Scientific sessions, CRG Group Leader Seminars
Stem Cells and Cancer Group, Cancer Programme, IMIM (Hospital del Mar Medical Research Institute)
IκBα is largely known as the main inhibitor of NF-κB activation. However, we recently found that SUMOylation and phosphorylation of IκBα provide a novel nuclear function for this protein, which is mostly NF-κB independent. We now found that SUMOylated IκBα is also distributed in the cytoplasm of cancer cells leading to the retention and functional abrogation of transcriptional repressors such as SuZ12 or NCoR. Our data indicated that IKK activity regulates SUMO-IκBα distribution and function, mostly by affecting its phosphorylation. Our current studies aim to determine which is the contribution of SUMOylation and phosphorylation to IκBα function and to identify drugs that revert specific tumour-associated function of SUMOylated IκBα.