Deactivation of the kinase IKK by CUEDC2 through recruitment of the phosphatase PP1


Despite rapid progress in elucidating the molecular mechanisms of activation of the kinase IKK, the processes that regulate IKK deactivation are still unknown. Here we demonstrate that CUE domain–containing 2 (CUEDC2) interacted with IKKα and IKKβ and repressed activation of the transcription factor NF-κB by decreasing phosphorylation and activation of IKK. Notably, CUEDC2 also interacted with GADD34, a regulatory subunit of protein phosphatase 1 (PP1). We found that IKK, CUEDC2 and PP1 existed in a complex and that IKK was released from the complex in response to inflammatory stimuli such as tumor necrosis factor. CUEDC2 deactivated IKK by recruiting PP1 to the complex. Therefore, CUEDC2 acts as an adaptor protein to target IKK for dephosphorylation and inactivation by recruiting PP1.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: CUEDC2 binds to IKKα and IKKβ and decreases their phosphorylation.
Figure 2: CUEDC2 inhibits NF-κB activation through IKK inactivation.
Figure 3: CUEDC2 inhibits IKK phosphorylation by interacting with IKK.
Figure 4: IKK transiently disassociates from CUEDC2 but is recruited to TRAF2.
Figure 5: CUEDC2 and GADD34 mediate the formation of a IKK-CUEDC2-GADD34-PP1 complex.
Figure 6: CUEDC2 induces IKK dephosphorylation by recruiting the GADD34-PP1 complex to IKK.
Figure 7: CUEDC2 inhibits TNF-induced gene expression.


  1. 1

    Chen, G. & Goeddel, D.V. TNF-R1 signaling: a beautiful pathway. Science 296, 1634–1635 (2002).

    CAS  Article  Google Scholar 

  2. 2

    Wajant, H., Pfizenmaier, K. & Scheurich, P. Tumor necrosis factor signaling. Cell Death Differ. 10, 45–65 (2003).

    CAS  Article  Google Scholar 

  3. 3

    Karin, M. & Ben-Neriah, Y. Phosphorylation meets ubiquitination: the control of NF-κB activity. Annu. Rev. Immunol. 18, 621–663 (2000).

    CAS  Article  Google Scholar 

  4. 4

    Maniatis, T. A ubiquitin ligase complex essential for the NF-κB, Wnt/Wingless, and Hedgehog signaling pathways. Genes Dev. 13, 505–510 (1999).

    CAS  Article  Google Scholar 

  5. 5

    Häcker, H. & Karin, M. Regulation and function of IKK and IKK-related kinases. Sci. STKE 357, re13 (2006).

    Google Scholar 

  6. 6

    Li, Q., Estepa, G., Memet, S., Israel, A. & Verma, I.M. Complete lack of NF-κB activity in IKK1 and IKK2 double deficient mice: additional defect in neurulation. Genes Dev. 14, 1729–1733 (2000).

    CAS  PubMed  PubMed Central  Google Scholar 

  7. 7

    Ghosh, S. & Karin, M. Missing pieces in the NF-κB puzzle. Cell 109, S81–S96 (2002).

    CAS  Article  Google Scholar 

  8. 8

    Yamaoka, S. et al. Complementation cloning of NEMO, a component of the IκB kinase complex essential for NF-κB activation. Cell 93, 1231–1240 (1998).

    CAS  Article  Google Scholar 

  9. 9

    Delhase, M., Hayakawa, M., Chen, Y. & Karin, M. Positive and negative regulation of IκB kinase activity through IKKβ subunit phosphorylation. Science 284, 309–313 (1999).

    CAS  Article  Google Scholar 

  10. 10

    Mercurio, F. et al. IKK-1 and IKK-2: cytokine-activated IκB kinases essential for NF-κB activation. Science 278, 860–866 (1997).

    CAS  Article  Google Scholar 

  11. 11

    Jackman, J., Alamo, I. & Fornace, A.J. Jr. Genotoxic stress confers preferential and coordinate messenger RNA stability on the five gadd genes. Cancer Res. 54, 5656–5662 (1994).

    CAS  PubMed  Google Scholar 

  12. 12

    Aggen, J.B., Nairn, A.C. & Chamberlin, R. Regulation of protein phosphatase-1. Chem. Biol. 7, R13–R23 (2000).

