Crystals of soluble interleukin-1 receptor complexed with its natural antagonist reveal a 1:1 receptor-ligand complex

• Published in: FEBS letters 1995-10, Vol.373 (1), p.39-40
• Main Authors: Schreuder, Herman, Tardif, Chantal, Soffientini, Adolfo, Sarubbi, Edoardo, Akeson, Ann, Bowlin, Terry, Yanofsky, Stephen, Barrett, Ronald W.
• Format: Article
• Language: English
• Subjects: Base Sequence; Cloning, Molecular; Crystallization; Crystallography, X-Ray; Cytokine; DNA Primers; Human; Humans; IL-1, interleukin-1; IL-1ra, interleukin-1 receptor antagonist; Interleukin 1 Receptor Antagonist Protein; Interleukin-1 receptor; Interleukin-1 receptor antagonist; Ligands; Molecular Sequence Data; Polymerase Chain Reaction; Protein crystal; Receptors, Interleukin-1 - chemistry; Receptors, Interleukin-1 - isolation & purification; Receptors, Interleukin-1 - metabolism; Recombinant Proteins - chemistry; Recombinant Proteins - isolation & purification; Recombinant Proteins - metabolism; Sialoglycoproteins - chemistry; Sialoglycoproteins - isolation & purification; Sialoglycoproteins - metabolism; Tumor Cells, Cultured; X-Ray analysis
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(95)01009-4

Interleukin-1 is a cytokine involved in the acute phase response against infection and injury. We obtained crystals of a complex of soluble, recombinant human interleukin-1 receptor and recombinant human interleukin-1 receptor antagonist, a naturally occurring antagonist. The crystals are suitable for X-ray analysis and diffract to 2.7 Å resolution. Solvent content calculations indicate that the crystals contain one receptor and one antagonist molecule per asymmetric unit. Other receptor to antagonist ratios are highly unlikely. These results suggest that the interleukin-1 antagonist binds a single receptor molecule and does not cause receptor aggregation.