DFR1-Mediated Inhibition of Proline Degradation Pathway Regulates Drought and Freezing Tolerance in Arabidopsis
DFR1-Mediated Inhibition of Proline Degradation Pathway Regulates Drought and Freezing Tolerance in Arabidopsis
复制标题
DFR1 介导的脯氨酸降解途径抑制调节拟南芥的干旱和冷冻耐受性
DOI：
10.1016/j.celrep.2018.04.011
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发表时间：
2018-06-26
期刊：
影响因子：
8.8
通讯作者：
Cao, Shuqing
中科院分区：
文献类型：
--
作者：
Ren, Yongbing;Miao, Min;Cao, Shuqing
脯氨酸的积累是植物科普干旱、冰冻等环境胁迫的重要适应机制之一。然而，在这些压力下脯氨酸稳态的分子机制在很大程度上是未知的。在这里，我们发现了一个线粒体！DFR 1蛋白参与拟南芥脯氨酸降解的抑制。DFR 1受干旱和低温胁迫强烈诱导。DFR 1敲低突变体表现出对干旱和冰冻胁迫的敏感性，而DFR 1过表达植株表现出增强的耐受性，这与脯氨酸水平呈正相关。DFR 1与脯氨酸降解酶PDH 1/2和P5 CDH相互作用并损害它们的活性。遗传分析表明，DFR 1作用于PDH 1/2和P5 CDH的上游，正调控脯氨酸的积累。我们的研究结果表明，在干旱和冰冻胁迫下，DFR 1与PDH 1/2和P5 CDH相互作用，废除其活动，以维持脯氨酸的稳态，从而赋予干旱和抗冻性的调节机制。
Proline accumulation is one of the most important adaptation mechanisms for plants to cope with environmental stresses, such as drought and freezing. However, the molecular mechanism of proline homeostasis under these stresses is largely unknown. Here, we identified a mitochondria! protein, DFR1, involved in the inhibition of proline degradation in Arabidopsis. DFR1 was strongly induced by drought and cold stresses. The dfr1 knockdown mutants showed hypersensitivity to drought and freezing stresses, whereas the DFR1 overexpression plants exhibited enhanced tolerance, which was positively correlated with proline levels. DFR1 interacts with proline degradation enzymes PDH1/2 and P5CDH and compromises their activities. Genetic analysis showed that DFR1 acts upstream of PDH1/2 and P5CDH to positively regulate proline accumulation. Our results demonstrate a regulatory mechanism by which, under drought and freezing stresses, DFR1 interacts with PDH1/2 and P5CDH to abrogate their activities to maintain proline homeostasis, thereby conferring drought and freezing tolerance.