GABA in Relation to Cold and Chilling Stress

Abstract

Many countries around the world are currently grappling with the consequences of climate changes, which have a profound impact on crop productivity and have a detrimental impact on plant growth. This, in turn, has led to a decline in the yield and quality of agricultural crops in numerous regions. Among the various environmental factors, low-temperature damage stands out as one of the most significant challenges faced by many regions. Plants have developed various mechanisms, including γ-aminobutyric acid (GABA), to adapt to and resist the effects of cold stress. GABA is synthesized through several pathways, including glutamate decarboxylation, polyamine (PA) degradation, and proline nonenzymatic conversion. GABA serves as a defensive molecule in low-temperature tolerance. The response strategies of GABA in coping with cold stress are thoroughly investigated, particularly concerning its role in mitigating the generation of reactive oxygen species (ROS) and enhancing antioxidant systems within plants. In addition, GABA is found to bolster the nonenzymatic antioxidant system, regulate phenol and ascorbic acid metabolism, and promote PA synthesis. It also plays a crucial role in protecting chloroplast integrity and maintaining higher ATP content and energy charge. This text also delves into future perspectives, challenges, and conclusions regarding the role of GABA in enhancing cold stress tolerance.