THE INTERFERON-ACTIVATABLE GENE-200-CLUSTER - FROM STRUCTURE TOWARD FUNCTION

The antimicrobial, cell growth-regulatory and immunomodulatory activities of the interferons (IFNs) are mediated by IFN-inducible proteins. One family of these (200 family) including the p202, p203, p204 and D3 proteins is encoded by a cluster of six or more structurally-related murine genes in the q21-q23 region of chromosome 1 (gene 200 cluster). Two homologous human genes (MNDA and IFI 16) were also identified. The 200 family proteins share one or two partially conserved 200 amino acid segments. At least four of the proteins are nuclear One of these , p202, binds the hypophosphorylated form of the growth regulatory pRb protein and also the E2F-1 transcription factor that is involved in cell cycling. In transfected cells p202 inhibits E2F activity and slows down cell proliferation. Information about the genes and proteins of the 200 cluster is surveyed.