文献类型： 外文期刊

作者： Zhao, Yuqiang ¹ ; Yang, Kun ³ ; Wang, Yanxin ² ; Li, Xu ² ; Xia, Chengyao ² ; Huang, Yan ² ; Li, Zhoukun ² ; Zhu, Cancan ¹ ; Cui, Zhongli ² ; Ye, Xianfeng ² ;

作者机构： 1.Jiangsu Prov & Chinese Acad Sci, Inst Bot, Nanjing, Peoples R China

2.Nanjing Agr Univ, Coll Life Sci, Minist Agr & Rural Affairs, Key Lab Agr Environm Microbiol, Nanjing 210095, Peoples R China

3.Guangdong Acad Agr Sci, Crop Res Inst, Guangzhou, Peoples R China

4.Liaocheng Univ, Coll Life Sci, Liaocheng, Peoples R China

关键词： glycoside hydrolases; induced systemic resistance; myxobacteria; plant immune response; xylanase

期刊名称：MOLECULAR PLANT PATHOLOGY （ 影响因子：4.8； 五年影响因子：6.0 ）

ISSN： 1464-6722

年卷期： 2024 年 25 卷 6 期

页码：

收录情况： SCI

摘要： Xylanases derived from fungi, including phytopathogenic and nonpathogenic fungi, are commonly known to trigger plant immune responses. However, there is limited research on the ability of bacterial-derived xylanases to trigger plant immunity. Here, a novel xylanase named CcXyn was identified from the myxobacterium Cystobacter sp. 0969, which displays broad-spectrum activity against both phytopathogenic fungi and bacteria. CcXyn belongs to the glycoside hydrolases (GH) 11 family and shares a sequence identity of approximately 32.0%-45.0% with fungal xylanases known to trigger plant immune responses. Treatment of Nicotiana benthamiana with purified CcXyn resulted in the induction of hypersensitive response (HR) and defence responses, such as the production of reactive oxygen species (ROS) and upregulation of defence gene expression, ultimately enhancing the resistance of N. benthamiana to Phytophthora nicotianae. These findings indicated that CcXyn functions as a microbe-associated molecular pattern (MAMP) elicitor for plant immune responses, independent of its enzymatic activity. Similar to fungal xylanases, CcXyn was recognized by the NbRXEGL1 receptor on the cell membrane of N. benthamiana. Downstream signalling was shown to be independent of the BAK1 and SOBIR1 co-receptors, indicating the involvement of other co-receptors in signal transduction following CcXyn recognition in N. benthamiana. Moreover, xylanases from other myxobacteria also demonstrated the capacity to trigger plant immune responses in N. benthamiana, indicating that xylanases in myxobacteria are ubiquitous in triggering plant immune functions. This study expands the understanding of xylanases with plant immune response-inducing properties and provides a theoretical basis for potential applications of myxobacteria in biocontrol strategies against phytopathogens.