Phenotypic Plasticity of Adventitious Rooting in Arabidopsis Is Controlled by Complex Regulation of AUXIN RESPONSE FACTOR Transcripts and MicroRNA Abundance
Phenotypic Plasticity of Adventitious Rooting in Arabidopsis Is Controlled by Complex Regulation of AUXIN RESPONSE FACTOR Transcripts and MicroRNA Abundance
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DOI：
10.1105/tpc.108.064758
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发表时间：
2009-10-01
期刊：
影响因子：
11.6
通讯作者：
Bellini, Catherine
中科院分区：
文献类型：
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作者：
Gutierrez, Laurent;Bussell, John D.;Bellini, Catherine
茎生根或不定根的发育对于优良基因型的大量繁殖是必不可少的。它是一个复杂的遗传性状，由于多种内源和环境调节因素，具有高度的表型可塑性。我们在这里证明，一个微妙的平衡激活和抑制生长素反应因子（ARF）转录控制不定根的启动。此外，microRNA活性似乎是微调这一过程所必需的。因此，ARF17，miR160的目标，是一个负调节，和ARF6和ARF8，miR167的目标，是不定生根的正调节。这三种ARF显示重叠的表达结构域，在遗传上相互作用，并通过调节miR160和miR167的可用性在转录和转录后水平上调节彼此的表达。这种复杂的调控网络包括通过直接和非直接靶转录因子对microRNA稳态的意想不到的反馈调节。这些结果提供了microRNA控制表型变异的证据，并且在理解调节不定根的分子机制方面向前迈出了重要的一步。
The development of shoot-borne roots, or adventitious roots, is indispensable for mass propagation of elite genotypes. It is a complex genetic trait with a high phenotypic plasticity due to multiple endogenous and environmental regulatory factors. We demonstrate here that a subtle balance of activator and repressor AUXIN RESPONSE FACTOR (ARF) transcripts controls adventitious root initiation. Moreover, microRNA activity appears to be required for fine-tuning of this process. Thus, ARF17, a target of miR160, is a negative regulator, and ARF6 and ARF8, targets of miR167, are positive regulators of adventitious rooting. The three ARFs display overlapping expression domains, interact genetically, and regulate each other's expression at both transcriptional and posttranscriptional levels by modulating miR160 and miR167 availability. This complex regulatory network includes an unexpected feedback regulation of microRNA homeostasis by direct and nondirect target transcription factors. These results provide evidence of microRNA control of phenotypic variability and are a significant step forward in understanding the molecular mechanisms regulating adventitious rooting.