Role of extracellular signal regulated kinase 5 in neuronal survival.

The newest member of the mitogen activated protein (MAP) kinase family of proteins, extracellular signal regulated kinase 5 (ERK5; also known as big-mitogen activated kinase 1 or BMK1) is widely expressed in many tissues including the brain. Although growth factor activation of ERK5 in non-neuronal cells has been shown to contribute to cell proliferation, differentiation and transformation, until recently no information was available on the role of ERK5 in neuronal survival. Recent data suggests that ERK5 is activated by neurotrophic factors in primary neuronal cells and plays an important role in neurotrophin mediated neuronal survival. These data also suggest that the mechanism of ERK5-mediated survival involves transcriptional regulation.