Auxin promotes Arabidopsis root growth by modulating gibberellin response
Auxin promotes Arabidopsis root growth by modulating gibberellin response
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DOI：
10.1038/nature01387
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发表时间：
2003-02-13
期刊：
影响因子：
64.8
通讯作者：
Harberd, NP
中科院分区：
文献类型：
--
作者：
Fu, XD;Harberd, NP
植物器官的生长受到植物激素生长素流的影响，生长素流从茎尖流向根尖（1）。然而，到目前为止，还不知道生长素如何调节细胞增殖和扩大，器官生长的特点。在这里，我们表明，生长素控制根的生长，通过调节细胞的反应，植物激素赤霉素（GA）。GA通过对抗核DELLA蛋白生长阻遏物的作用来促进植物的生长（2-8），其中之一是拟南芥RGA（gal-3的阻遏物）（9，10）。GA通过使几种DELLA蛋白不稳定来对抗它们的作用，降低可检测DELLA蛋白的浓度及其生长抑制作用（9-14）。我们还表明，生长素是必要的GA介导的控制根的生长，生长素运输或信号衰减延迟GA诱导的RGA从根细胞核消失。我们的观察表明，茎尖施加长距离控制植物器官的生长，通过生长素对GA介导的DELLA蛋白不稳定的影响。
The growth of plant organs is influenced by a stream of the phytohormone auxin that flows from the shoot apex to the tip of the root(1). However, until now it has not been known how auxin regulates the cell proliferation and enlargement that characterizes organ growth. Here we show that auxin controls the growth of roots by modulating cellular responses to the phytohormone gibberellin (GA). GA promotes the growth of plants by opposing the effects of nuclear DELLA protein growth repressors(2-8), one of which is Arabidopsis RGA (for repressor of gal-3)(9,10). GA opposes the action of several DELLA proteins by destabilizing them, reducing both the concentration of detectable DELLA proteins and their growth-restraining effects(9-14). We also show that auxin is necessary for GA-mediated control of root growth, and that attenuation of auxin transport or signalling delays the GA-induced disappearance of RGA from root cell nuclei. Our observations indicate that the shoot apex exerts long-distance control on the growth of plant organs through the effect of auxin on GA-mediated DELLA protein destabilization.