R2R3-MYB Transcription Factor MdMYB73 Confers Increased Resistance to the Fungal Pathogen Botryosphaeria dothidea in Apples via the Salicylic Acid Pathway
R2R3-MYB Transcription Factor MdMYB73 Confers Increased Resistance to the Fungal Pathogen Botryosphaeria dothidea in Apples via the Salicylic Acid Pathway
复制标题
R2R3-MYB 转录因子 MdMYB73 通过水杨酸途径增强苹果对真菌病原体 Botryosphaeria dothidea 的抵抗力
DOI：
10.1021/acs.jafc.0c06740
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发表时间：
2021-01-13
影响因子：
6.1
通讯作者：
Hao, Yu-Jin
中科院分区：
文献类型：
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作者：
Gu, Kai-Di;Zhang, Quan-Yan;Hao, Yu-Jin
MYB转录因子参与多种生物学过程。然而，MYB转运蛋白影响植物对苹果轮纹病抗性的分子机制尚不清楚。在此，从“皇家嘎拉”苹果中克隆了R2R3-MYB基因MdMYB73，并对其功能进行了鉴定。QRT-PCR和GUS染色表明，MdMYB73在苹果果实和转基因愈伤组织中均有较强的诱导。MdMYB73过表达提高了苹果愈伤组织和果实对白粉病的抗性，而MdMYB73抑制作用减弱。在表达MdMYB73的拟南芥中，也观察到对B.dothidea的抗性增加。有趣的是，在MdMYB73高表达的植物材料中，水杨酸(SA)含量以及SA合成和信号相关基因的表达水平高于野生型对照，这表明MdMYB73可能通过SA途径提高了对多年生黑穗病的抗性。最后，我们发现MdMYB73与B.dothei的正向调节因子MdWRKY31相互作用。MdWRKY31和MdMYB73共同提高了苹果对白僵菌的抗性。我们的结果阐明了MdMYB73提高对白僵菌抗性的机制，并表明这种抗性可能是通过调节SA途径来影响的。
MYB transcription factors (TFs) participate in many biological processes. However, the molecular mechanisms by which MYB TFs affect plant resistance to apple ring rot remain poorly understood. Here, the R2R3-MYB gene MdMYB73 was cloned from "Royal Gala" apples and functionally characterized as a positive regulator of the defense response to Botryosphaeria dothidea. qRT-PCR and GUS staining demonstrated that MdMYB73 was strongly induced in apple fruits and transgenic calli after inoculation with B. dothidea. MdMYB73 overexpression improved resistance to B. dothidea in apple calli and fruits, while MdMYB73 suppression weakened. Increased resistance to B. dothidea was also observed in MdMYB73-expressing Arabidopsis thaliana. Interestingly, salicylic acid (SA) contents and the expression levels of genes related with SA synthesis and signaling were greater in MdMYB73-overexpressing plant materials compared to wild-type controls after inoculation, suggesting that MdMYB73 might enhance resistance to B. dothidea via the SA pathway. Finally, we discovered that MdMYB73 interacts with MdWRKY31, a positive regulator of B. dothidea. Together, MdWRKY31 and MdMYB73 enhanced B. dothidea resistance in apples. Our results clarify the mechanisms by which MdMYB73 improves resistance to B. dothidea and suggest that resistance may be affected by regulating the SA pathway.