花生抗黄曲霉菌产毒机制的研究
发布时间：2019-02-16 21:50
【摘要】：花生(Arachis hypogaea L.)是我国重要的油料与经济作物之一,总产量和总产值均已跃居国产油料作物的首位,且其单位面积产量和产油量高、种植效益好、国际竞争力强,发展花生生产对于保障植物油脂和蛋白质供给、提高农业生产效益、增加农民收入具有重要作用。然而,黄曲霉毒素污染严重危及花生及其制品的食用安全性、消费者健康和国际贸易,是制约花生产业持续发展的关键风险因子。培育抗黄曲霉花生品种是防控毒素污染最为经济有效的措施,而系统开展花生抗黄曲霉菌产毒机制的研究则是深化这一抗性遗传改良的基础。花生对黄曲霉菌产毒的抗性(抗产毒)是应答黄曲霉菌侵害的主动防御反应,探讨和揭示抗产毒机制具有重要的理论意义和实用价值。本研究利用典型的抗产毒花生品种中花6号(抗)和高产毒品种中花12(感),利用转录组测序技术,首次比较了抗、感花生应答黄曲霉菌产毒的基因表达差异,分析了黄曲霉菌与抗、感花生互作的基因表达差异,探讨了白藜芦醇与花生抗产毒的关系及其抑制黄曲霉毒素合成的分子机制。主要结论如下。1、明确了典型抗、感花生成熟种子应答黄曲霉菌产毒的基因表达变化及差异。受黄曲霉菌侵染后,抗、感花生种子中均有大量基因的表达发生了改变,其中表现上调表达的差异基因比下调表达的多。与高产毒花生相比,抗产毒花生能迅速启动较多防卫反应来抵御黄曲霉菌的产毒,其中病程相关蛋白(PR-1、PR-2、PR-5、PR-10)、转录因子(WRKY、bZIP、ERF)和类苯基丙烷(PAL、C4H、4CL、STS、CHS)等抗性相关基因上调表达水平高,且维持高水平表达的时间较长。2、首次以寄生于花生种子组织内的黄曲霉菌为研究对象,明确了抗产毒花生能有效抑制黄曲霉毒素合成相关基因的表达。黄曲霉菌在侵染高产毒花生中花12的过程中,与菌丝穿透力(faeC、abfB、mndA、pgxC)、分生孢子形成(RodA/RolA、AtfA、Con-6、Con-10、Pks P)和黄曲霉毒素合成(aflD、aflX、aflNa)等相关基因表现出显著上调表达,而在侵染抗产毒中花6号的过程中,这些基因的表达都受到了显著抑制,从而有效抑制了其定殖与摄取营养物质的能力及毒素合成前体物质的供应,表明中花6号具有抑制黄曲霉菌定殖、生长和黄曲霉毒素合成的主动抗性反应。3、通过离体处理,发现白藜芦醇能直接抑制黄曲霉毒素合成关键基因aflA和aflB的表达,限制毒素合成前体物质的供应;能提高超氧化物歧化酶基因的表达,减少氧胁迫对毒素合成的促进作用;能使stuA、fluG和flbC等分生孢子形成相关基因显著下调表达,减少分生孢子的形成和再侵染机率。结合白藜芦醇与花生产毒抗性的相关性分析,证实了中花6号白藜芦醇含量高是其产毒抗性强的重要机制之一。
[Abstract]:Peanut (Arachis hypogaea L.) It is one of the important oil crops and cash crops in China. The total yield and total output value have leapt to the first place of the domestic oil crops, and its unit area yield and oil yield are high, the planting benefit is good, and the international competitiveness is strong. The development of peanut production plays an important role in ensuring the supply of vegetable oil and protein, improving the benefit of agricultural production and increasing farmers' income. However aflatoxin pollution seriously endangers the edible safety of peanut and its products consumer health and international trade are the key risk factors restricting the sustainable development of peanut industry. Cultivation of peanut varieties resistant to Aspergillus flavus is the most economical and effective measure to prevent and control toxin pollution, and systematic study on the mechanism of resistance to Aspergillus flavus is the basis for further genetic improvement of this resistance. Peanut resistance to Aspergillus flavus is an active defense response in response to Aspergillus flavus. It is of great theoretical significance and practical value to explore and reveal the mechanism of resistance to Aspergillus flavus. In this study, the difference of gene expression in resistance to and response to Aspergillus flavus production in peanut was first compared by using transcription sequencing technique, using typical varieties Zhonghua 6 (resistance) and Zhonghua 12 (sense), which were resistant to toxin production in