May function as a negative regulator of NF-kappa-B by preventing RELA/p65 phosphorylation at 'Ser-536', thereby inhibiting its transcriptional activity. Through NF-kappa-B regulation may control cytokine release upon Toll-like receptors activation and therefore play a role in modulation of innate immunity. May also play a role in cell cycle progression and apoptotic process. Targeted to the nucleus upon TNF-alpha treatment. Expressed in all tissues tested, including spleen, lymph node, thymus, tonsil, peripheral blood leukocyte, bone marrow, liver, heart, brain, placenta, lung, skeletal muscle, kidney and pancreas. Expressed in fetal liver. Up-regulated by inflammatory stimulus (LPS). Likely derived from retrogene insertion of an NLRP2/NLRP7-like gene, it was originally considered a pseudogene. However, it turns out to be functional and under purifying selection.