    CAS  Article  Google Scholar 

  13. 13

    Bollen, M. Combinatorial control of protein phosphatase-1. Trends Biochem. Sci. 26, 426–431 (2001).

    CAS  Article  Google Scholar 

  14. 14

    Egloff, M.P. et al. Structural basis for the recognition of regulatory subunits by the catalytic subunit of protein phosphatase 1. EMBO J. 16, 1876–1887 (1997).

    CAS  Article  Google Scholar 

  15. 15

    Donaldson, K.M., Yin, H., Gekakis, N., Supek, F. & Hoazeiro, C.A. Ubiquitin signals protein trafficking via interaction with a novel ubquitin binding domain in the membrane fusion regulator, Vps9p. Curr. Biol. 13, 258–262 (2003).

    CAS  Article  Google Scholar 

  16. 16

    Ponting, C.P. Proteins of the endoplasmic-retivulum-associated degradation pathway: domain detection and function prediction. Biochem. J. 351, 527–535 (2000).

    CAS  Article  Google Scholar 

  17. 17

    Shih, S.C. et al. A ubiquitin-binding motif required for intramolecular monoubiquitylation, the CUE domain. EMBO J. 22, 1273–1281 (2003).

    CAS  Article  Google Scholar 

  18. 18

    Zhang, P.J. et al. CUE domain containing 2 regulates degradation of progesterone receptor by ubiquitin–proteasome. EMBO J. 26, 1831–1842 (2007).

    CAS  Article  Google Scholar 

  19. 19

    Bender, K., Gottlicher, M., Whiteside, S., Rahmsdorf, H.J. & Herrlich, P. Sequential DNA damage-independent and -dependent activation of NF-κB by UV. EMBO J. 17, 5170–5181 (1998).

    CAS  Article  Google Scholar 

  20. 20

    Li, N. & Karin, M. Ionizing radiation and short wavelength UV activate NF-κB through two distinct mechanisms. Proc. Natl. Acad. Sci. USA 95, 13012–13017 (1998).

    CAS  Article  Google Scholar 

  21. 21

    DiDonato, J.A., Hayakawa, M., Rothwarf, D.M., Zandi, E. & Karin, M. A cytokine-responsive IκB kinase that activates the transcription factor NF-κB. Nature 388, 548–554 (1997).

    CAS  Article  Google Scholar 

  22. 22

    Devin, A. et al. The distinct roles of TRAF2 and RIP in IKK activation by TNF-R1: TRAF2 recruits IKK to TNF-R1 while RIP mediates IKK activation. Immunity 12, 419–429 (2000).

    CAS  Article  Google Scholar 

  23. 23

    Devin, A. et al. The α and β subunits of IκB kinase (IKK) mediate TRAF2-dependent IKK recruitment to tumor necrosis factor (TNF) receptor 1 in response to TNF. Mol. Cell. Biol. 21, 3986–3994 (2001).

    CAS  Article  Google Scholar 

  24. 24

    Naka, T., Nishimoto, N. & Kishimoto, T. The paradigm of IL-6: from basic science to medicine. Arthritis Res. 4, S233–S242 (2002).

    Article  Google Scholar 

  25. 25

    Yang, J. et al. The essential role of MEKK3 in TNF-induced NF-κB activation. Nat. Immunol. 2, 620–624 (2001).

    CAS  Article  Google Scholar 

  26. 26

    Huang, Q. et al. Differential regulation of interleukin 1 receptor and Toll-like receptor signaling by MEKK3. Nat. Immunol. 5, 98–103 (2004).

    CAS  Article  Google Scholar 

  27. 27

    Hsu, H., Huang, J., Shu, H.B., Baichwal, V. & Goeddel, D.V. TNF-dependent recruitment of the protein kinase RIP to the TNF receptor-1 signaling complex. Immunity 4, 387–396 (1996).

    CAS  Article  Google Scholar 

  28. 28

    Nakano, H. et al. Differential regulation of IκB kinase α and β by two upstream kinases, NF-κB-inducing kinase and mitogen-activated protein kinase/ERK kinase kinase-1. Proc. Natl. Acad. Sci. USA 95, 3537–3542 (1998).

    CAS  Article  Google Scholar 

  29. 29

    Brummelkamp, T.R., Nijman, S.M.B., Dirac, A.M.G. & Bernards, R. Loss of the cylindromatosis tumour suppressor inhibits apoptosis by activating NF-κB. Nature 424, 797–801 (2003).

