Phospho-specific mitogen-activated protein kinase antibodies for ERK, JNK, and p38 activation

Abstract

The phosphorylation of cellular proteins or enzymes may result in alteration of their conformation and/or their enzyme activity. This is best illustrated by a group of enzymes collectively known as mitogen-activated protein (MAP) kinases, whose dual phosphorylation by upstream protein kinases results in their activation. These kinase cascades are found in all eukaryotic organisms and consist of a three-kinase module. The three modules contain the extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 MAPK (p38) pathways. This chapter describes the phospho-specific mitogen-activated protein kinase antibodies for extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 activation. The availability of antibodies that recognize the active form of the various members of MAPKs (ERKs, JNKs, and p38) has made it possible to study the activation of these enzymes in response to a variety of stimuli in an accurate and time-dependent fashion. Similar to the anti-phosphotyrosine antibodies, the dual phospho-specific antibodies have proved to be valuable reagents in the pursuit of selective inhibitors of these enzymes. Studies of these enzymes with these novel antibodies also resulted in the discovery of novel MAPK kinase kinase (MEK) inhibitors such as U0126.