Biochimie et Physiologie Moléculaire des Plantes, UMR5004, INRA/CNRS/Montpellier SupAgro/Université Montpellier, 34060 Montpellier, France.
Institut Jean-Pierre Bourgin, INRA/AgroParisTech/CNRS/Université Paris-Saclay, RD10, 78026 Versailles Cedex, France.
Cell. 2016 Sep 22;167(1):87-98.e14. doi: 10.1016/j.cell.2016.08.068. Epub 2016 Sep 15.
Aerobic organisms survive low oxygen (O2) through activation of diverse molecular, metabolic, and physiological responses. In most plants, root water permeability (in other words, hydraulic conductivity, Lpr) is downregulated under O2 deficiency. Here, we used a quantitative genetics approach in Arabidopsis to clone Hydraulic Conductivity of Root 1 (HCR1), a Raf-like MAPKKK that negatively controls Lpr. HCR1 accumulates and is functional under combined O2 limitation and potassium (K(+)) sufficiency. HCR1 regulates Lpr and hypoxia responsive genes, through the control of RAP2.12, a key transcriptional regulator of the core anaerobic response. A substantial variation of HCR1 in regulating Lpr is observed at the Arabidopsis species level. Thus, by combinatorially integrating two soil signals, K(+) and O2 availability, HCR1 modulates the resilience of plants to multiple flooding scenarios.
需氧生物通过激活各种分子、代谢和生理反应来在低氧（O2）环境中存活。在大多数植物中，根水渗透性（换句话说，水力传导率，Lpr）在缺氧下被下调。在这里，我们使用拟南芥的定量遗传学方法克隆了 Hydraulic Conductivity of Root 1（HCR1），这是一种 Raf 样 MAPKKK，可负向调控 Lpr。在 O2 限制和钾（K(+))充足的情况下，HCR1 积累并发挥功能。HCR1 通过控制 RAP2.12 来调节 Lpr 和缺氧响应基因，RAP2.12 是核心厌氧反应的关键转录调节因子。在拟南芥物种水平上，观察到 HCR1 在调节 Lpr 方面存在很大差异。因此，通过组合整合两种土壤信号（K(+)和 O2 可用性），HCR1 调节植物对多种淹没情况的恢复能力。
