Plant cortical microtubules are putative sensors under abiotic stresses

In this article, we review current knowledge on the dynamic changes and roles of microtubule (MT) arrays under abiotic stresses. The results emphasize the existence of highly dynamic changes, complex regulatory networks, and the vitally important role of MTs in the response to abiotic stresses. In particular, some findings indicate that cortical microtubules (CMTs) underlying the plasma membrane play an important role in abiotic stress-induced signaling pathways. Therefore, we also discuss the relationship between CMTs and abiotic stress signaling. The data show that at least three early response mechanisms, namely, Ca2+ signaling, abscisic acid biosynthesis, and the formation of plant cell walls, follow CMT reorganization and are mediated by dynamic changes in the CMTs. Consequently, we propose that the CMTs are not only part of the plant response to abiotic stresses but might also serve as a type of cell wall membrane-bound sensor that perceives the stress stimuli to generate adaptive signals and responses of cells.