Overexpression of Salicylic Acid Carboxyl Methyltransferase (CsSAMT1) Enhances Tolerance to Huanglongbing Disease in Wanjincheng Orange (Citrus sinensis (L.) Osbeck)

文献类型： 外文期刊

第一作者： Zou, Xiuping

作者： Zou, Xiuping;Zhao, Ke;Liu, Yunuo;Du, Meixia;Zheng, Lin;Wang, Shuai;Xu, Lanzhen;Peng, Aihong;He, Yongrui;Long, Qin;Chen, Shanchun

作者机构：

关键词： citrus; disease tolerance; HLB; SA; MeSA; CsSAMT1

期刊名称：INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES （ 影响因子：4.556； 五年影响因子：4.653 ）

ISSN：

年卷期： 2021 年 22 卷 6 期

页码：

收录情况： SCI

摘要： Citrus Huanglongbing (HLB) disease or citrus greening is caused by Candidatus Liberibacter asiaticus (Las) and is the most devastating disease in the global citrus industry. Salicylic acid (SA) plays a central role in regulating plant defenses against pathogenic attack. SA methyltransferase (SAMT) modulates SA homeostasis by converting SA to methyl salicylate (MeSA). Here, we report on the functions of the citrus SAMT (CsSAMT1) gene from HLB-susceptible Wanjincheng orange (Citrus sinensis (L.) Osbeck) in plant defenses against Las infection. The CsSAMT1 cDNA was expressed in yeast. Using in vitro enzyme assays, yeast expressing CsSAMT1 was confirmed to specifically catalyze the formation of MeSA using SA as a substrate. Transgenic Wanjincheng orange plants overexpressing CsSAMT1 had significantly increased levels of SA and MeSA compared to wild-type controls. HLB resistance was evaluated for two years and showed that transgenic plants displayed significantly alleviated symptoms including a lack of chlorosis, low bacterial counts, reduced hyperplasia of the phloem cells, and lower levels of starch and callose compared to wild-type plants. These data confirmed that CsSAMT1 overexpression confers an enhanced tolerance to Las in citrus fruits. RNA-seq analysis revealed that CsSAMT1 overexpression significantly upregulated the citrus defense response by enhancing the transcription of disease resistance genes. This study provides insight for improving host resistance to HLB by manipulation of SA signaling in citrus fruits.

分类号：

  • 相关文献
作者其他论文 更多>>

微信小程序