Convergence and specificity in the Arabidopsis MAPK nexus

Although mitogen-activated protein kinase (MAPK) signal transduction cascades are known regulators of various aspects of plant biology, our knowledge of these systems has been largely restricted to a small subset of the MAPKs. However, global analyses are now revealing that many more of these kinases are probably engaged in modulating developmental and fitness adaptation processes in the plant kingdom. In this review, we show how these new findings are beginning to define the overall architecture of plant MAPK signaling, with a particular focus on the interplay between the terminal MPKs and their activators, inactivators and cellular targets.