Journal of Fungi
·
2025
·Vol. 11
·期 1
·73
·
IF 4
Jinyao Yin,Xuehuan Zhu,Yalong Chen,Yanyang Lv,Jiaxin Shan,Yuhan Liu,Wenbo Liu,Weiguo Miao,Xiao Li
The exocyst complex in eukaryotic cells modulates secretory vesicle transportation to promote exocytosis. The exocyst is also required for the hyphal growth and pathogenic development of several filamentous phytopathogens. Obligate biotrophic powdery mildew fungi cause considerable damage to many cash crops; however, the exocyst’s roles in this group of fungi is not well studied. To verify the functions of the exocyst in powdery mildew fungus, we identified two exocyst subunits, EqSec5 and EqSec6, fromErysiphe quercicola, a powdery mildew fungus that infects the rubber treeHevea brasiliensis. When GFP-fused EqSec5 and EqSec6 were introduced intoE. quercicolaand another phytopathogenic fungus,Magnaporthe oryzae, they primarily localized to the hyphal tip region. Inducing gene silencing ofEqSec5orEqSec6caused growth and infection defects, and those defects could not be fully restored under the NADPH oxidase inhibitor treatment to the plant. The silenced strains also induced the host defense response including reactive oxygen species accumulation and callose deposition. The silencing ofEqSec5orEqSec6also inhibited the secretion of the effector protein EqIsc1, interrupting plant salicylic acid biosynthesis. Yeast two-hybrid and gene overexpression assays suggested that EqSec5 and EqSec6 interact with each other and can complement each other’s function during host infection. Overall, our study provides evidence that the exocyst in this powdery mildew fungus facilitates effector secretion, hyphal growth, and infection.
研究领域:
植物病理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MOLECULAR PLANT PATHOLOGY
·
2024
·Vol. 25
·期 11
·e70030
·
IF 4.8
Jinyao Yin,Xiao Li,Linpeng Dong,Xuehuan Zhu,Yalong Chen,Wenyuan Zhao,Yuhan Liu,Jiaxin Shan,Wenbo Liu,Chunhua Lin,Weiguo Miao
Obligate biotrophic powdery mildew fungi infect a wide range of economically important plants. These fungi often deliver effector proteins into the host tissues to suppress plant immunity and sustain infection. The phytohormone salicylic acid (SA) is one of the most important signals that activate plant immunity against pathogens. However, how powdery mildew effectors interact with host SA signalling is poorly understood. Isochorismatase (ISC) effectors from two other filamentous pathogens have been found to inhibit host SA biosynthesis by hydrolysing isochorismate, the main SA precursor in the plant cytosol. Here, we identified an ISC effector, named EqIsc1, from the rubber tree powdery mildew fungus Erysiphe quercicola . In ISC enzyme assays, EqIsc1 displayed ISC activity by transferring isochorismate to 2,3-dihydro-2,3-dihydroxybenzoate in vitro and in transgenic Nicotiana benthamiana plants. In EqIsc1-expressing transgenic Arabidopsis thaliana , SA biosynthesis and SA-mediated immune response were significantly inhibited. In addition, we developed an electroporation-mediated transformation method for the genetic manipulation of E. quercicola . Inoculation of rubber tree leaves with EqIsc1 -silenced E. quercicola strain induced SA-mediated immunity. We also detected the translocation of EqIsc1 into the plant cytosol during the interaction between E. quercicola and its host. Taken together, our results suggest that a powdery mildew effector functions as an ISC enzyme to hydrolyse isochorismate in the host cytosol, altering the SA biosynthesis and immune response.
研究领域:
植物病理学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Phytopathology Research
·
2025
·Vol. 7
·期 1
·1-18
·
IF 3.5
Shan Jiaxin,Su Fan,Yin Jinyao,Liu Yuhan,Zhu Xuehuan,Zuo Minghao,Liu Wenbo,Lin Chunhua,Li Xiao,Miao Weiguo
Phytopathogens secrete effector proteins that disrupt plant immunity. Phytohormones, such as ethylene, function as immune signals that regulate plant responses to phytopathogens. However, the mechanisms by which powdery mildew fungi utilize effectors to manipulate ethylene signaling remain poorly understood. This study reports that Eae1, an effector from the powdery mildew fungus Erysiphe quercicola , can reduce ethylene levels and attenuate the immune response in rubber trees ( Hevea brasiliensis ), thereby promoting fungus infection. Notably, Eae1 shares homologs with effectors from other powdery mildew fungi. Our findings indicate that the Eae1 transcription can be induced by enhanced ethylene signaling. Eae1 is translocated to plant chloroplasts, where it destabilizes Hevea brasiliensis S-adenosyl-L-methionine synthetase, a key enzyme in ethylene biosynthesis, leading to reduced ethylene production. The chloroplast-localized protein Toc159/AIG1 (AIG1) may facilitate this interaction. Overall, our study reveals a mechanism by which powdery mildew fungi disrupt ethylene-mediated resistance in host plants.
研究领域:
植物病理学
·
分子植物-微生物互作
·
植物激素信号
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微生物效应子生物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）