Journal:FEBS Journal:1

Flexible regions govern promiscuous binding of IL-24 to receptors IL-20R1 and IL-22R1

Jiří Zahradník, Lucie Kolářová, Yoav Peleg, Petr Kolenko, Silvie Svidenská, Tatsiana Charnavets, Tamar Unger, Joel L. Sussman, and Bohdan Schneider ^[1]

Molecular Tour
Interleukin 24 (IL-24) is cytokine, member of Interleukin 10 family. It forms an IL-20 subfamily with IL-19, IL-20, IL-22 because all these interleukins use the common class II cytokine receptor subunits and have similarities in biological functions [1]. IL-24 signals via two heterodimeric receptor complexes IL-22R1/IL-20R2 and IL-20R1/IL-20R2 and activates the STAT3 and STAT1 signaling (fig.1) [2, 3]. IL-24 is associated with multiple diseases, including the promotion and amplification of inflammatory responses during autoimmune and chronic inflammation [1], psoriasis-like skin inflammation [4], epidermal inflammation induced by stresses [5], inflammatory bowel disease [6, 7], and also with host defense during bacterial infection [8]. Some studies suggest anti-cancer activities that increased the interest in this molecule. One of the stable variants (IL-24B) was crystallized, its structure solved at 1.3 Å resolution and deposited to PDB under the code 6gg1. This structure together with the recently published crystal structure of the ternary complex of IL-24 fused to IL-22R1 and co-expressed with IL-20R2 (PDB ID 6df3, [13]) allowed us to analyze the role of the mutated amino acid residues protein stability, flexibility, and binding to the cognate receptors (fig.2). Based on the analysis, we expressed a series of variants back engineered from the PROSS designed variant by changing the critical residues back to their wild types. We revealed that re-introduction of a single IL-24 wild type residue (T198) to the patch interacting with receptors 1 restored 80 % of the binding affinity and signaling capacity accompanied by an acceptable drop in the protein stability by 9°C.

1. Rutz S, Wang X & Ouyang W (2014) The IL-20 subfamily of cytokines--from host defence to tissue homeostasis, Nat Rev Immunol 14, 783-95.

2. Dumoutier L, Leemans C, Lejeune D, Kotenko SV & Renauld JC (2001) Cutting edge: STAT activation by IL-19, IL-20 and mda-7 through IL-20 receptor complexes of two types, J Immunol 167, 3545-9.

3. Wang M & Liang P (2005) Interleukin-24 and its receptors, Immunology 114, 166-70. 4. Kumari S, Bonnet MC, Ulvmar MH, Wolk K, Karagianni N, Witte E, Uthoff-Hachenberg C, Renauld JC, Kollias G, Toftgard R, Sabat R, Pasparakis M & Haase I (2013) Tumor necrosis factor receptor signaling in keratinocytes triggers interleukin-24-dependent psoriasis-like skin inflammation in mice, Immunity 39, 899-911. 5. Jin SH, Choi D, Chun YJ & Noh M (2014) Keratinocyte-derived IL-24 plays a role in the positive feedback regulation of epidermal inflammation in response to environmental and endogenous toxic stressors, Toxicol Appl Pharmacol 280, 199-206. 6. Andoh A, Shioya M, Nishida A, Bamba S, Tsujikawa T, Kim-Mitsuyama S & Fujiyama Y (2009) Expression of IL-24, an activator of the JAK1/STAT3/SOCS3 cascade, is enhanced in inflammatory bowel disease, J Immunol 183, 687-95. 7. Fonseca-Camarillo G, Furuzawa-Carballeda J, Granados J & Yamamoto-Furusho JK (2014) Expression of interleukin (IL)-19 and IL-24 in inflammatory bowel disease patients: a cross-sectional study, Clin Exp Immunol 177, 64-75. 8. Ma Y, Chen H, Wang Q, Luo F, Yan J & Zhang XL (2009) IL-24 protects against Salmonella typhimurium infection by stimulating early neutrophil Th1 cytokine production, which in turn activates CD8+ T cells, Eur J Immunol 39, 3357-68.

9. Goldenzweig A, Goldsmith M, Hill SE, Gertman O, Laurino P, Ashani Y, Dym O, Unger T, Albeck S, Prilusky J, Lieberman RL, Aharoni A, Silman I, Sussman JL, Tawfik DS & Fleishman SJ (2016) Automated Structure- and Sequence-Based Design of Proteins for High Bacterial Expression and Stability, Mol Cell 63, 337-346.

10. Musil M, Stourac J, Bendl J, Brezovsky J, Prokop Z, Zendulka J, Martinek T, Bednar D & Damborsky J (2017) FireProt: web server for automated design of thermostable proteins, Nucleic Acids Res 45, W393-W399.

11. Frey S & Gorlich D (2014) A new set of highly efficient, tag-cleaving proteases for purifying recombinant proteins, J Chrom A 1337, 95-105.

12. Frey S & Gorlich D (2014) Purification of protein complexes of defined subunit stoichiometry using a set of orthogonal, tag-cleaving proteases, J Chrom A 1337, 106-15. 13. Lubkowski J, Sonmez C, Smirnov SV, Anishkin A, Kotenko SV & Wlodawer A (2018) Crystal Structure of the Labile Complex of IL-24 with the Extracellular Domains of IL-22R1 and IL-20R2, J Immunol , ji1800726.

References

1. ↑ REF