Download MendeleyStructure of the IL-27 quaternary receptor signaling complex.
Caveney, N.A., Glassman, C.R., Jude, K.M., Tsutsumi, N., Garcia, K.C.(2022) Elife 11
- PubMed: 35579417
- DOI: https://doi.org/10.7554/eLife.78463
- Primary Citation of Related Structures:
7U7N - PubMed Abstract:
Interleukin 27 (IL-27) is a heterodimeric cytokine that functions to constrain T cell-mediated inflammation and plays an important role in immune homeostasis. Binding of IL-27 to cell surface receptors, IL-27Rα and gp130, results in activation of receptor-associated Janus Kinases and nuclear translocation of Signal Transducer and Activator of Transcription 1 (STAT1) and STAT3 transcription factors. Despite the emerging therapeutic importance of this cytokine axis in cancer and autoimmunity, a molecular blueprint of the IL-27 receptor signaling complex, and its relation to other gp130/IL-12 family cytokines, is currently unclear. We used cryogenic-electron microscopy to determine the quaternary structure of IL-27, composed of p28 and Epstein-Barr Virus-Induced 3 (Ebi3) subunits, bound to receptors, IL-27Rα and gp130. The resulting 3.47 Å resolution structure revealed a three-site assembly mechanism nucleated by the central p28 subunit of the cytokine. The overall topology and molecular details of this binding are reminiscent of IL-6 but distinct from related heterodimeric cytokines IL-12 and IL-23. These results indicate distinct receptor assembly mechanisms used by heterodimeric cytokines with important consequences for targeted agonism and antagonism of IL-27 signaling.
Organizational Affiliation:
Department of Molecular and Cellular Physiology, Stanford University School of Medicine, Stanford, United States.
