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Regulated nuclear import of Rel proteins in the Drosophila immune response

Abstract

The Drosophila immune response uses many of the same components as the mammalian innate immune response, including signalling pathways that activate transcription factors of the Rel/NK-κB family1,2,3,4. In response to infection, two Rel proteins, Dif and Dorsal, translocate from the cytoplasm to the nuclei of larval fat-body cells1,2,5. The Toll signalling pathway, which controls dorsal–ventral patterning during Drosophila embryogenesis6, regulates the nuclear import of Dorsal in the immune response2,7, but here we show that the Toll pathway is not required for nuclear import of Dif. Cytoplasmic retention of both Dorsal and Dif depends on Cactus protein; nuclear import of Dorsal and Dif is accompanied by degradation of Cactus. Therefore the two signalling pathways that target Cactus for degradation must discriminate between Cactus–Dorsal and Cactus–Dif complexes. We identified new genes that are required for normal induction of transcription of an antibacterial peptide during the immune response. Mutations in three of these genes prevent nuclear import of Dif in response to infection, and define new components of signalling pathways involving Rel. Mutations in three other genes cause constitutive nuclear localization of Dif; these mutations may block Rel protein activity by a novel mechanism.

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Figure 1: Dorsal and Dif nuclear localization in wild-type larval fat-body cells.
Figure 2: Toll is not required for nuclear localization of Dif.
Figure 3: Mutants that affect diptericin (dipt) expression.
Figure 4: Class I mutants block nuclear localization of Dif and have variable effects on Dorsal.
Figure 5: Class II mutants cause constitutive nuclear localization of Dif.
Figure 6: Signalling pathways that control the nuclear localization of Dif and Dorsal in the fat body in response to bacterial infection.

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References

  1. Ip, Y. T. et al. Dif, a dorsal-related gene that mediates an immune response in Drosophila. Cell 75, 753–763 (1993).

    Article  CAS  Google Scholar 

  2. Lemaitre, B. et al. Functional analysis and regulation of nuclear import of Dorsal during the immune response in Drosophila. EMBO J. 14, 536–545 (1995).

    Article  CAS  Google Scholar 

  3. Dushay, M., Åsling, B. & Hultmark, D. Origins of immunity: Relish, a compound Rel-like gene in the antibacterial defense of Drosophila. Proc. Natl Acad. Sci. USA 93, 10343–10347 (1996).

    Article  ADS  CAS  Google Scholar 

  4. Medzhitov, R., Preston-Hurlburt, P. & Janeway, C. A. Jr Ahuman homologue of Drosophila Toll protein signals activation of adaptive immunity. Nature 388, 394–397 (1997).

    Article  ADS  CAS  Google Scholar 

  5. Reichhart, J.-M. et al. Expression and nuclear translocation of the rel/NF-κB-related morphogen dorsal during the immune response of Drosophila. C. R. Acad. Sci. III 316, 1218–1224 (1993).

    CAS  PubMed  Google Scholar 

  6. Belvin, M. P. & Anderson, K. V. Aconserved signaling pathway: The Drosophila Toll-Dorsal Pathway. Annu. Rev. Cell Dev. Biol. 12, 393–416 (1996).

    Article  CAS  Google Scholar 

  7. Lemaitre, B., Nicolas, E., Michaut, L., Reichhardt, J.-M. & Hoffmann, J. A. The dorsoventral regulatory gene cassette spätzle/Toll/cactus controls the potent antifungal response in Drosophila adults. Cell 86, 973–983 (1996).

    Article  CAS  Google Scholar 

  8. Geisler, R., Bergmann, A., Hiromi, Y. & Nüsslein-Volhard, C. cactus, a gene involved in dorsoventral pattern formation of Drosophila, is related to the IκB gene family of vertebrates. Cell 71, 613–621 (1992).

    Article  CAS  Google Scholar 

  9. Kidd, S. Characterization of the Drosophila cactus locus and analysis of interactions between cactus and dorsal proteins. Cell 71, 623–635 (1992).

    Article  CAS  Google Scholar 

  10. Roth, S., Stein, D. & Nüsslein-Volhard, C. Agradient of nuclear localization of the dorsal protein determines dorsoventral pattern in the Drosophila embryo. Cell 59, 1189–1202 (1989).

    Article  CAS  Google Scholar 

  11. Belvin, M. P., Jin, Y. & Anderson, K. V. Cactus protein degradation mediates Drosophila dorsal-ventral signaling. Genes Dev. 9, 783–793 (1995).

    Article  CAS  Google Scholar 

  12. Bergmann, A. et al. Agradient of cytoplasmic Cactus degradation establishes the nuclear localization gradient of the dorsal morphogen in Drosophila. Mech. Dev. 60, 109–123 (1996).

