CRYSTAL-STRUCTURE OF A COMPLEX BETWEEN INTERFERON-GAMMA AND ITS SOLUBLE HIGH-AFFINITY RECEPTOR

The crystal structure of interferon-gamma bound to the extracellular f ragment of its high-affinity cell-surface receptor reveals the first v iew of a class-2 cytokine receptor-ligand complex. In the complex, one interferon-gamma homodimer binds two receptor molecules. Unlike the c lass-1 growth hormone receptor complex, the two interferon-gamma recep tors do not interact with one another and are separated by 27 Angstrom . Upon receptor binding, the flexible As loop of interferon-gamma unde rgoes a conformational change that includes the formation of a 3(10) h elix.