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Wen, Y.-Q.

Publications and source records attributed to Wen, Y.-Q..

3 recordsLinked to original sources

An effector XopL enhances ethylene biosynthesis to promote Xanthomonas fragariae infection in strawberry

Xanthomonas fragariae (Xaf) is the cause for strawberry crown dry cavity rot and strawberry leaf angular spots. Despite having a long evolutionary history with strawberries, the plant-pathogen connection is poorly understood. Pathogenicity for the majority of plant pathogens is mostly dependent on the type-III secretion system, which introduces virulence type III effectors (T3Es) into eukaryotic hosts cells. For most of these T3Es, the subcellular targets are yet unclear. Here, We used the yeast-two-hybrid (Y2H) technique to construct an interaction network of strawberry-Xaf T3Es. Multiple T3Es were discovered to converge onto the strawberry 1-aminocyclopropane-1-carboxylic acid oxidases (ACOs), which are the last rate-limited step in the production of ethylene. We then concentrated on the connection between XopL and FveACO9. Strawberry plants that overexpressed XopL accumulated higher levels of ethylene and exhibited more severe Xaf infection. XopL boosted ethylene production by stabilizing the accumulation of FveACO9 protein and enhancing ACO enzyme activity. Additionally, strawberries treated with ACC or overexpressing FveACO9 were particularly vulnerable to Xaf infection. On the other hand, pre-treatment with -aminoinoisobutyric acid (AIB), an ACO inhibitor, effectively reduced Xaf infection. Our research indicates that Xaf utilizes a distinct approach to regulate the ethylene production of host plants in order to promote infection.

pathology↗

The Xanthomonas fragariae effector XopK suppresses stomatal immunity by perturbing abscisic acid signaling in strawberry

Xanthomonas fragariae (Xaf) usually causes angular leaf spot (ALS) in strawberry all over the world. Recently, we isolated a new strain of Xaf called Xaf YL19. This strain causes not only typical ALS symptoms, but also dry cavity rot in the crown tissues of strawberries. This was the first time a Xaf strain had both of these effects in strawberries. Pathogen effectors play a crucial role in plant colonization and infection. Understanding how effector proteins escape from plant surveillance is important for plant breeding and resistance deployment. In this study, thirty-three putative effectors were predicted in Xaf YL19, and a virulent secreted effector called XopK was identified. XopK has a robust capacity for suppressing plant cell death and transcript response to infection host. Transgenic strawberries expressing XopK exhibit more susceptibility to Xaf YL19, and this was associated with weakened stomatal immunity. Additionally abscisic acid (ABA) accumulation and signaling were mainly suppressed in the presence of XopK. XopK also inhibited ABA- and methyl jasmonate (MeJA)-induced stomatal closure, and ABA- but not MeJA-induced reactive oxygen species (ROS) production. Moreover, endogenous ABA is critical for Xaf-induced ROS burst and stomatal closure. These results suggested that Xaf YL19 uses XopK to suppress JA, especially ABA signaling, for disrupting stomatal closure, and allowing its colonization for disease development. Taken together, our results provide a novel virulent mechanism by Xaf and an available strategy for resistant breeding in strawberries.

pathology↗

VviWRKY10 and VviWRKY30 co-regulate powdery mildew resistance through modulating SA and ET-based defenses in grapevine

ABSRACTGrapevine is one of the most important economic fruit crops in the world. The widely cultivated grapevine (Vitis vinifera, Vvi) is susceptible to powdery mildew caused by Erysiphe necator. In this study, CRISPR-Cas9 was used to simultaneously knock out VviWRKY10 and VviWRKY30 encoding two transcription factors reported to be implicated in defense regulation. Fifty-three wrky10 (Vviwrky10 single mutant) transgenic plants and fifteen wrky10wrky30 (Vviwrky10Vviwrky30 double mutant) transgenic plants were generated. In a 2-year field evaluation of resistance to powdery mildew, the wrky10 showed strong resistance, while the wrky10wrky30 showed moderate resistance. Further analyses revealed that salicylic acid (SA) and reactive oxygen species (ROS) contents in the leaves of wrky10 and wrky10wrky30 were significantly increased, so did the ethylene (ET) content in the leaves of wrky10. The results from dual luciferase (DLUC) reporter assays, electrophoretic mobility shift assays (EMSA) and chromatin immunoprecipitation (ChIP)-qPCR assays demonstrated that VviWRKY10 could directly bind to the W-boxes in the promoter of VviEDS5-2, VviPR1, VviPR5 and VviRBOHD2 and inhibit their transcription, supporting its role as a negative regulator of SA-dependent defense. By contrast, VviWRKY30 could directly bind to the W-boxes in the promoter of VviACS3 and VviACS3L and promote their transcription, playing a positive role in ET production and ET-dependent defense. Moreover, VviWRKY10 and VviWRKY30 can bind to each others promoters and mutually inhibit each others transcription. Taken together, our results have revealed a complex mechanism of regulation by VviWRKY10 and VviWRKY30 for activation of measured and balanced defense responses against powdery mildew in grapevine. One-sentence summaryVviWRKY10 and VviWRKY30 play different roles in powdery mildew resistance through the salicylic acid and ethylene, respectively, and there is mutual inhibition between VviWRKY10 and VviWRKY30.

plant biology↗