Regulation of the KNOX-GA Gene Module Induces Heterophyllic Alteration in North American Lake Cress
Regulation of the KNOX-GA Gene Module Induces Heterophyllic Alteration in North American Lake Cress
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DOI：
10.1105/tpc.114.130229
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发表时间：
2014-12-01
期刊：
影响因子：
11.6
通讯作者：
Kimura, Seisuke
中科院分区：
文献类型：
--
作者：
Nakayama, Hokuto;Nakayama, Naomi;Kimura, Seisuke
植物会因周围环境的变化而改变叶的形状，这种现象称为异叶性。虽然在植物物种中可以看到异形叶，但所涉及的调节机制在很大程度上是未知的。在这里，我们调查的机制，在Rorippa aquatica（菊科），也被称为北美湖水芹异叶。R.水生植物在淹没条件下形成羽状多裂叶，而在陆地条件下形成具有锯齿状边缘的单叶。我们发现，KNOX 1同源基因的表达水平随着周围环境的变化而变化。例如，在一个实施例中，环境温度的变化;低于或高于水），并且被认为受KNOX 1基因调控的赤霉素（GA）的积累也在叶原基中发生变化。我们进一步证明了外源GA影响该物种的叶形的复杂性。此外，RNA-seq揭示了光强度与叶形之间的关系。这些结果表明，通过KNOX 1基因调节GA水平参与了R.水生植物种间叶型形态多样性的机制也可能决定了种内叶型对环境变化的响应。
Plants show leaf form alteration in response to changes in the surrounding environment, and this phenomenon is called heterophylly. Although heterophylly is seen across plant species, the regulatory mechanisms involved are largely unknown. Here, we investigated the mechanism underlying heterophylly in Rorippa aquatica (Brassicaceae), also known as North American lake cress. R. aquatica develops pinnately dissected leaves in submerged conditions, whereas it forms simple leaves with serrated margins in terrestrial conditions. We found that the expression levels of KNOTTED1-LIKE HOMEOBOX (KNOX1) orthologs changed in response to changes in the surrounding environment (e. g., change of ambient temperature; below or above water) and that the accumulation of gibberellin (GA), which is thought to be regulated by KNOX1 genes, also changed in the leaf primordia. We further demonstrated that exogenous GA affects the complexity of leaf form in this species. Moreover, RNA-seq revealed a relationship between light intensity and leaf form. These results suggest that regulation of GA level via KNOX1 genes is involved in regulating heterophylly in R. aquatica. The mechanism responsible for morphological diversification of leaf form among species may also govern the variation of leaf form within a species in response to environmental changes.