Auxin enhances aluminum-induced citrate exudation through upregulation of GmMATE and activation of the plasma membrane H+-ATPase in soybean roots
Auxin enhances aluminum-induced citrate exudation through upregulation of GmMATE and activation of the plasma membrane H+-ATPase in soybean roots
复制标题
生长素通过上调 GmMATE 和激活大豆根质膜 H -ATP 酶增强铝诱导的柠檬酸渗出
DOI：
10.1093/aob/mcw133
复制
发表时间：
2016
期刊：
影响因子：
4.2
通讯作者：
Qi Chen
中科院分区：
文献类型：
--
作者：
Ping Wang;Wenqian Yu;Jiarong Zhang;Zed Rengel;Jin Xu;Qinqin Han;Limei Chen;Kunzhi Li;Yongxiong Yu;Qi Chen
背景与目的铝毒是酸性土壤中植物生长和作物生产的限制因子。柠檬酸的分泌和质膜H ~+-ATPase的激活参与了大豆对铝胁迫的响应。生长素在植物生长和逆境反应中具有重要作用。然而，很少有人知道铝胁迫下生长素和柠檬酸分泌之间可能的相互作用。本研究以大豆为材料，通过测定大豆根系中IAA含量、铝浓度、柠檬酸分泌量、质膜H+-ATPase活性、相关基因的表达和质膜H+-的磷酸化本研究以水培大豆为材料，通过整合生理特性和分子生物学分析，研究了外源激素对大豆ATP酶活性的影响。在200 μ mAl时，其含量下降到对照水平。在含25、50或200 μmAl的根系培养基中，外加50 μmIAA，可降低根系Al浓度，促进Al诱导的柠檬酸分泌和质膜H+-ATPase活性。RT-PCR分析表明，外源IAA促进了柠檬酸分泌转运蛋白（GmMATE）基因的表达，但对质膜H+-ATPase基因的表达无明显影响。western blot结果表明，IAA增强了铝胁迫下大豆根系质膜H+-ATPase的磷酸化水平。结论生长素通过上调GmMATE和增加质膜H+-ATPase的磷酸化水平，增强铝胁迫下大豆根系柠檬酸盐分泌。
Background and AimsAluminium (Al) toxicity is a limiting factor for plant growth and crop production in acidic soils. Citrate exudation and activation of the plasma membrane H+-ATPase are involved in soybean responses to Al stress. Auxin has crucial functions in plant growth and stress responses. However, little is known about possible interactions between auxin and citrate exudation under Al stress. In this study, we elucidated the regulatory roles of IAA in Al-induced citrate exudation in soybean roots.MethodsWe measured IAA content, Al concentration, citrate exudation, plasma membrane H+-ATPase activity, expression of the relevant genes and phosphorylation of the plasma membrane H+-ATPase by integrating physiological characterization and molecular analysis using hydroponically grown soybean.Key Results The concentration of IAA was increased by 25 and 50 μmAl, but decreased to the control level at 200 μmAl. External addition of 50 μmIAA to the root medium containing 25, 50 or 200 μmAl decreased root Al concentration and stimulated Al-induced citrate exudation and the plasma membrane H+-ATPase activity. Reverse transcription–PCR analysis showed that exogenous IAA enhanced the expression of citrate exudation transporter (GmMATE) but not the plasma membrane H+-ATPase gene. The western blot results suggested that IAA enhanced phosphorylation of the plasma membrane H+-ATPase under Al stress.ConclusionsAuxin enhanced Al-induced citrate exudation through upregulation ofGmMATEand an increase in phosphorylation of the plasma membrane H+-ATPase in soybean roots.