    Article  CAS  Google Scholar 

  13. Reach, M. et al. Agradient of Cactus protein degradation establishes dorsoventral polarity in the Drosophila embryo. Dev. Biol. 180, 353–364 (1996).

    Article  CAS  Google Scholar 

  14. DiDonato, J. A., Mercurio, F. & Karin, M. Phosphorylation of IκBα precedes but is not sufficient for its dissociation from NF-κB. Mol. Cell Biol. 15, 1302–1311 (1995).

    Article  CAS  Google Scholar 

  15. Lin, Y. C., Brown, K. & Siebenlist, U. Activation of NF-κB requires proteolysis of the inhibitor IκBα: signal-induced phosphorylation of IκBα alone does not release active NF-κB. Proc. Natl Acad. Sci. USA 92, 552–556 (1995).

    Article  ADS  CAS  Google Scholar 

  16. Miyamoto, S., Maki, M., Schmitt, M. J., Hatanaka, M. & Verma, I. M. Tumor necrosis factor α-induced phosphorylation of IκBα is a signal for its degradation but not dissociation from NF-κB. Proc. Natl Acad. Sci. USA 91, 12740–12744 (1994).

    Article  ADS  CAS  Google Scholar 

  17. Hoffmann, J. A. & Reichhart, J.-M. Drosophila immunity. Trends Cell Biol. 7, 309–316 (1997).

    Article  CAS  Google Scholar 

  18. Lemaitre, B. et al. Arecessive mutation, immune deficiency(imd), defines two distinct control pathways in the Drosophila host defense. Proc. Natl Acad. Sci. USA 92, 9465–9469 (1995).

    Article  ADS  CAS  Google Scholar 

  19. Corbo, J. C. & Levine, M. Characterization of an immunodeficiency mutant in Drosophila. Mech. Dev. 55, 211–220 (1996).

    Article  CAS  Google Scholar 

  20. Reichhart, J.-M. et al. Insect immunity: developmental and inducible activity of the Drosophila diptericin promoter. EMBO J. 11, 1469–1477 (1992).

    Article  CAS  Google Scholar 

  21. Williams, M. J., Rodriguez, A., Kimbrell, D. A. & Eldon, E. D. The 18-wheeler mutation reveals complex antibacterial gene regulation in Drosophila host defense. EMBO J. 16, 6120–6130 (1997).

    Article  CAS  Google Scholar 

  22. Hoffmann, J. A., Hetru, C. & Reichhart, J.-M. The humoral antibacterial response of Drosophila. FEBS Lett. 325, 63–66 (1993).

    Article  CAS  Google Scholar 

  23. Kadalayil, L., Petersen, U.-M. & Engström, Y. Adjacent GATA and κB-like motifs regulate the expression of a Drosophila immune gene. Nucleic Acids Res. 25, 1233–1239 (1997).

    Article  CAS  Google Scholar 

  24. Arenzana-Seisdedos, F. et al. Inducible nuclear expression of newly synthesized IκBα negatively regulates DNA-binding and transcriptional activities of NF-κB. Mol. Cell Biol. 15, 2689–2696 (1995).

    Article  CAS  Google Scholar 

  25. Beg, A. A., Sha, W. C., Bronson, R. T. & Baltimore, D. Constitutive NF-κB activation, enhanced granulopoiesis and neonatal lethality in IκBα-deficient mice. Genes Dev 9, 2736–2746 (1995).

    Article  CAS  Google Scholar 

  26. Klement, J. F. et al. IκBα deficiency results in a sustained NF-κB response and severe widespread dermatitis in mice. Mol. Cell Biol. 16, 2341–2349 (1996).

    Article  CAS  Google Scholar 

  27. Stancovski, I. & Baltimore, D. NF-κB activation: the IκB kinase revealed? Cell 91, 299–302 (1997).

    Article  CAS  Google Scholar 

  28. Anderson, K. V. & Nüsslein-Volhard, C. Information for the dorsal-ventral pattern of the Drosophila embryo is stored as maternal mRNA. Nature 311, 223–227 (1984).

    Article  ADS  CAS  Google Scholar 

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Acknowledgements

We thank R. Steward for antibodies to Dorsal and Cactus; Y. Engström for antibody against Dif; B. Lemaitre for the diptericin-lacZ transgenic flies; M. Dushay for the diptericin cDNA; Y. Lu and S. Li for help with mapping; and M. Baylies, M. Belvin and T. Bestor for comments on the manuscript. This work was supported by NIH and NSF grants to K.V.A. and the Memorial Sloan-Kettering Cancer Center Support Grant. L.P.W. is a Leukemia Society of America Special Fellow.

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Wu, L., Anderson, K. Regulated nuclear import of Rel proteins in the Drosophila immune response. Nature 392, 93–97 (1998). https://doi.org/10.1038/32195

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