Transgenic plants of creeping bent grass harboring the stress inducible gene, 9-cis-epoxycarotenoid dioxygenase, are highly tolerant to drought and NaCl stress
Transgenic plants of creeping bent grass harboring the stress inducible gene, 9-cis-epoxycarotenoid dioxygenase, are highly tolerant to drought and NaCl stress
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DOI：
10.1007/s10725-005-3380-6
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发表时间：
2005-11-01
影响因子：
4.2
通讯作者：
Kim, DH
中科院分区：
文献类型：
--
作者：
Aswath, CR;Kim, SH;Kim, DH
利用农杆菌介导的方法，将从豇豆中克隆的与脱落酸（阿坝）合成相关的9-顺式环氧类胡萝卜素双加氧酶（9-cis-epoxycarotenoid dioxygenase，9-cis-epoxycarotenoid dioxygenase，9-cis-epoxycarotenoid dioxygenase，9-cis-epoxycarotenoid）具有同源性的VuNCED 1基因导入匍匐翦股颖，获得转基因植株。阿坝是类胡萝卜素的裂解产物，参与植物的胁迫反应。植物中阿坝生物合成的限制步骤可能是9-顺式-环氧类胡萝卜素的裂解，这是阿坝生物合成的第一个关键步骤。通过Southern杂交基因组DNA-PCR进行的转基因系的分子分析揭示了VuNCED 1的整合。通过将转基因植物暴露于盐胁迫（高达10 dS m（-1））和水分胁迫（高达75%）10周进行的挑战研究显示，超过50%的转基因植物可以在NaCl和干旱胁迫下存活，而野生型不能。在干旱和正常条件下测定了阿坝水平，干旱和NaCl胁迫显著增加了转基因植株内源阿坝水平。这些结果表明，有可能操纵阿坝水平在植物中过表达的关键调控基因在阿坝生物合成和胁迫耐受性可以提高通过增加阿坝水平。
Transgenic lines of creeping bent grass were generated by Agrobacterium-mediated transformation with the VuNCED1 which was cloned from cow pea has a homology to 9-cis-epoxycarotenoid dioxygenase, which is supposed to be involved in abscisic acid (ABA) biosynthesis. ABA, a cleavage product of carotenoids, is involved in stress responses in plants. The limiting step of ABA biosynthesis in plants is presumably the cleavage of 9-cis-epoxycarotenoids, the first committed step of ABA biosynthesis. Molecular analyses of transgenic lines as performed by Southern hybridization genomic DNA-PCR revealed integration of the VuNCED1. Challenge studies performed with transgenic plants by exposure to salt stress (up to 10 dS m(-1)) and water stress (up to 75%) for 10 weeks, revealed that more than 50% of the transgenic plants could survive NaCl and drought stress whereas wild-type was not. ABA levels were measured under drought and normal conditions, endogenous ABA was dramatically increased by drought and NaCl stress in transgenic plants. These results indicate that it is possible to manipulate ABA levels in plants by over expressing the key regulatory gene in ABA biosynthesis and that stress tolerance can be improved by increasing ABA levels.