Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
Induction of root Fe(lll) reductase activity and proton extrusion by iron deficiency is mediated by auxin-based systemic signalling in Malus xiaojinensis
复制标题
小金海棠中基于生长素的系统信号介导缺铁诱导根部 Fe(III) 还原酶活性和质子排出
DOI：
10.1093/jxb/err314
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发表时间：
2011-11
影响因子：
6.9
通讯作者：
Han, Zhen Hai
中科院分区：
文献类型：
--
作者：
Wu, Ting;Zhang, Heng-Tao;Wang, Yi;Jia, Wen-Suo;Xu, Xue-Feng;Zhang, Xin-Zhong;Han, Zhen Hai
铁是参与呼吸和光合作用的许多金属酶的关键辅助因子，但由于土壤中可溶性铁供应有限，植物经常遭受缺铁的困扰。缺铁在多种植物中引起一系列适应性反应，但其触发机制在很大程度上仍不清楚。利用pH成像和激素定位技术，研究人员发现，在铁效率高的木本植物小金苹果（Malus xiaojinensis）中，根系铁（III）还原酶活性和铁缺乏时的质子挤压受到系统性生长素信号的上调。劈裂根实验表明，部分根系缺铁导致铁（III）还原酶活性和铁供应部分的质子挤压显著增加，表明缺铁反应是由系统性信号传导介导的。小金木与不具有相应应答能力的海棠（Malus baccata）的反向嫁接实验表明，系统信号的启动可能是由根而不是茎决定的。铁缺乏导致茎尖IAA含量大幅增加，向茎尖提供外源IAA类似物（NAA）可以模拟铁缺乏，从而引发相应的反应。相反，阻止IAA从茎部到根的运输会阻断缺铁反应。这些结果有力地表明，铁缺乏诱导的生理反应是由全身生长素信号介导的。
Iron is a critical cofactor for a number of metalloenzymes involved in respiration and photosynthesis, but plants often suffer from iron deficiency due to limited supplies of soluble iron in the soil. Iron deficiency induces a series of adaptive responses in various plant species, but the mechanisms by which they are triggered remain largely unknown. Using pH imaging and hormone localization techniques, it has been demonstrated here that root Fe(III) reductase activity and proton extrusion upon iron deficiency are up-regulated by systemic auxin signalling in a Fe-efficient woody plant, Malus xiaojinensis. Split-root experiments demonstrated that Fe-deprivation in a portion of the root system induced a dramatic increase in Fe(III) reductase activity and proton extrusion in the Fe-supplied portion, suggesting that the iron deficiency responses were mediated by a systemic signalling. Reciprocal grafting experiments of M. xiaojinensis with Malus baccata, a plant with no capability to produce the corresponding responses, indicate that the initiation of the systemic signalling is likely to be determined by roots rather than shoots. Iron deficiency induced a substantial increase in the IAA content in the shoot apex and supplying exogenous IAA analogues (NAA) to the shoot apex could mimic the iron deficiency to trigger the corresponding responses. Conversely, preventing IAA transport from shoot to roots blocked the iron deficiency responses. These results strongly indicate that the iron deficiency-induced physiological responses are mediated by systemic auxin signalling.
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DOI：
10.1104/pp.106.2.815
发表时间：
1994-10
期刊：
--
影响因子：
--
作者：
Fuqiang Chen;P. Hayes;D. Mulrooney;A. Pan
通讯作者：
Fuqiang Chen;P. Hayes;D. Mulrooney;A. Pan
影响因子：
2.1
作者：
LANDSBERG, EC
通讯作者：
LANDSBERG, EC
影响因子：
2.1
作者：
Han, ZH;Shen, T;Baligar, VC
通讯作者：
Baligar, VC
DOI：
10.1104/pp.105.4.1133
发表时间：
1994-08
期刊：
--
影响因子：
--
作者：
F. Romera;E. Alcántara
通讯作者：
F. Romera;E. Alcántara
影响因子：
7.4
作者：
Wolfgang Schmidt;Julia Tittel;Adam Schikora
通讯作者：
Wolfgang Schmidt;Julia Tittel;Adam Schikora