No abstract

Extracellular-signal-regulated kinase 5 (ERK5), also termed big MAPK1 (BMK1), is the most recently discovered member of the mitogen-activated protein kinase (MAPK) family. It is expressed in a variety of tissues and is activated by a range of growth factors, cytokines and cellular stresses. Targeted deletion of Erk5 in mice has revealed that the ERK5 signalling cascade is critical for normal cardiovascular development and vascular integrity. In vitro studies have revealed that, in endothelial cells, ERK5 is required for preventing apoptosis, mediating shear-stress signalling and regulating tumour angiogenesis. The present review focuses on our current understanding of the role of ERK5 in regulating endothelial cell function.

Extracellular signal-regulated kinase 5 (ERK5), also known as big MAPK (BMK1), is the most recently identified member of the mitogen-activated kinase pathway. It is ubiquitously expressed in mammalian cells and is activated by a number of growth factors. Gene knockout studies in mice have shown a critical role for ERK5 cardiovascular development and vascular integrity. Current methods to detect ERK5 activation in cells have relied on in vitro kinase assays and more recently phospho-specific antibodies. However, antibodies produced against phosphorylated proteins can often yield inconsistent data. Phos-tag™ Acrylamide is a reagent that enables specific tagging of phosphorylated proteins, resulting in retarded mobility and a distinct upward band shift from the non-phosphorylated protein following SDS-PAGE. Here, we describe the details of Phosphate affinity SDS-PAGE of ERK5 using acrylamide-pendant Phos-tag™.