Zhengzhou Research Base, State Key Laboratory of Cotton Biology, School of Agricultural Sciences, Zhengzhou University, Zhengzhou, Henan 450001, China.
State Key Laboratory of Cotton Biology, Institute of Cotton Research of Chinese Academy of Agricultural Sciences, Anyang, Henan 455000, China.
Plant Sci. 2023 Mar;328:111582. doi: 10.1016/j.plantsci.2022.111582. Epub 2023 Jan 8.
The soil-borne fungus Verticillium dahliae causes Verticillium wilt (VW), one of the most devastating diseases of cotton. In a previous study showed that GhOPR9 played a positive role in resistance of cotton to VW through the regulation of the Jasmonic acid (JA) pathway. Furtherly, we also found that GhOPR9 interacted with a sucrose galactosyltransferase GhRFS6. Raffinose synthase (RFS) plays a key role in plant innate immunity, including the abiotic stress of drought, darkness. However, there were few reports on the effects of RFS on biotic stress. In this study, we verified the function of GhRFS6 to VW. The expression analysis showed that the GhRFS6 may be regulated by various stresses, and it was upregulated under Vd076 and Vd991 pressures. Inhibition of GhRFS6 expression, hydrogen peroxide (HO) content, lignin content, cell wall thickness and a series of defense responses were decreased, and the resistance of cotton to V. dahliae was decreased. In addition, this study showed that GhRFS6 has glycosyltransferase activity and can participate in the regulation of α-galactosidase activity and raffinose and inositol synthesis. And that galactose was accumulated in cotton roots after GhRFS6 silencing, which is beneficial for the colonization and growth of V. dahliae. Furthermore, overexpression of GhRFS6 in Arabidopsis thaliana enhanced plant resistance to V. dahliae. In GUS staining, the promoter expression position of GhRFS6 was also altered after V. dahliae infection. Meanwhile, GhRFS6 has also been shown to resist VW through the regulation of the JA pathway. These results suggest that GhRFS6 is a potential molecular target for improving cotton resistance to VW.
土传真菌黄萎轮枝菌引起黄萎病（VW），是棉花最具破坏性的疾病之一。在之前的研究中表明，GhOPR9 通过调节茉莉酸（JA）途径在棉花对 VW 的抗性中发挥积极作用。此外，我们还发现 GhOPR9 与蔗糖半乳糖基转移酶 GhRFS6 相互作用。棉子糖合酶（RFS）在植物先天免疫中发挥关键作用，包括干旱、黑暗等非生物胁迫。然而，关于 RFS 对生物胁迫的影响的报道很少。在这项研究中，我们验证了 GhRFS6 对 VW 的功能。表达分析表明，GhRFS6 可能受到各种胁迫的调节，并且在 Vd076 和 Vd991 压力下上调。抑制 GhRFS6 表达、过氧化氢（HO）含量、木质素含量、细胞壁厚度和一系列防御反应降低，棉花对 V. dahliae 的抗性降低。此外，本研究表明 GhRFS6 具有糖基转移酶活性，可参与α-半乳糖苷酶活性和棉子糖和肌醇合成的调节。并且 GhRFS6 沉默后棉根中积累了半乳糖，有利于 V. dahliae 的定殖和生长。此外，在拟南芥中过表达 GhRFS6 增强了植物对 V. dahliae 的抗性。在 GUS 染色中，GhRFS6 的启动子表达位置在 V. dahliae 感染后也发生了改变。同时，GhRFS6 还通过调节 JA 途径来抵抗 VW。这些结果表明 GhRFS6 是提高棉花对 VW 抗性的潜在分子靶标。
