TAB1: a target of triptolide in macrophages.
Triptolide (TP) is a biologically active diterpene triepoxide from the Chinese herb Tripterygium wilfordii Hook f. Here, we identify and explore TAB1 as the binding target of TP in macrophages by using a comprehensive approach combining pull-down assays, in vitro assessments, and pharmaceutical and biological evaluation. We discover that TP inhibits TAK1 kinase activity by interfering with the formation of the TAK1-TAB1 complex, and the binding affinity of TP to TAB1 correlates highly with the inhibitory activity of TP against MAPK pathway activation in macrophages. We also find that the amino acid sequence between positions 373 and 502 of TAB1 is required for TP interaction. Our results suggest that TP could be a selective small-molecule inhibitor of the TAK1-TAB1 complex and that TAB1 could be a potential therapeutic target in inflammatory disease.
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China.
Yan
Y
Lu
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China.
Ya
Y
Zhang
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China.
Long
L
Li
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China.
Xiujing
X
Feng
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China.
Sen
S
Ding
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China.
Wei
W
Zheng
Key Lab of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, China.
Jianxin
J
Li
State Key Laboratory of Pharmaceutical Biotechnology and Model Animal Research Center (MARC), Nanjing University, Nanjing 210093, China. Electronic address: ppshen@nju.edu.cn.
Pingping
P
Shen
D048868:Adaptor Proteins, Signal Transducing / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002460:Cell Line; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004224:Diterpenes / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D004852:Epoxy Compounds / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D007249:Inflammation / Q000378:metabolism; D008070:Lipopolysaccharides / Q000633:toxicity; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D010616:Phenanthrenes / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D011485:Protein Binding; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D029757:Tripterygium / Q000737:chemistry / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D048868:Adaptor Proteins, Signal Transducing; D016207:Cytokines; D004224:Diterpenes; D004852:Epoxy Compounds; D008070:Lipopolysaccharides; D010616:Phenanthrenes; D011994:Recombinant Proteins; C531463:Tab1 protein, mouse; D014409:Tumor Necrosis Factor-alpha; C001899:triptolide