文摘
Oncostatin M (OM) is a member of the cytokine family which regulates the proliferation anddifferentiation of a variety of cell types and includes interleukin-6 (IL-6), leukemia inhibitory factor (LIF),and granulocyte-colony stimulating factor (G-CSF). This family of proteins adopts a four-helix bundlefold with up-up-down-down topology and contains intramolecular disulfide bonds. Since an X-ray orNMR structure for OM is not currently available, a homology model for OM was determined from theX-ray structures of human growth hormone (hGH), LIF, and G-CSF where the alignment was based onsecondary structure instead of sequence. The OM secondary structure was determined from NMR structuraldata, and the secondary structures for hGH, LIF, and G-CSF were obtained from the reported X-raystructures. The resulting homology model was refined using sequential NOE distance 13C restraints,chemical shift information, and a conformational database.