MAIL, a novel nuclear IκB protein that potentiates LPS-induced IL-6 production

We have identified and characterized a novel member of the ankyrin-repeat family named 'molecule possessing ankyrin-repeats induced by lipopolysaccharide' (MAIL). The C-terminal portion of MAIL shared high sequence homology,vith the I kappaB family. Intraperitoneal injection of lipopolysaccharide (LPS) into mice rapidly (< 0.5 h) induced MAIL mRNA in various tissues, particularly in the spleen, lymph node, and lung. Ectopically expressed MAIL was localized in the nucleus, and remarkably potentiated the LPS-induced mRNA expression and secretion of interleukin (IL)-6 in Swiss 3T3 cells, These findings indicate that MAIL is one of the nuclear IB proteins and an activator of IL-6 production. (C) 2000 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.