To better explore the impact of exogenous GABA on tomato fruit quality, we explored the effects of GABA (20 mM) on tomato fruits at different developmental stages. The results showed that spraying GABA 3 days before harvest improved the quality of fruits, primarily in terms of amino acid, organic acid, and soluble sugar content. Transcriptome and metabolome data indicated that exogenous GABA enters cells and mitochondria through GABA transporters, thereby simulating endogenous GABA metabolism and enhancing the activity of genes related to amino acids and organic acids metabolism, and elevating the levels of amino acids and organic acids. Moreover, the application of exogenous GABA promoted the contents of glucose, fructose, and sucrose by affecting the expression of genes related to sugar metabolism. It was found that the mechanism of exogenous GABA in increasing fruit sugar content involved promoting sucrose synthesis, partially inhibiting glycolysis, and increasing the content of trehalose 6-phosphate. This study also provides a new model for the mechanism through which exogenous GABA affects tomato quality.

中文翻译：

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外源 GABA 通过调节氨基酸、有机酸和糖的代谢来改善番茄果实的品质


为了更好地探究外源 GABA 对番茄果实品质的影响，我们探讨了 GABA （20 mM） 对不同发育阶段番茄果实的影响。结果表明，在收获前 3 天喷施 GABA 可以提高水果的品质，主要是在氨基酸、有机酸和可溶性糖含量方面。转录组和代谢组数据表明，外源GABA通过GABA转运蛋白进入细胞和线粒体，从而模拟内源GABA代谢，增强氨基酸和有机酸代谢相关基因的活性，提高氨基酸和有机酸的水平。此外，外源 GABA 的应用通过影响糖代谢相关基因的表达来促进葡萄糖、果糖和蔗糖的含量。研究发现，外源GABA增加果实糖含量的机制包括促进蔗糖合成、部分抑制糖酵解和增加海藻糖6-磷酸含量。本研究为外源 GABA 影响番茄品质的机制提供了新的模型。