State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China.
State Key Laboratory of Crop Stress Biology for Arid Areas/Shaanxi Key Laboratory of Apple, College of Horticulture, Northwest A&F University, Yangling, Shaanxi 712100, China.
Int J Biol Macromol. 2024 Nov;279(Pt 3):135331. doi: 10.1016/j.ijbiomac.2024.135331. Epub 2024 Sep 3.
Low temperatures can seriously affect apple yield and can also cause chilling injury to apple fruit. γ-aminobutyric acid (GABA) plays an important role in improving plant stress resistance. Some studies have reported that GABA can improve cold resistance in plants, only through exogenous treatment; however, the molecular mechanism of its resistance to low temperature is still unknown. This result suggested that exogenous GABA treatment of both apple seedlings and fruit could improve the resistance of apple to low temperatures. MdGAD1, a key gene involved in GABA synthesis, was overexpressed in tomato plants and apple callus to improve their cold tolerance. Both yeast one-hybrid and luciferase assay showed that MdCBF3 could bind to the MdGAD1 promoter to activate its expression and promote GABA synthesis. These results revealed a molecular mechanism utilizing the MdCBF3-MdGAD1 regulatory module that can enhance cold resistance by increasing endogenous GABA synthesis in apple.
低温会严重影响苹果的产量，并可能导致苹果果实冷害。γ-氨基丁酸（GABA）在提高植物抗逆性方面起着重要作用。一些研究报告称，GABA 可以通过外源处理提高植物的抗寒性；然而，其对低温的抗性的分子机制尚不清楚。该结果表明，外源 GABA 处理苹果幼苗和果实均可提高苹果对低温的抗性。MdGAD1 是 GABA 合成的关键基因，在番茄植株和苹果愈伤组织中过表达，以提高其耐寒性。酵母单杂交和荧光素酶检测均表明 MdCBF3 可以与 MdGAD1 启动子结合，激活其表达，促进 GABA 的合成。这些结果揭示了一个分子机制，利用 MdCBF3-MdGAD1 调控模块可以通过增加苹果内源 GABA 的合成来增强其抗寒性。
