作者：Tang, Xiaomei; Wang, Xia; Huang, Yue; Ma, Ling; Jiang, Xiaolin; Rao, Muhammad Junaid; Xu, Yuantao; Yin, Ping; Yuan, Meng; Deng, Xiuxin; Xu, Qiang
摘要：Author summary It has been well documented that most citrus cultivars are susceptible to canker disease, while little is known about the resistance or susceptibility of primitive or wild citrus to canker disease. This study reveals that primitive citrus (Atalantia buxifolia) is highly resistant to citrus canker. Transcriptome data demonstrated that Atalantia had an active resistance response to the infection of Xcc, compared with susceptible sweet orange. Our results indicated that natural variations of AbTFIIA gamma gene and AbLOB1 promoter contributed to the resistance. Hence, we propose that the natural mutations of AbTFIIA gamma gene and AbLOB1 promoter could provide candidate targets for breeding canker resistant citrus. Citrus canker caused by Xanthomonas citri subsp. citri (Xcc) is one of the most devastating diseases in citrus industry worldwide. Most citrus cultivars such as sweet orange are susceptible to canker disease. Here, we utilized wild citrus to identify canker-resistant germplasms, and found that Atalantia buxifolia, a primitive (distant-wild) citrus, exhibited remarkable resistance to canker disease. Although the susceptibility gene LATERAL ORGAN BOUNDARIES 1 (LOB1) could also be induced in Atalantia after canker infection, the induction extent was far lower than that in sweet orange. In addition, three of amino acids encoded by transcription factor TFIIA gamma in Atalantia (AbTFIIA gamma) exhibited difference from those in sweet orange (CsTFIIA gamma) which could stabilize the interaction between effector PthA4 and effector binding element (EBE) of LOB1 promoter. The mutation of AbTFIIA gamma did not change its interaction with transcription factor binding motifs (TFBs). However, the AbTFIIA gamma could hardly support the LOB1 expression induced by the PthA4. In addition, the activity of AbLOB1 promoter was significantly lower than that of CsLOB1 under the induction by PthA4. Our results demonstrate that natural variations of AbTFIIA gamma and effector binding element (EBE) in the AbLOB1 promoter are crucial for the canker disease resistance of Atalantia. The natural mutations of AbTFIIA gamma gene and AbLOB1 promoter in Atalantia provide candidate targets for improving the resistance to citrus canker disease.
文献注录：Tang, Xiaomei; Wang, Xia; Huang, Yue; Ma, Ling; Jiang, Xiaolin; Rao, Muhammad Junaid; Xu, Yuantao; Yin, Ping; Yuan, Meng; Deng, Xiuxin; Xu, Qiang. Natural variations of TFIIA gamma gene and LOB1 promoter contribute to citrus canker disease resistance in Atalantia buxifolia [J]. . 2021.
报/刊名：《》，发表于2021
文献类型： [J]
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