Medicina (Buenos Aires)
versión On-line ISSN 1669-9106
NOJEK, Ignacio M. et al. Different enzymatic activities recruitment by specific domains of TIF2 are involved in NF-kB transactivation. Medicina (B. Aires) [online]. 2004, vol.64, n.2, pp. 135-138. ISSN 1669-9106.
We have previously shown that nuclear receptor coactivator overexpression significantly enhanced NF-kB activity in a dose response manner. We studied the mechanism by which TIF2 regulates NF-kB activity. We determined that: 1) the p38 specific inhibitor reduces 50% NF-kB transcriptional activity, even in cells that overexpress distinct TIF2 deletions; 2) there is a physical interaction between TIF2 and p38 and RelA determined through in vitro translated protein bindind assays; 3) TIF2 is a p38 substrate; 4) there is a physical interaction between TIF2 and IKK in TNF-a 20 ng/ml stimulated or not HEK 293 cell protein extract, and IkB only in basal conditions, determined by binding pull down assays. This NF-kB complex regulates its activity and targets gene expression in a determined physiologic context depending on the coactivator complex content.
Palabras clave : Nuclear receptor coactivators; NF-kB; MAPK; TIF2.