Fungal Biology
·
2018
·
IF 2.571
Zhi Li,He Zhang,Guohuai Li
Lasiodiplodia theobromae , a phytopathogenic fungus that causes peach gummosis , is considered one of the major constraints to peach production worldwide. Here, we report the characteristics of toxic metabolites and the proteomics investigation of the secreted proteins of L. theobromae from its in vitro culture. The phytotoxins of L. theobromae from the culture filtrate of Richard’s liquid medium showed high toxicity on peach current year shoots with large lesion diameter and high gum weight. The toxicity measurement showed that 23.6 and 21.2 mg gum were induced from peach shoots by solvent fractions of ethyl acetate and dichloromethane, respectively, with significant differences from other organic solvents. A total of 23 proteins were identified by liquid chromatography–mass spectrometry from the in vitro secretome of L. theobromae . Sequence analysis indicated that 14 proteins were extracellular proteins based on signal peptides and localization. The expression profiles of the analyzed fungal genes were significantly upregulated from 1 day postinoculation (dpi) to 2 dpi, indicating that the early stage is an important stage for the infection of L. theobromae . The present study has provided insights into the extracellular phytotoxins and secreted proteins that are possibly associated with pathogenicity of the peach gummosis.
研究领域:
植物病理学
·
分子生物学
·
蛋白质组学
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产品关联
DOI
PubMed
高影响因子
PHYTOPATHOLOGY
·
2023
·
IF 3.2
Mr. Jiayu Yin,Ms. Shuang Wu,Ms. Yongli Yang,Dr. Delu Wang,Prof. Yue Ma,Dr. Yongtian Zhao,Prof. Sujitraj Sheth,Miss Honglin Huang,Dr. Baoan Song,Dr. Zhuo Chen
Carvacrol expresses a wide range of biological activities, but the studies of its mechanisms focused on bacteria, mainly involving the destruction of the plasma membrane. In this study, carvacrol exhibited strong antifungal activities against several phytopathogenic fungi and determined a novel antifungal mechanism against Lasiodiplodia theobromae. RNA sequencing indicated that many genes of L. theobromae hyphae were predominately induced by carvacrol, particularly those involved in replication and transcription. Hyperchromic, hypsochromic, and bathochromic effects in the UV-visible absorption spectrum were observed following titration of calf thymus DNA (ctDNA) and carvacrol, which indicated the formation of a DNA–carvacrol complex. Circular dichroism (CD) spectroscopy indicated the response of DNA to carvacrol was similar to 4’, 6-diamidino-2-phenylindole (DAPI), but different from that of ethidium bromide (EB), implying the ionic bonds between carvacrol and ctDNA. Fluorescence spectrum (FS) analysis indicated that carvacrol quenched the fluorescence of double-stranded DNA more than single-stranded DNA, indicating that carvacrol mainly bound to double-stranded DNA. A displacement assay showed that carvacrol reduced the fluorescence intensity of the DNA–DAPI complex through competing with DAPI, but this did not occur for DNA–EB. FS assay revealed that carvacrol bound to AAA sequence on the minor groove of ds-oligonucleotides. The hydroxyl of carvacrol was verified to bind to ctDNA through a comparative test in which structural analogs of carvacrol, including thymol, 4-ethyl-1,2-dimethyl, etc. were analyzed. The current study indicated carvacrol can destruct plasma membranes and bind to the minor groove of DNA, which inhibited the fungal proliferation by disturbing the stability of dsDNA.
研究领域:
植物病理学
·
分子生物学
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DOI
高影响因子
MOLECULAR PLANT-MICROBE INTERACTIONS
·
2021
·
IF 4.171
Xingtao Bao,Rui Yang,Shilong Jiang,Jinping Zhao,Delu Wang,Dongxue Li,Xian Wu,Baoan Song,Zhuo Chen
Diseases caused by fungi can affect the quality and yield of the leaves of tea [ Camellia sinensis (L.) Kuntze]. At present, the availability of highly effective and safe fungicides for controlling tea plants remains limited. The objectives of this study were to identify novel compounds with antifungal activities and to determine their molecular mechanisms. A series of sulfone compounds containing 1,3,4-oxadiazole were evaluated in China for their antifungal activities against several pathogens causing foliar diseases and high production losses. Transcriptomics and bioinformatics were used to analyze the differentially expressed genes of Lasiodiplodia theobromae treated with a representative compound, jiahuangxianjunzuo (JHXJZ). Moreover, the effects of JHXJZ on ergosterol content, membrane permeability, cell structure, and seven key genes involved in the ergosterol biosynthetic pathway were investigated. JHXJZ had a strong antifungal activity against L. theobromae in vitro, with an effective concentration giving 50% inhibition of 3.54 ± 0.55 μg/ml, and its curative efficacies on detached tea leaves reached 41.78% at 100 μg/ml. JHXJZ upregulated 899 genes ( P < 0.05) and downregulated 1,185 genes ( P < 0.05) in L. theobromae . These genes were found to be associated with carbohydrate metabolic processes, which are closely related to steroid biosynthesis in the Kyoto Encyclopedia of Genes and Genomes pathways. Because JHXJZ regulates the key genes of sterol biosynthesis, it decreased the ergosterol content, increased cell-membrane permeability, changed the cellular structure, enhanced the roughness of the surface of the hyphae, and resulted in degradation of the hyphal nuclei and necrosis of the hyphal cytoplasm. Our study demonstrates that JHXJZ is a fungicide with a novel mechanism of action that differs from that of triazole fungicides. JHXJZ has potential for applications in controlling tea plant diseases.
研究领域:
植物病理学
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分子生物学
·
杀菌剂开发
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产品关联
DOI
PubMed
高影响因子
PLANT PATHOLOGY
·
2014
·Vol. 63
·期 6
·1306-1315
·
IF 2.969
Z. Li,W. Zhu,Y.-C. Fan,J.-L. Ye,G.-H. Li
Peach gummosis, caused by Botryosphaeria spp. fungi, is the process of gum accumulation and exudation in plants. Ethephon (2-chloroethylphosphonic acid) has profound effects on plants, including enhanced production of secondary metabolites and regulation of plant diseases. This study investigates the effects of application of ethephon before and after inoculation with Lasiodiplodia theobromae on gum formation. Gum formation was promoted by ethephon treatment prior to pathogen inoculation, but inhibited by ethephon applied after the pathogen. The inhibitory effect was counteracted by 1-methylcyclopropane, which is an ethylene signal inhibitor. 1-methylcyclopropane also promoted gum formation. Exposure of three isolates of Botryosphaeria to ethephon inhibited mycelial growth. Both treatment methods increased the sugar content at 12 and 24 h post-inoculation (hpi). However, the sucrose, glucose and fructose contents were significantly higher in shoots with ethephon post-treatment (application of ethephon after the pathogen inoculation) than those in shoots with ethephon pre-treatment (application of ethephon prior to pathogen inoculation) at 48 and 72 hpi. The expression of two putative senescence-related genes, SEN2 and SEN4 , were significantly enhanced in pre- and post-treated shoots with ethephon at 24, 48 and 72 hpi. Ethephon application also up-regulated expression of the pathogenesis-related protein PR4 while down-regulating PR1a and PR10. The results show that ethephon has a dual function in regulating gum formation by affecting both the peach shoots and the pathogen.
研究领域:
植物病理学
·
分子生物学
·
植物生理学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）