and the blue mark is DAPI
               (Scale bar:20 μm). F:The overexpression of Myc ⁃ NLRC4 or its truncated form Myc ⁃ NLRC4(NACHT,LRR,and ΔCARD)with Flag ⁃ TBK1 in
                HEK293T cells was analyzed by co⁃immunoprecipitation and Western blot. G:Myc⁃TBK1 or its truncated form Myc⁃TBK1(TBK1⁃N,TBK1⁃C)and
                Flag⁃NLRC4 were expressed in HEK293T cells,and their interactions were analyzed by co⁃immunoprecipitation and Western blot. H:The overexpression
                of Flag⁃TBK1 or its mutant Flag⁃TBK1(TBK1⁃Ser172A,TBK1⁃Ser172D)and Myc⁃NLRC4 in HEK293T cells was subjected to co⁃immunoprecipitation
                and Western blot analysis.
                                                   图2 TBK1与NLRC4相互作用
                                                 Figure 2 TBK1 interacts with NLRC4

                化变体),通过免疫沉淀收集 Myc⁃NLRC4 或 Myc⁃                    NLRC4 Ser533位点。
                NLRC4(Ser533A),采用Anti⁃p⁃NLRC4(Ser533)磷酸           2.5  抑制TBK1可提高小鼠防御S.T感染能力
                化抗体检测,结果显示,TBK1 促进 Myc⁃NLRC4 的                        ELISA结果显示,与对照组相比,实验组小鼠的
                Ser533 磷酸化,而阴性对照 Myc⁃NLRC4(Ser533A)               血清及腹腔灌洗液中的IL⁃1β和TNF⁃α含量减少(图
                无信号(图4A)。而且,在HEK293T细胞中分别过量                       5A~D),细菌负荷量也明显降低(图5E、F),差异有统

                表 达 Myc⁃NLRC4、Myc⁃NLRC4(Ser533A)、Myc⁃             计学意义。流式细胞术结果也同样显示实验组小鼠
                NLRC4(Ser533D)(NLRC4 的永久磷酸化变体)和                   腹腔灌洗液中的中性粒细胞(CD11b /Ly6G )比例下
                                                                                                  +
                                                                                                        +
                Flag⁃TBK1,免疫共沉淀和 Western blot 检测表明,               降(图5G、H),实验组小鼠的生存率显著提高(图5I),
                NLRC4 Ser533 位点的磷酸化并不影响其与TBK1的                    差异有统计学意义。以上结果说明抑制TBK1可以
                相互作用(图4B)。以上结果说明,TBK1可以磷酸化                        通过控制NLRC4炎症小体的过度活化,稳定免疫微
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