Inhibitor Of Nuclear Factor Kappa B Kinase Interacting Protein (IKBIP)

IKIP orthologs are found in other species, including mouse, rat, pig, cow, and Xenopus laevis. Mouse and rat Ikip1 and Ikip2 encode 373- and 345-amino acid proteins, respectively, and the human IKIP1 protein shows 77% and 79% identity with mouse and rat Ikip1, respectively. Northern blot analysis detected expression of 3 IKIP1 transcripts of 1.3, 1.6 and 2.9 kb in lung, kidney, spleen, thymus, and skeletal muscle. Immunofluorescence analysis showed that both transfected and endogenous IKIP1 localizes to the endoplasmic reticulum, and deletion of the hydrophobic region results in uniform distribution of IKIP1 throughout the cell. Tunicamycin and endoglycosidase H treatment demonstrated that IKIP1 and IKIP2 are glycosylated, and targeted mutation of IKIP1 showed that glycosylation occurs at asparagine-154.