OsIAA6, a member of the rice Aux/IAA gene family, is involved in drought tolerance and tiller outgrowth
OsIAA6, a member of the rice Aux/IAA gene family, is involved in drought tolerance and tiller outgrowth
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DOI：
10.1016/j.plantsci.2015.04.018
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发表时间：
2015-07-01
期刊：
影响因子：
5.2
通讯作者：
Kim, Ju-Kon
中科院分区：
文献类型：
--
作者：
Jung, Harin;Lee, Dong-Keun;Kim, Ju-Kon
生长素信号传导是许多植物生长过程和胁迫反应的基本组成部分，通过 Aux/IAA 蛋白降解和通过生长素响应因子 (ARF) 传输信号来发挥作用。水稻 (Oryza sativa) 中总共鉴定了 31 个 Aux/IAA 基因，其中一些是由干旱胁迫诱导的。然而，Aux/IAA 表达与干旱反应之间的机制联系尚不清楚。在这项研究中，我们发现水稻 Aux/IAA 基因 OsIAA6 受到干旱胁迫的高度诱导，并且其在转基因水稻中的过度表达可能通过生长素生物合成基因的调节提高了耐旱性。我们观察到 OsIAA6 在基茎的腋生分生组织中特异性表达，基茎是产生分蘖的组织。 OsIAA6 的敲除突变体表现出异常的分蘖生长，这显然是由于生长素转运蛋白 OsPIN1 和水稻分蘖抑制剂 OsTB1 的调节所致。我们的结果证实 OsIAA6 基因参与干旱胁迫反应和分蘖生长的控制。 (C) 2015 Elsevier Ireland Ltd. 保留所有权利。
Auxin signaling is a fundamental part of many plant growth processes and stress responses and operates through Aux/IAA protein degradation and the transmission of the signal via auxin response factors (ARFs). A total of 31 Aux/IAA genes have been identified in rice (Oryza sativa), some of which are induced by drought stress. However, the mechanistic link between Aux/IAA expression and drought responses is not well understood. In this study we found that the rice Aux/IAA gene OsIAA6 is highly induced by drought stress and that its overexpression in transgenic rice improved drought tolerance, likely via the regulation of auxin biosynthesis genes. We observed that OsIAA6 was specifically expressed in the axillary meristem of the basal stem, which is the tissue that gives rise to tillers. A knock-down mutant of OsIAA6 showed abnormal tiller outgrowth, apparently due to the regulation of the auxin transporter OsPIN1 and the rice tillering inhibitor OsTB1. Our results confirm that the OsIAA6 gene is involved in drought stress responses and the control of tiller outgrowth. (C) 2015 Elsevier Ireland Ltd. All rights reserved.