    CAS  Article  Google Scholar 

  30. 30

    Kovalenko, A. et al. The tumour suppressor CYLD negatively regulates NF-κB signaling by deubiquitination. Nature 424, 801–805 (2003).

    CAS  Article  Google Scholar 

  31. 31

    Lee, E.G. et al. Failure to regulate TNF-induced NF-κB and cell death responses in A20-deficient mice. Science 289, 2350–2354 (2000).

    CAS  Article  Google Scholar 

  32. 32

    Trompouki, E. et al. CYLD is a deubiquitinating enzyme that negatively regulates NF-κB activation by TNFR family members. Nature 424, 793–796 (2003).

    CAS  Article  Google Scholar 

  33. 33

    Wertz, I.E. et al. De-ubiquitination and ubiquitin ligase domains of A20 downregulate NF-κB signaling. Nature 430, 694–699 (2004).

    CAS  Article  Google Scholar 

  34. 34

    Jobin, C. & Sartor, R.B. The IκB/NF-κB system: a key determinant of mucosalinflammation and protection. Am. J. Physiol. Cell Physiol. 278, C451–C462 (2000).

    CAS  Article  Google Scholar 

  35. 35

    Li, Q. & Verma, I.M. NF-κB regulation in the immune system. Nat. Rev. Immunol. 2, 725–734 (2002).

    CAS  Article  Google Scholar 

  36. 36

    Prajapati, S.S., Verma, U., Yamamoto, Y.M., Kwak, Y.T. & Gaynor, R.B. Protein phosphatase 2Cβ association with the IκB kinase complex is involved in regulating NF-κB activity. J. Biol. Chem. 279, 1739–1746 (2004).

    CAS  Article  Google Scholar 

  37. 37

    Li, S.T., Wang, L.Y., Berman, M.A., Zhang, Y. & Dorf, M.E. RNAi screen in mouse astrocytes identifies phosphatases that regulate NF-κB signaling. Mol. Cell 24, 497–509 (2006).

    CAS  Article  Google Scholar 

  38. 38

    Man, J.H. et al. PIAS3 induction of PRB sumoylation represses PRB transactivation by destabilizing its retention in the nucleus. Nucleic Acids Res. 34, 5552–5566 (2006).

    CAS  Article  Google Scholar 

  39. 39

    Pan, X. et al. Ubc9 interacts with SOX4 and represses its transcriptional activity. Biochem. Biophys. Res. Commun. 344, 727–734 (2006).

    CAS  Article  Google Scholar 

Download references


We thank Z.G. Liu (National Cancer Institute, National Institutes of Health) for human IKKα and IKKβ plasmids and TRAF2-deficient MEFs; M.W. Mayo (University of Virginia) for the p65 expression plasmid; X. Lin (Anderson Cancer Center) for the RIP expression vector; X.X. Li (Cleveland Clinic Foundation) for construction of pE-selectin-Luc; G. Haegeman (University of Gent, Gent) for the pIL-6-Luc plasmid; and Z.G. Liu for discussions and technical help. Supported by the National Natural Science Foundation of China (30525021, 30672357, 30500583 and 30321003), the Major State Basic Research Development Program of China (973 Program; 2004CB518800) and the National High Technology Research and Development Program of China (2006AA02Z340).

Author information




H.-Y.L., A.-L.L. and X.-M.Z. contributed to all studies; H.L. contributed to the yeast two-hybrid experiments; C.-H.W. and J.-H.M. participated in study design and analyzed data; J.Z., W.-H.L., and X.P. developed the stable cell lines; T.Z. and W.-L.G. contributed to the preparation of antibodies; and Y.-F.G., J.-Y.Z. and P.-J.Z. did the primary macrophage study.

Corresponding authors

Correspondence to Ai-Ling Li or Xue-Min Zhang.

Supplementary information

Supplementary Text and Figures

Supplementary Figures 1–8, Supplementary Table 1 and Supplementary Methods (PDF 465 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Li, HY., Liu, H., Wang, CH. et al. Deactivation of the kinase IKK by CUEDC2 through recruitment of the phosphatase PP1. Nat Immunol 9, 533–541 (2008).

Download citation

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing