The role of MAP-Kinases in anxiety and depression - studies with knockout and knockdown mouse models.

In the last years, RNA interference (RNAi)-mediated gene knockdown has developed into a routine method to assess gene function in cultured mammalian cells in a fast and easy manner. Here, this method has been modified to achieve conditional gene knockdown in the mouse via the Cre/loxP system. Mice expressing such RNAi constructs against components of the MAPK (mitogen-activated protein kinases) pathway in the adult brain, together with corresponding classical knockout mice, have been analyzed for behavioral changes. These functional studies revealed an essential role for Braf, Mek1, and Mek2 in anxiety and emotional behavior and in the development of disorders in this regard