Relative abundance of Δ5-sterols in plasma membrane lipids of root-tip cells correlates with aluminum tolerance of rice
Relative abundance of Δ5-sterols in plasma membrane lipids of root-tip cells correlates with aluminum tolerance of rice
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DOI：
10.1111/j.1399-3054.2008.01175.x
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发表时间：
2009-01-01
影响因子：
6.4
通讯作者：
Wagatsuma, Tadao
中科院分区：
文献类型：
--
作者：
Khan, M. Shahadat Hossain;Tawaraya, Keitarou;Wagatsuma, Tadao
我们调查了水稻植株中铝（Al）耐受性的变化，使用来自耐铝和广泛栽培的粳稻品种Sasanishiki家族的祖先品种。品种Rikuu-20是铝敏感的，而一个密切相关的品种，是Rikuu-20的后代，Rikuu-132，是耐铝。这两个品种进行了比较，以确定耐铝性的变化机制。敏感品种Rikuu-20表现出增加的质膜（PM）的渗透性和更大的Al处理1小时内的Al吸收。这不能用有机酸释放来解释。这些品种之间的PM的脂质组成不同，并可能占耐铝性的差异。耐受性品种Rikuu-132的磷脂与δ（5）-甾醇的比率低于敏感性品种Rikuu-20，表明Rikuu-132的PM比Rikuu-20的PM带更少的负电荷和更少的透性。我们使用Delta（5）-甾醇合成的抑制剂来改变两个品种中磷脂与Delta（5）-甾醇的比例。这些抑制剂降低了Rikuu-132及其耐铝祖先品种Kamenoo和Kyoku的耐铝性。此外，Rikuu-132显示出类似水平的铝敏感性时，磷脂与δ（5）-甾醇的比例增加，以匹配的Rikuu-20处理后，与烯效唑-P，obtusifoliol-14 α-脱甲基酶的抑制剂。这些结果表明，PM脂质组成是水稻品种耐铝性差异的一个因素。
We investigated variations in aluminum (Al) tolerance among rice plants, using ancestor cultivars from the family line of the Al-tolerant and widely cultivated Japonica cultivar, Sasanishiki. The cultivar Rikuu-20 was Al sensitive, whereas a closely related cultivar that is a descendant of Rikuu-20, Rikuu-132, was Al tolerant. These two cultivars were compared to determine mechanisms underlying variations in Al tolerance. The sensitive cultivar Rikuu-20 showed increased permeability of the plasma membrane (PM) and greater Al uptake within 1 h of Al treatment. This could not be explained by organic acid release. Lipid composition of the PM differed between these cultivars, and may account for the difference in Al tolerance. The tolerant cultivar Rikuu-132 had a lower ratio of phospholipids to Delta(5)-sterols than the sensitive cultivar Rikuu-20, suggesting that the PM of Rikuu-132 is less negatively charged and less permeabilized than that of Rikuu-20. We used inhibitors of Delta(5)-sterol synthesis to alter the ratio of phospholipids to Delta(5)-sterols in both cultivars. These inhibitors reduced Al tolerance in Rikuu-132 and its Al-tolerant ancestor cultivars Kamenoo and Kyoku. In addition, Rikuu-132 showed a similar level of Al sensitivity when the ratio of phospholipids to Delta(5)-sterols was increased to match that of Rikuu-20 after treatment with uniconazole-P, an inhibitor of obtusifoliol-14 alpha-demethylase. These results indicate that PM lipid composition is a factor underlying variations in Al tolerance among rice cultivars.