Page 13 - 南京医科大学自然版
P. 13
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