MOLECULAR BREEDING OF DISEASE RESISTANT PLANTS WITH ARTIFICIAL CONTROL OF ACTIN RELATED GENE EXPRESSION

人工控制肌动蛋白相关基因表达的抗病植物分子育种

• 批准号: 11660045
• 负责人: KOBAYASHI Issei
• 金额: $ 2.43万
• 依托单位: MIE UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2000
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-11660045/
• 关键词: Rac small G-protein; PR-proteins; Salicylic acid; Defense responses; Transgenic plants; Tobacco; 細胞骨格; アクチン; Rac GTP結合タンパク質; 病害抵抗性; 環境ストレス耐性; 高等植物

Plant cells can respond to a variety of internal and external stimuli with rapid and dramatic rearrangements of their cytoplasm. These changes are often mediated by a dynamic cytoskeleton, the network of microtubules, actin microfilaments and their associated proteins. Because plants can't move themselves, quick responding capability taking from temporal and spatial control of cellular interior by the cytoskeleton must be essential to survive under changeable environment. We found the occurrence of dynamic reorganization of microfilaments during fungal invasion and evidenced the involvement of actin cytoskeleton in defense mechanism against fungal invasion, using several actin inhibitors. These results revealed the importance of temporal and spatial control of resistance machinery. Furthermore, the finding doesn't provide only new prospect of defense responses, but also new putative source of genetic engineering for improving crop plant. Recently, it has been known that Rho family smal … More l GTPases have emerged as key regulators of the actin cytoskeleton and, through their interaction with multiple target proteins. Little is known about Plant Rac function, but recent works suggest that some Rac isoforms may play a role in controlling cell division and polarization in tip growing pollen tubes. These results lead us to the hypothesis that plant Rac GTPases may be involved in reorganization of microfilaments and polarization of defense responses against fungal invasion. To investigate this hypothesis, we cloned tobacco Rac genes and overexpressed in tobacco plants. In Rac3 gene overexpressors, PR1a gene expressed spontaneously, whereas inducible expression was observed in the parent, SR-1. Increased sensitivity to BTH and enhanced expression of PR1a gene by inoculation of a nonpathogen was obtained in overexpressors. On the other hand, by wounding, no expression of PR1b was observed and spontaneous PR1a expression was suppressed. These results suggest that Rac may regulate both salicylate and jasmonate pathway in a defense signal transduction as a cross-talk regulator. Together all, we concluded that Rac genes are possible target for the genetic engeeniring of disease resistant plant. Less

植物细胞能够对各种内部和外部刺激做出反应，其细胞质发生迅速而戏剧性的重排。这些变化通常是由动态的细胞骨架、微管网络、肌动蛋白微丝及其相关蛋白介导的。由于植物本身不能移动，细胞骨架对细胞内部的时间和空间控制的快速反应能力是植物在多变的环境中生存所必需的。我们发现在真菌入侵过程中微丝发生了动态重组，并利用几种肌动蛋白抑制剂证明了肌动蛋白细胞骨架参与了抵御真菌入侵的防御机制。这些结果揭示了阻力机械的时间和空间控制的重要性。此外，这一发现不仅为防御反应提供了新的前景，而且也为改良作物提供了新的基因工程来源。最近，据了解，Rho家族的Smal…更多的L GTP酶已经成为肌动蛋白细胞骨架的关键调节因子，并通过它们与多个靶蛋白的相互作用而出现。植物RAC的功能知之甚少，但最近的工作表明，一些RAC亚型可能在控制顶端生长的花粉管的细胞分裂和极化方面发挥作用。这些结果使我们推测，植物RAC GTP酶可能参与微丝的重组和对真菌入侵的防御反应的极化。为了研究这一假说，我们克隆了烟草RAC基因，并在烟草中过表达。在rac3基因的过表达中，PR1a基因自发表达，而在亲本SR-1中观察到诱导表达。通过接种非病原菌，提高了对BTH的敏感性，增强了PR1a基因的表达。另一方面，伤后未观察到PR1b的表达，而PR1a的自发表达受到抑制。这些结果表明，在防御信号转导中，Rac可能作为串扰调节器同时调节水杨酸和茉莉酸途径。综上所述，Rac基因可能是抗病植物遗传工程的靶点。较少

项目成果

Kobayashi, I.: "Control of the responses to biotic stresses"The Actin Cytoskeleton in Plant Cells. Kluwer Academic Publishers. 573-585 (2000)

Kobayashi, I.：“控制对生物胁迫的反应”植物细胞中的肌动蛋白细胞骨架。

Kobayashi, I.: "Plant actin cytoskeletal responses to attack and invasion by pathogenic fungi."Plant Microtubules-Potential for Biotechnology. Springer Verlag. 83-101 (2000)

Kobayashi, I.：“植物肌动蛋白细胞骨架对病原真菌攻击和入侵的反应。”植物微管-生物技术的潜力。

Kobayashi,I.: "Plant actin cytoskeletal responses to attack and invasion by pathogenic fungi. In The Actin Cytoskeleton in Plant Cells (eds. by Baluska,F. et al.)"Kluwer Academic Publishers. 573-585 (2000)

Kobayashi，I.：“植物肌动蛋白细胞骨架对病原真菌攻击和入侵的反应。植物细胞中的肌动蛋白细胞骨架（Baluska，F. 等编辑）”Kluwer 学术出版社。

Kobayashi,I.: "Plant actin cytoskeletal responses to attack and invasion by pathogenic fungi. In The Actin Cytoskeleton in Plant Cells (eds. by Baluska, F.et al)"Kluwer Academic Publishers (In press). (2000)

Kobayashi,I.：“植物肌动蛋白细胞骨架对病原真菌攻击和入侵的反应。植物细胞中的肌动蛋白细胞骨架（Baluska，F.等人编辑）”Kluwer 学术出版社（正在出版）。

Kobayashi,I.: "Control of response to biotic stresses.In Plant Microtubules-Potential for Biotechnology.(ed.by Nick,P.)"Springer Verlag (In press). (2000)

Kobayashi,I.：“控制对生物胁迫的反应。植物微管-生物技术的潜力。（由 Nick,P. 编辑）”Springer Verlag（印刷中）。