Molecular mechanism for establishment of basic compatibility in plant infection of pathogens producing host-specific toxins

产生宿主特异性毒素的病原体在植物感染中建立基本相容性的分子机制

• 批准号: 15380036
• 负责人: OTANI Hiroshi
• 金额: $ 10.05万
• 依托单位: Tottori University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15380036/
• 关键词: Host-specific toxin (HST); Protein HST; HST biosynthesis gene; Conditionally dispensable chromosome; Accessibility; Receptor; 蛋白質HST; 細胞融合; ハイブリッド株; 細胞壁; 葉緑体; たんぱく質HST; 遺伝子クラスター; 防御関連遺伝子; 病原菌受容化; 葉緑体シャペロニン; 毒素受容体

1.Detection of Pathogens Producing Host-Specific Toxins (HSTs) and Structure Determination of HSTsAlternaria brassicicola, the cause of black leaf spot of Brassica plants, produced a protein HST named AB-toxin only on host leaves. We found that an oligosaccharide for inducing AB-toxin production is released from host leaves after spore germination. Production of HST by germinating spores of pathogen mediated with host-derived factor is the first report. A.brassicae, the cause gray leaf spot of Brassica plants, is known to produce destruxin B as a HST, In this study, however, we found that toxicity of destruxin B is non-specific, and the pathogen produces new protein HST(s) different from destruxin B.2.Molecular Analysis of Pathogenicity in PatnogensA.alternata tomato pathotype, the cause Alternaria stem canker of tomato, produces HST named AAL-toxin. We isolated a HST biosynthesis gene, ALT1, whose product catalyzes the production of AAL-toxin in the pathogen. The ALT1 gene formed gene … More cluster involved in AAL-toxin biosynthesis of the pathogen. ALT1 was only present on the conditionally dispensable (CD) chromosomes in the pathogen suggesting acquisition by horizontal gene transfer.3.Molecular Analysis of Accessibility of Pathogens in PlantsA.alternata apple pathotype, the cause of Alternaria blotch of apple, produces a HST named AM-toxin. Because a single dominant gene controls susceptibility to the pathogen and AM-toxin in apple cultivars, we attempted to detect the susceptibility-related molecules. The results indicated that susceptibility of apple cultivars closely associates with SA60, a homolog of α-subunit (60α) of chloroplast chaperonin, and SA60 appears through a point mutation of chloroplast chaperonin 60α genes in resistant cultivars of apple. AM-toxin has a primary action site in chloroplasts of susceptible apple cultivars. Therefore, SA60 proteins may be a receptor for AM-toxin. On the other hand, tomato pathogens, A.alternata tomato pathotype and Corynespora cassiicola, the cause of Corynespora target spot of tomato, produce HSTs named AL-toxin and CCT toxin, respectively. Both pathogens were investigated for the sensitivity to α-tomatine, an antifungal substance in tomato. The results indicated that tomato pathogens detoxify α-tomatine in the infection process and that the detoxification is essential for colonization of the pathogens into tissues mediated by HSTs. Less

1.寄主专化毒素(HSTs)病原菌的检测及结构鉴定油菜黑斑病的病原菌油菜链格孢菌(Alternaria Brassicicola)只在寄主叶片上产生一种蛋白质HST，命名为AB-毒素。我们发现，在孢子萌发后，寄主叶片释放出一种诱导AB-毒素产生的寡糖。利用寄主衍生因子介导病原菌孢子萌发产生HST的报道尚属首次。引起十字花科植物灰斑病的甘蓝型油菜(A.brassicae)可以产生一种高活性链格孢菌素B，但在本研究中，我们发现该菌的毒性是非特异性的，并且会产生一种新的蛋白(S)。2.互隔交链孢霉致病力的分子分析。我们分离到一个HST生物合成基因ALT1，其产物催化病原菌中AAL-毒素的产生。Alt1基因形成基因…更多的簇参与了病原菌的AAL-毒素的生物合成。ALT1仅存在于病原菌的条件性可支配(CD)染色体上，提示是通过水平基因转移获得的。3.苹果赤星病病原菌可及性的分子分析苹果斑点落叶病的病原菌产生一种称为AM-毒素的HST。由于苹果品种对病原菌和AM-毒素的感受性由单个显性基因控制，因此我们尝试对感病相关分子进行检测。结果表明，苹果品种的感病与叶绿体伴侣蛋白α亚基(60α)的同源基因SA_(60)密切相关，抗性品种中的SA_(60)是通过叶绿体伴侣蛋白60α基因点突变产生的。AM-毒素在感病苹果品种的叶绿体中具有主要作用部位。因此，SA60蛋白可能是AM-毒素的受体。而引起番茄棒孢菌斑的病原菌--番茄病原菌、互隔交链孢菌型和棒孢霉--则分别产生AL-毒素和CCT毒素。研究了这两种病原菌对番茄抗真菌物质α-Tomatine的敏感性。结果表明，番茄病原菌在侵染过程中对α-Tomatine产生解毒作用，这种解毒作用是病原菌在HSTs介导下向组织内定植的必要条件。较少

项目成果

Host-specific AB-toxin production by germinating spores of Alternaria brassicicola is induced by a host-derived oligosaccharide

宿主来源的寡糖诱导芸苔链格孢萌发孢子产生宿主特异性 AB 毒素

• 发表时间: 2005
• 期刊: Physiological and Molecular Plant Pathology 66
• 作者: Oka;K.et al.
• 通讯作者: K.et al.

Molecular dissection of pathogenic strategies in plant fungal pathogens.

植物真菌病原体致病策略的分子解剖。

• 发表时间: 2004
• 期刊: Proceedings of International Joint Symposium between Korea and Japan
• 作者: Kodama;M. et al.
• 通讯作者: M. et al.

Hasegawa, M.: "Behavior of Erwinia ananas transformed with bioluminescence genes on rice plants"Journal of General Plant Pathology. 69. 267-270 (2003)

长谷川，M.：“用生物发光基因转化的菠萝欧文氏菌在水稻植物上的行为”普通植物病理学杂志。

Genomic and Genetic Analysis of Plant Parasitism and Defense Plants. "Conditionally dispensable chromosomes controlling pathogenicity of Alternaria alternata." (Ed.by Tsuyumu, S.et al.)

植物寄生和防御植物的基因组和遗传分析。

• 发表时间: 2004
• 作者: Tsuge;T. et al.
• 通讯作者: T. et al.

Aremu, E.A.: "Detection of fungi producing infection-inhibiting metabolites against Alternaria alternata Japanese pear pathotype from fungi inhabiting internal tissues of Japanese pear shoots"Journal of General Plant Pathology. 70(In press). (2004)

Aremu，E.A.：“从居住在日本梨枝条内部组织的真菌中检测产生针对链格孢日本梨致病型的感染抑制代谢物的真菌”普通植物病理学杂志。