ABSTRACT

Gamma-aminobutyric acid (GABA) is a ubiquitous four-carbon, non-protein amino acid. GABA has been widely studied in animal central nervous systems, where it acts as an inhibitory neurotransmitter. In plants, it is metabolized through the GABA shunt pathway, a bypass of the tricarboxylic acid (TCA) cycle. Additionally, it can be synthesized through the polyamine metabolic pathway. GABA acts as a signal in Agrobacterium tumefaciens-mediated plant gene transformation and in plant development, especially in pollen tube elongation (to enter the ovule), root growth, fruit ripening, and seed germination. It is accumulated during plant responses to environmental stresses and pathogen and insect attacks. A high concentration of GABA elevates plant stress tolerance by improving photosynthesis, inhibiting reactive oxygen species (ROS) generation, activating antioxidant enzymes, and regulating stomatal opening in drought stress. The transporters of GABA in plants are reviewed in this work. We summarize the recent research on GABA function and transporters with the goal of providing a review of GABA in plants.

摘要

γ-氨基丁酸（GABA）是普遍存在的四碳非蛋白质氨基酸。GABA已在动物中枢神经系统中得到广泛研究，在该系统中，GABA起到抑制神经递质的作用。在植物中，它是通过GABA分流途径（绕过三羧酸（TCA）循环）代谢的。另外，它可以通过多胺代谢途径合成。GABA在根癌土壤杆菌中起信号作用介导的植物基因转化和植物发育，特别是花粉管伸长（进入胚珠），根系生长，果实成熟和种子萌发。它是在植物对环境压力以及病原体和昆虫侵袭的反应过程中积累的。高浓度的GABA可通过改善光合作用，抑制活性氧（ROS）生成，激活抗氧化酶和调节干旱胁迫下的气孔开放来提高植物的耐逆性。这项工作审查了植物中GABA的转运蛋白。我们总结了最近对GABA功能和转运蛋白的研究，目的是对植物中的GABA进行综述。