A 9-cis-epoxycarotenoid dioxygenase inhibitor for use in the elucidation of abscisic acid action mechanisms
A 9-cis-epoxycarotenoid dioxygenase inhibitor for use in the elucidation of abscisic acid action mechanisms
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DOI：
10.1016/j.bmc.2006.04.025
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发表时间：
2006-08-15
影响因子：
3.5
通讯作者：
Asami, Tadao
中科院分区：
文献类型：
--
作者：
Kitahata, Nobutaka;Han, Sun-Young;Asami, Tadao
植物激素脱落酸（ABA）响应于干旱胁迫而积累并赋予植物胁迫耐受性。9-顺式环氧类胡萝卜素双加氧酶（NCED）是ABA合成途径中的关键调控酶，在ABA积累过程中起着重要作用。用第一个被鉴定的NCED抑制剂阿巴明处理植物，抑制ABA的积累。在对阿巴明构效关系研究的基础上，我们鉴定了一种比阿巴明更有效的ABA积累抑制剂，并将其命名为阿巴明SG。abamineSG的一个重要结构特征是甲酯和氮原子之间的三碳连接基。与对照相比，100 μ M abamineSG处理逆境胁迫植株抑制ABA积累77%，而abamine抑制ABA积累35%。ABAMINESG处理的植株在渗透胁迫下ABA反应基因和ABA分解代谢基因的表达受到强烈抑制。AbamineSG是酶NCED的竞争性抑制剂，Ki为18.5 μ M。虽然高浓度（> 50 μ M）的abamineSG抑制拟南芥幼苗的生长，但这种作用与ABA生物合成的抑制无关，100 μ M的abamineSG对幼苗生长没有影响。这些结果表明，abamineSG是一个比abamine更有效和特异的ABA生物合成抑制剂。(c)2006爱思唯尔有限公司保留所有权利。
The plant hormone abscisic acid (ABA) accumulates in response to drought stress and confers stress tolerance to plants. 9-cis-Epoxycarotenoid dioxygenase (NCED), the key regulatory enzyme in the ABA biosynthesis pathway, plays an important role in ABA accumulation. Treatment of plants with abamine, the first NCED inhibitor identified, inhibits ABA accumulation. On the basis of structure-activity relationship studies of abamine, we identified an inhibitor of ABA accumulation more potent than abamine and named it abamineSG. An important structural feature of abamineSG is a three-carbon linker between the methyl ester and the nitrogen atom. Treatment of osmotically stressed plants with 100 mu M abamineSG inhibited ABA accumulation by 77% as compared to the control, whereas abamine inhibited the accumulation by 35%. The expression of AB A-responsive genes and ABA catabolic genes was strongly inhibited in abamineSG-treated plants under osmotic stress. AbamineSG is a competitive inhibitor of the enzyme NCED, with a Ki of 18.5 mu M. Although the growth of Arabidopsis seedlings was inhibited by abamine at high concentrations (> 50 mu M), an effect that was unrelated to the inhibition of ABA biosynthesis, seedling growth was not affected by 100 mu M abamineSG. These results suggest that abamineSG is a more potent and specific inhibitor of ABA biosynthesis than abamine. (c) 2006 Elsevier Ltd. All rights reserved.