AUX1-mediated root hair auxin influx governs SCF(TIR1/AFB)-type Ca(2+) signaling.
AUX1-mediated root hair auxin influx governs SCF(TIR1/AFB)-type Ca(2+) signaling.
复制标题
DOI：
10.1038/s41467-018-03582-5
复制
发表时间：
2018-03-21
影响因子：
16.6
通讯作者：
Hedrich R
中科院分区：
文献类型：
--
作者：
Dindas J;Scherzer S;Roelfsema MRG;von Meyer K;Müller HM;Al-Rasheid KAS;Palme K;Dietrich P;Becker D;Bennett MJ;Hedrich R
生长素是植物生长发育的关键调节因子，但激素运输与根系反应之间的因果关系尚未得到解决。在这里，我们描述生长素的吸收，连同信号的早期步骤，在拟南芥根毛。使用细胞内微电极，我们显示膜去极化，响应于IAA的浓度和pH值依赖性的方式。这种去极化在aux 1突变体中强烈受损，表明AUX 1是根毛中生长素吸收的主要转运蛋白。局部细胞内生长素的应用触发Ca 2+信号，作为长距离波在根细胞之间传播，并调节它们的生长素反应。AUX 1介导的IAA转运，以及IAA触发的钙信号，被SCFTIR 1/AFB抑制剂生长素处理阻断。此外，它们在tir 1afb 2afb 3和cngc 14突变体中强烈减少。我们的研究表明，AUX 1转运蛋白，SCFTIR 1/AFB受体和CNGC 14 Ca 2+通道，介导快速生长素信号在根中。生长素调节植物生长和发育的多个方面。在这里，Dindas等人表明，在根毛细胞中，AUX 1生长素流入载体介导质子驱动的生长素输入，该输入被生长素受体感知并与可能调节根中的适应性反应的Ca 2+波耦合。
Auxin is a key regulator of plant growth and development, but the causal relationship between hormone transport and root responses remains unresolved. Here we describe auxin uptake, together with early steps in signaling, in Arabidopsis root hairs. Using intracellular microelectrodes we show membrane depolarization, in response to IAA in a concentration- and pH-dependent manner. This depolarization is strongly impaired in aux1 mutants, indicating that AUX1 is the major transporter for auxin uptake in root hairs. Local intracellular auxin application triggers Ca2+ signals that propagate as long-distance waves between root cells and modulate their auxin responses. AUX1-mediated IAA transport, as well as IAA- triggered calcium signals, are blocked by treatment with the SCFTIR1/AFB - inhibitor auxinole. Further, they are strongly reduced in the tir1afb2afb3 and the cngc14 mutant. Our study reveals that the AUX1 transporter, the SCFTIR1/AFB receptor and the CNGC14 Ca2+ channel, mediate fast auxin signaling in roots. Auxin regulates multiple aspects of plant growth and development. Here Dindas et al. show that in root-hair cells, the AUX1 auxin influx carrier mediates proton-driven auxin import that is perceived by auxin receptors and coupled to Ca2+ waves that may modulate adaptive responses in the root.