peanut and Zhonghua 12, respectively. The difference of gene expression between Aspergillus flavus and resistant and susceptible peanut was analyzed. The relationship between resveratrol and antitoxic effect of peanut and the molecular mechanism of inhibiting aflatoxin synthesis were discussed. The main conclusions are as follows: 1. The variation and difference of gene expression in response to Aspergillus flavus in typical resistant and susceptible peanut seeds were identified. After being infected by Aspergillus flavus, a large number of genes expressed in resistant and susceptible peanut seeds changed, among which more differentially expressed genes showed up-regulated than down-regulated ones. Compared with high-yielding peanut, resistant toxigenic peanut can initiate more defense response to resist aflatoxin, including course related protein (PR-1,PR-2,PR-5,PR-10) and transcription factor (WRKY,bZIP,). ERF) and phenylpropanoid (PAL,C4H,4CL,STS,CHS) genes were up-regulated and maintained for a long time. 2. Aspergillus flavus, which was parasitic in peanut seed tissue, was studied for the first time. It is clear that antitoxic peanut can effectively inhibit the expression of aflatoxin related genes. Aspergillus flavus is associated with hyphal penetration (faeC,abfB,mndA,pgxC), conidial formation (RodA/RolA,AtfA,Con-6,Con-10,Pks P) and aflatoxin synthesis (aflD,aflX,) in the process of infecting high-yielding peanut Flower 12 with mycelium penetration (faeC,abfB,mndA,pgxC), conidia formation (RodA/RolA,AtfA,Con-6,Con-10,Pks P) and aflatoxin synthesis (aflD,aflX,). AflNa and other related genes showed a significant up-regulation of expression, and the expression of these genes was significantly inhibited during the infection of the drug-resistant Zhonghua 6. Therefore, the ability of colonization and uptake of nutrients and the supply of precursor substances for toxin synthesis were effectively inhibited, indicating that Zhonghua 6 had an active resistance response to inhibit the colonization, growth and aflatoxin synthesis of Aspergillus flavus. It was found that resveratrol could directly inhibit the expression of aflA and aflB, and restrict the supply of precursor to aflatoxin synthesis. It can increase the expression of superoxide dismutase gene and reduce the effect of oxygen stress on toxin synthesis, and can significantly down-regulate the expression of conidial formation related genes such as stuA,fluG and flbC, and reduce the probability of conidia formation and re-infection. Combined with the correlation analysis between resveratrol and floral toxicity resistance, it was proved that the high content of resveratrol in Zhonghua 6 was one of the important mechanisms of its strong toxic resistance.
