Regulation of stress responses by intracellular vesicle trafficking?

Being grounded to one place, plants are constantly exposed to unexpected changes in the surrounding environment. Often, the changes in environmental conditions can be very rapid, compelling the plants to continuously monitor the outside environment and to adjust their metabolism to new conditions. Many of the primary environmental stresses ensue the development of a secondary oxidative stress, resulting in tissue damage and necrosis. The acclimation process almost invariably involves changes in the pattern of expressed proteins and other molecules. This necessitates the removal of the existing molecules from their compartments and the delivery of new compounds to their target organelles. The trafficking of macromolecules is performed by a bi-directional intracellular vesicle trafficking system that delivers newly synthesized molecules to organelles and retrieves material from the organelles to cytosolic compartments, such as vacuoles or lysosomes. The plasma membrane is among the organelles that are most exposed to oxidative stress damage and therefore must be constantly recycled. Here I propose that, by adjusting the rate of trafficking to and from the plasma membrane, the cells can regulate the stress outcome. Since the vesicle trafficking is closely linked to general signal transduction pathways, such as the phosphoinositide kinase pathway, and is influenced by major plant hormones, such as abscisic acid and auxin, the vesicle trafficking machinery holds the potential to regulate the plant responses to different environmental stresses.