Regulation of MIR165/166 by class II and class III homeodomain leucine zipper proteins establishes leaf polarity
Regulation of MIR165/166 by class II and class III homeodomain leucine zipper proteins establishes leaf polarity
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DOI：
10.1073/pnas.1516110113
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发表时间：
2016-10-18
影响因子：
11.1
通讯作者：
Heisler, Marcus G.
中科院分区：
文献类型：
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作者：
Merelo, Paz;Ram, Hathi;Heisler, Marcus G.
植物叶子的一个明显特征是它们扁平的形状。这种形状取决于指定近轴（顶部）和远轴（底部）组织身份的基因之间的拮抗作用;然而，这种拮抗作用的分子本质仍然知之甚少。III类同源结构域亮氨酸拉链（HD-ZIP）转录因子是调节近轴-远轴模式的关键介质。它们的表达在发育早期受到背面表达的microRNA（MIR）165/166的正面限制，但限制MIR 165/166表达到背面叶组织的机制仍然未知。在这里，我们表明，III类和II类HD-ZIP蛋白共同作用，通过其启动子中的保守顺式元件抑制MIR 165/166。因此，植物的器官形态和组织模式依赖于一个涉及一组miRNA及其靶标的双向抑制回路。
A defining feature of plant leaves is their flattened shape. This shape depends on an antagonism between the genes that specify adaxial (top) and abaxial (bottom) tissue identity; however, the molecular nature of this antagonism remains poorly understood. Class III homeodomain leucine zipper (HD-ZIP) transcription factors are key mediators in the regulation of adaxial-abaxial patterning. Their expression is restricted adaxially during early development by the abaxially expressed microRNA (MIR) 165/166, yet the mechanism that restricts MIR165/166 expression to abaxial leaf tissues remains unknown. Here, we show that class III and class II HD-ZIP proteins act together to repress MIR165/166 via a conserved cis-element in their promoters. Organ morphology and tissue patterning in plants, therefore, depend on a bidirectional repressive circuit involving a set of miRNAs and its targets.