The root cap determines ethylene-dependent growth and development in maize roots
The root cap determines ethylene-dependent growth and development in maize roots
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DOI：
10.1093/mp/ssm027
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发表时间：
2008-03-01
期刊：
影响因子：
27.5
通讯作者：
Edelmann, Hans G.
中科院分区：
文献类型：
--
作者：
Hahn, Achim;Zimmermann, Roman;Edelmann, Hans G.
除了对根尖的机械损伤提供保护外，根帽还参与感知和处理各种外部和内部刺激，从而改变生长和发育。这些刺激的转导包括激素信号通路，如生长素、乙烯和细胞分裂素。在这里，我们表明根冠在乙烯诱导的玉米伸长生长和根毛形成的调节中是必不可少的。外源应用的乙烯不再能够抑制伸长生长，当根冠在激素治疗之前被外科手术移除时。帽子的重建与根对乙烯再次反应的发育能力呈正相关。相反，去除根冠本身并不影响生长素和细胞分裂素控制的生长抑制。此外，我们的半定量RT-PCR结果支持了早先的发现，即玉米根冠是一个高基因表达活性的位置，可以感知和响应激素，如乙烯。根据这些数据，我们提出了根冠的一个新功能，即在根的远端区域建立对乙烯反应的能力。
Besides providing protection against mechanical damage to the root tip, the root cap is involved in the perception and processing of diverse external and internal stimuli resulting in altered growth and development. The transduction of these stimuli includes hormonal signaling pathways such as those of auxin, ethylene and cytokinin. Here, we show that the root cap is essential for the ethylene-induced regulation of elongation growth and root hair formation in maize. Exogenously applied ethylene is no longer able to inhibit elongation growth when the root cap has been surgically removed prior to hormone treatment. Reconstitution of the cap positively correlates with the developing capacity of the roots to respond to ethylene again. In contrast, the removal of the root cap does not per se affect growth inhibition controlled by auxin and cytokinin. Furthermore, our semi-quantitative RT-PCR results support earlier findings that the maize root cap is a site of high gene expression activity with respect to sensing and responding to hormones such as ethylene. From these data, we propose a novel function of the root cap which is the establishment of competence to respond to ethylene in the distal zones of the root.