Modulation of Guard Cell Turgor and Drought Tolerance by a Peroxisomal Acetate-Malate Shunt
Modulation of Guard Cell Turgor and Drought Tolerance by a Peroxisomal Acetate-Malate Shunt
复制标题
通过过氧化物酶体乙酸-苹果酸分流调节保卫细胞的膨压和耐旱性。
DOI：
10.1016/j.molp.2018.07.008
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发表时间：
2018-10-08
期刊：
影响因子：
27.5
通讯作者：
Song, Chun-Peng
中科院分区：
文献类型：
--
作者：
Dong, Huan;Bai, Ling;Song, Chun-Peng
在植物中，气孔运动受到细胞膨压变化的严格控制。糖酵解和三羧酸循环产生的碳水化合物在调节膨压中起重要作用。在这里，我们描述了一个假单胞菌，bzu 1，在屏幕上分离的叶片温度升高，在干旱胁迫下，表现出更小的气孔和更高的抗旱性比野生型植物。BZU 1编码一种已知的乙酰辅酶A合成酶，ACN 1，它在过氧化物酶体中将乙酸转化为苹果酸的代谢途径的第一步中起作用。我们发现，BZU 1/ACN 1介导的乙酸到苹果酸的转换提供了一个分流，发挥了重要作用，在气孔膨压的调节。我们发现，在bzu 1突变体的气孔较小的苹果酸，这作为一种抑制剂和/或信号分子在保卫细胞内的膨压控制的积累减少的结果，这些结果提供了新的遗传证据苹果酸调节气孔运动。总的来说，我们的研究结果表明，过氧化物酶体BZU 1/ACN 1介导的乙酸-苹果酸分流调节耐旱性通过控制在拟南芥保卫细胞的膨压。
In plants, stomatal movements are tightly controlled by changes in cellular turgor pressure. Carbohydrates produced by glycolysis and the tricarboxylic acid cycle play an important role in regulating turgor pressure. Here, we describe an Arabidopsismutant, bzu1, isolated in a screen for elevated leaf temperature in response to drought stress, which displays smaller stomatal pores and higher drought resistance than wild-type plants. BZU1 encodes a known acetyl-coenzyme A synthetase, ACN1, which acts in the first step of a metabolic pathway converting acetate to malate in peroxisomes. We showed that BZU1/ACN1-mediated acetate-to-malate conversion provides a shunt that plays an important role in osmoregulation of stomatal turgor. We found that the smaller stomatal pores in the bzu1 mutant are a consequence of reduced accumulation of malate, which acts as an osmoticum and/or a signaling molecule in the control of turgor pressure within guard cells, and these results provided new genetic evidence for malate-regulated stomatal movement. Collectively, our results indicate that a peroxisomal BZU1/ACN1-mediated acetate-malate shunt regulates drought resistance by controlling the turgor pressure of guard cells in Arabidopsis.