Elucidation of the Arabidopsis NPK1-related protein kinases (ANPs) role in cell wall biosynthesis and signalling

The plant cell wall (CW) is a resilient barrier against environmental stresses. It is built to resist pathogenic attacks and is the place where many danger-related signals exert their action. Local mechanical damage of the CW leads to systemic protection response with an important role played by jasmonic acid (JA) and ROS. The MAP triple kinases (MAP3K) named Arabidopsis NPK1-RELATED PROTEIN KINASES (ANP1-3) are involved in this process. Loss of ANPs leads to a CW with a lower content of cellulose, and a compromised response to CW-derived damage-associated molecular patterns (DAMPs), with alteration of ROS and JA accumulation. A strong parallelism has been observed between the response to the cellulose biosynthesis inhibitor isoxaben (ISX), and the phenotype associated with the lack of ANPs. The aim of this study is providing knowledge of the molecular mechanisms underlying the action of ANPs (and ISX) on the cell wall, investigating also the associated subcellular dynamics. Moreover, since JA and ROS have a pivotal role in the response to the depletion of cell wall cellulose, we are investigating the role of these signals in the alterations observed in the anp mutants.