Imgenex Corp. develops and commercializes novel reagents for the scientific study of human biology and disease and for the production of new diagnostic assays and potential therapies of such diseases. These novel reagents include antibodies, gene and protein expression systems, and arrays of various cells and tissues for use in studies of functional genomics. Areas of biological interest at IMGENEX include cancer, apoptosis (programmed cell death), molecular signaling pathways, cellular aging, and metabolic and infectious diseases.
NF-kB (nuclear factor kB) is sequestered in the cytoplasm by IkB family of inhibitory proteins that mask the nuclear localization signal of NF-kB thereby preventing translocation of NF-kB to the nucleus (1). External stimuli such as tumor necrosis factor or other cytokines results in phosphorylation and degradation of IkB releasing NF-kB dimers. NF-kB dimer subsequently translocates to the nucleus and activates target genes. Synthesis of IkBa is autoregulated (2). IkB proteins are phosphorylated by IkB kinase complex consisting of at least three proteins, IKK1/a, IKK2/b, and IKK3/g (3-5). Recently, using a substractive hybridization technique, a novel kinase, IKKi/IKKe has been isolated (6). LPS increases IKKi mRNA level in mouse macrophage cell lines. This protein has significant sequence homology with kinase domains of IKK1/a and IKK-2/b. Overexpression of wild type IKK-i in cells phosphorylates Ser32 and Ser36 of IkBa.
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