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The kinase MST4 limits inflammatory responses through direct phosphorylation of the adaptor TRAF6

Nature Immunology volume 16, pages 246257 (2015) | Download Citation



Immune responses need to be tightly controlled to avoid excessive inflammation and prevent unwanted host damage. Here we report that germinal center kinase MST4 responded dynamically to bacterial infection and acted as a negative regulator of inflammation. We found that MST4 directly interacted with and phosphorylated the adaptor TRAF6 to prevent its oligomerization and autoubiquitination. Accordingly, MST4 did not inhibit lipopolysaccharide-induced cytokine production in Traf6−/− embryonic fibroblasts transfected to express a mutant form of TRAF6 that cannot be phosphorylated at positions 463 and 486 (with substitution of alanine for threonine at those positions). Upon developing septic shock, mice in which MST4 was knocked down showed exacerbated inflammation and reduced survival, whereas heterozygous deletion of Traf6 (Traf6+/−) alleviated such deleterious effects. Our findings reveal a mechanism by which TRAF6 is regulated and highlight a role for MST4 in limiting inflammatory responses.

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We thank H. Ji (Shanghai Institute of Biochemistry and Cell Biology) for the pLKO.1-puro backbone; and D. Li, J. Zhou, G. Pei, B. Sun, L. Li, A. Lin and M. Lei for support. Supported by the 973 program of the Ministry of Science and Technology of China (2012CB910204 and 2012CB910200), the National Natural Science Foundation of China (31270808, 31300734, 31470736, 31470868, 31030021 and 81161120542), the Science and Technology Commission of Shanghai Municipality (11JC14140000 and 13ZR1446400), and the “Cross and cooperation in science and technology innovation team” project of the Chinese Academy of Sciences.

Author information

Author notes

    • Shi Jiao
    • , Zhen Zhang
    •  & Chuanchuan Li

    These authors contributed equally to this work.


  1. National Center for Protein Science Shanghai, State Key Laboratory of Cell Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.

    • Shi Jiao
    • , Zhen Zhang
    • , Chuanchuan Li
    • , Min Huang
    • , Zhubing Shi
    • , Yanyan Wang
    • , Xiaomin Song
    • , Heng Liu
    • , Chunyang Li
    • , Min Chen
    • , Wenjia Wang
    • , Yun Zhao
    • , Hongyan Wang
    • , Catherine C L Wong
    • , Chen Wang
    •  & Zhaocai Zhou
  2. State Key Laboratory of Protein and Plant Gene Research, Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, School of Life Sciences, Peking University, Beijing, China.

    • Zhengfan Jiang
  3. Peking University-Tsinghua University Joint Center for Life Sciences, Beijing, China.

    • Zhengfan Jiang
  4. School of Life Science and Technology, ShanghaiTech University, Shanghai, China.

    • Zhaocai Zhou


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S.J., Zhe.Z. and Chuan.L. designed and carried out most of the experiments and analyzed the data; M.H. and C.C.L.W. performed mass spectrometry analysis; Z.S. did the structural modeling; Y.W. and M.C. provided purified proteins. X.S., H.L., Chun.L. and W.W. contributed to data analysis; Zha.Z., Y.Z., Z.J., H.W. and C.W. contributed to experimental design; S.J., X.S. and Zha.Z. wrote the manuscript; and Zha.Z. supervised the project.

Competing interests

Zha.Z. and S.J. have filed a patent (201410705068.X) related to this work, which covers the potential application of MST4 as a biomarker for certain infectious diseases, and possible therapeutics relevant to the MST4 function in macrophages.

Corresponding authors

Correspondence to Chen Wang or Zhaocai Zhou.

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