Regulation of auxin response by miR393-targeted transport inhibitor response protein 1 is involved in normal development in Arabidopsis
Regulation of auxin response by miR393-targeted transport inhibitor response protein 1 is involved in normal development in Arabidopsis
复制标题
miR393靶向转运抑制剂反应蛋白1对生长素反应的调节参与拟南芥的正常发育
DOI：
10.1007/s11103-011-9838-1
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发表时间：
2011-12-01
影响因子：
5.1
通讯作者：
Zhu, Mu-Yuan
中科院分区：
文献类型：
--
作者：
Chen, Zhe-Hao;Bao, Mao-Lin;Zhu, Mu-Yuan
miR 393在拟南芥中由MIR 393 a和MIR 393 b编码，转录后调节F-box生长素受体TIR 1（转运抑制剂反应蛋白1）、AFB 1（生长素信号F-box蛋白1）、AFB 2和AFB 3的mRNA。然而，miR 393-TIR 1/AFB模块在生长素应答和植物发育中的生物学功能尚未完全了解。在本文的研究中，我们证明了miR 393响应于外源IAA处理而积累，并且其诱导是由于MIR 393 b转录增强而不是MIR 393 a。miR 393抗性形式的TIR 1（mTIR 1）的过表达增强了生长素敏感性，并导致对植物发育的多效性效应，包括抑制主根生长、侧根过量产生、改变叶表型和延迟开花。此外，在35 S：mTIR 1植株中miR 393的表达量增加，表明TIR 1通过反馈环促进miR 393的表达。miR 393与其靶标之间的相互作用表明对miR 393-TIR 1模块的作用进行了微调，这是植物发育中生长素反应所必需的。
miR393, which is encoded by MIR393a and MIR393b in Arabidopsis, post-transcriptionally regulates mRNAs for the F-box auxin receptors TIR1 (Transport Inhibitor Response Protein 1), AFB1 (Auxin Signaling F-box Protein 1), AFB2 and AFB3. However, biological functions of the miR393-TIR1/AFBs module in auxin response and plant development is not fully understood. In the study herein, we demonstrate that miR393 accumulated in response to exogenous IAA treatment, and its induction was due to enhanced MIR393b transcription but not MIR393a. Overexpression of a miR393-resistant form of TIR1 (mTIR1) enhanced auxin sensitivity and led to pleiotropic effects on plant development including inhibition of primary root growth, overproduction of lateral roots, altered leave phenotype and delayed flowering. Furthermore, miR393 level was increased in 35S:mTIR1 plant, suggesting that TIR1 promoted the expression of miR393 by a feedback loop. The interaction between miR393 and its target indicates a fine adjustment to the roles of the miR393-TIR1 module, which is required for auxin responses in plant development.