【学位授予单位】：中国农业科学院
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S565.2
本文编号：2424869
[Abstract]:Peanut (Arachis hypogaea L.) It is one of the important oil crops and cash crops in China. The total yield and total output value have leapt to the first place of the domestic oil crops, and its unit area yield and oil yield are high, the planting benefit is good, and the international competitiveness is strong. The development of peanut production plays an important role in ensuring the supply of vegetable oil and protein, improving the benefit of agricultural production and increasing farmers' income. However aflatoxin pollution seriously endangers the edible safety of peanut and its products consumer health and international trade are the key risk factors restricting the sustainable development of peanut industry. Cultivation of peanut varieties resistant to Aspergillus flavus is the most economical and effective measure to prevent and control toxin pollution, and systematic study on the mechanism of resistance to Aspergillus flavus is the basis for further genetic improvement of this resistance. Peanut resistance to Aspergillus flavus is an active defense response in response to Aspergillus flavus. It is of great theoretical significance and practical value to explore and reveal the mechanism of resistance to Aspergillus flavus. In this study, the difference of gene expression in resistance to and response to Aspergillus flavus production in peanut was first compared by using transcription sequencing technique, using typical varieties Zhonghua 6 (resistance) and Zhonghua 12 (sense), which were resistant to toxin production in peanut and Zhonghua 12, respectively. The difference of gene expression between Aspergillus flavus and resistant and susceptible peanut was analyzed. The relationship between resveratrol and antitoxic effect of peanut and the molecular mechanism of inhibiting aflatoxin synthesis were discussed. The main conclusions are as follows: 1. The variation and difference of gene expression in response to Aspergillus flavus in typical resistant and susceptible peanut seeds were identified. After being infected by Aspergillus flavus, a large number of genes expressed in resistant and susceptible peanut seeds changed, among which more differentially expressed genes showed up-regulated than down-regulated ones. Compared with high-yielding peanut, resistant toxigenic peanut can initiate more defense response to resist aflatoxin, including course related protein (PR-1,PR-2,PR-5,PR-10) and transcription factor (WRKY,bZIP,). ERF) and phenylpropanoid (PAL,C4H,4CL,STS,CHS) genes were up-regulated and maintained for a long time. 2. Aspergillus flavus, which was parasitic in peanut seed tissue, was studied for the first time. It is clear that antitoxic peanut can effectively inhibit the expression of aflatoxin related genes. Aspergillus flavus is associated with hyphal penetration (faeC,abfB,mndA,pgxC), conidial formation (RodA/RolA,AtfA,Con-6,Con-10,Pks P) and aflatoxin synthesis (aflD,aflX,) in the process of infecting high-yielding peanut Flower 12 with mycelium penetration (faeC,abfB,mndA,pgxC), conidia formation (RodA/RolA,AtfA,Con-6,Con-10,Pks P) and aflatoxin synthesis (aflD,aflX,). AflNa and other related genes showed a significant up-regulation of expression, and the expression of these genes was significantly inhibited during the infection of the drug-resistant Zhonghua 6. Therefore, the ability of colonization and uptake of nutrients and the supply of precursor substances for toxin synthesis were effectively inhibited, indicating that Zhonghua 6 had an active resistance response to inhibit the colonization, growth and aflatoxin synthesis of Aspergillus flavus. It was found that resveratrol could directly inhibit the expression of aflA and aflB, and restrict the supply of precursor to aflatoxin synthesis. It can increase the expression of superoxide dismutase gene and reduce the effect of oxygen stress on toxin synthesis, and can significantly down-regulate the expression of conidial formation related genes such as stuA,fluG and flbC, and reduce the probability of conidia formation and re-infection. Combined with the correlation analysis between resveratrol and floral toxicity resistance, it was proved that the high content of resveratrol in Zhonghua 6 was one of the important mechanisms of its strong toxic resistance.
【学位授予单位】：中国农业科学院
【学位级别】：博士
【学位授予年份】：2016
【分类号】：S565.2
【参考文献】
相关期刊论文 前3条
1 洪彦彬;李少雄;刘海燕;周桂元;陈小平;温世杰;梁炫强;;SSR标记与花生抗黄曲霉性状的关联分析[J];分子植物育种;2009年02期
2 周桂元,梁炫强;花生种子抗黄曲霉侵染性状遗传控制的研究[J];花生学报;2001年03期
3 梁炫强,潘瑞炽,宾金华;花生收获前黄曲霉侵染因素研究[J];中国油料作物学报;2000年04期
相关博士学位论文 前2条
1 张初署;中国四个生态区花生土壤中黄曲霉菌分布、产毒特征及遗传多样性研究[D];中国农业科学院;2013年
2 丁小霞;中国产后花生黄曲霉毒素污染与风险评估方法研究[D];中国农业科学院;2011年
，本文编号：2424869
本文链接：https://www.wllwen.com/shoufeilunwen/nykjbs/2424869.html
