Mechanistic understanding of GABA and trehalose in modulating plant response to drought stress

Abstract

Drought stress is one of the most critical environmental factors that hinders plant growth, productivity, and survival worldwide. This review presents the detrimental effects of drought stress on plant growth, its development, and key physical, physiological, and biochemical traits. It is also reviewing effective strategies related to drought management to alleviate these impacts. In fact, plants employ various physiological and biochemical mechanisms to counteract drought stress, with γ-aminobutyric acid (GABA) and trehalose emerging as significant masters of drought tolerance. GABA is an amino acid that isn't found in proteins. It is an important osmoprotectant, antioxidant, and signaling molecule that changes how stress-responsive pathways work. It enhances photosynthetic efficiency, regulates reactive oxygen species (ROS), and stabilizes cellular structures. Similarly, trehalose, a non-reducing disaccharide, acts as a crucial osmolyte, protecting plants from dehydration by stabilizing proteins and membranes, decreasing oxidative damage, and enhancing metabolic efficiency. Both molecules play essential roles in stress-related gene regulation, scavenging of ROS, and maintaining homeostasis of cellular environment under drought conditions. Lastly, reviews also highlight the current knowledge on the biosynthesis and metabolism of GABA and trehalose, emphasizing their potential applications in improving drought resilience in crops through genetic modification and exogenous application. Furthermore, it underscores their value of these two components in helping plants withstand harsh environmental challenges and lessen the adverse effects of abiotic stress, i.e., drought stress. Understanding these mechanisms provides valuable insights for enhancing plant performance in water-limited environments.