Nitric oxide, polyamines and Cd-induced phytotoxicity in wheat roots
Nitric oxide, polyamines and Cd-induced phytotoxicity in wheat roots
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DOI：
10.1016/j.phytochem.2008.07.016
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发表时间：
2008-10-01
期刊：
影响因子：
3.8
通讯作者：
Benavides, M. P.
中科院分区：
文献类型：
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作者：
Groppa, M. D.;Rosales, E. P.;Benavides, M. P.
为了进一步探讨镉毒害小麦幼苗的生化基础，我们研究了一氧化氮（NO）和多胺作为信号分子参与金属诱导的根生长抑制的可能作用。当使用在0.1 mM，硝普钠，NO-释放化合物，抑制根生长到类似的程度，镉和提高多胺含量镉也没有。腐胺和亚精胺处理引起根生长的显着下降，精胺给予最大程度的抑制（减少77%）。同时加入镉和腐胺生物合成抑制剂（DFMA和DFMO）防止腐胺水平的增加，但没有恢复正常的根生长。NO含量，证明了荧光探针DAF-FM二乙酸酯，被发现显着增加，在镉和多胺处理的植物，特别是在那些暴露于精胺的根。该效应对NO是特异性的，因为NO清除剂cPTIO几乎抑制荧光信号。在根系的氧化状态方面，只有镉和精胺增强了根系的脂质过氧化作用。与此同时，所有处理均导致非酶抗氧化防御谷胱甘肽水平显着增加。我们的研究结果强烈表明，镉和精胺处理诱导小麦根中NO的形成，反过来，参与根生长抑制。(C)2008爱思唯尔有限公司保留所有权利。
To further explore the biochemical basis of Cd toxicity in developing wheat seedlings, we studied the possible role of nitric oxide (NO) and polyamines as signaling molecules involved in metal-induced root growth inhibition. When used at 0.1 mM, sodium nitroprusside, a NO-releasing compound, inhibited root growth to a similar extent as Cd and enhanced the polyamine contents as Cd also did. Putrescine and spermidine treatments caused significant decreases in root growth with spermine giving the greatest level of inhibition (77% reduction). The simultaneous addition of Cd and inhibitors of putrescine biosynthesis (DFMA and DFMO) prevented increases in putrescine levels but did not restore normal root growth. NO content, as evidenced by the fluorescent probe DAF-FM diacetate, was found to be significantly increased in the roots of both Cd and polyamine treated plants, especially in those exposed to spermine. The effect was specific for NO since the NO scavenger cPTIO almost suppressed the fluorescent signal. Concerning the oxidative status of the root system, only Cd and spermine enhanced lipid peroxidation in roots. At the same time, all treatments led to a significant increase in levels of the non-enzymatic antioxidant defense glutathione. Our results strongly suggest that Cd and spermine treatments induce NO formation in wheat roots which, in turn, is involved in root growth inhibition. (C) 2008 Elsevier Ltd. All rights reserved.