Beyond the Usual Suspects: Physiological Roles of the Arabidopsis Amidase Signature (AS) Superfamily Members in Plant Growth Processes and Stress Responses

The evolutionary success of land plants largely relies on their ability to cope with constant environmental fluctuations, which negatively impact their reproductive fitness and trigger adaptational responses to biotic and abiotic stresses. In this challenging scenario, comprehensive research efforts so far aimed at depicting the roles of well-known phytohormones, mainly auxins, along with brassinosteroids, jasmonates, and abscisic acid, although the signaling networks coordinating the crosstalk among them remains vaguely understood. Accordingly, this review focuses on the Arabidopsis Amidase Signature (AS) superfamily members, highlighting the hitherto relatively underappreciated functions of AMIDASE1 (AMI1) and FATTY ACID AMIDE HYDROLASE (FAAH), as crucial coordinators of the growth-defense response trade-off by modulating auxin and ABA homeostasis.