Two tonoplast MATE proteins function as turgor-regulating chloride channels in Arabidopsis
Two tonoplast MATE proteins function as turgor-regulating chloride channels in Arabidopsis
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两种液泡膜 MATE 蛋白在拟南芥中充当充压调节氯离子通道
DOI：
10.1073/pnas.1616203114
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发表时间：
2017-02
影响因子：
11.1
通讯作者：
Luan S
中科院分区：
文献类型：
--
作者：
Zhang Haiwen;Zhao Fu-Geng;Wang Yuan;Zhang Haiwen;Yu Yuexuan;Song Jiali;Li Legong;Zhang Haiwen;Tang Ren-Jie;Luan Sheng;Zhang Haiwen;Zhao FG;Li LG;Luan S
膨压是植物细胞生长的驱动力，而中央大液泡为膨压调节提供了主要空间。然而，许多控制水和溶质通量进出液泡的转运蛋白的分子身份和功能仍然未知。我们在这里报告，两个多药和有毒化合物挤出（MATE）型转运蛋白显示以前未被认识到的功能，在拟南芥中的膨压调节所必需的氯离子通道。MATE转运蛋白在细菌、真菌、植物和动物中高度保守，并被广泛接受为有机化合物的转运蛋白。这项研究显示，一些MATE转运蛋白作为氯离子通道，从而打破了这个大家族转运蛋白的功能定义的旧教条。植物细胞中的中央液泡占据了细胞体积的大部分，并且在膨压调节中起着关键作用。液泡膜（液泡膜）含有大量的转运蛋白，介导溶质和水的通量，从而调节细胞膨压响应发育和环境信号。我们报道了两个液泡膜脱钙外排载体（DTX）/多药和有毒化合物外排（MATE）转运蛋白，DTX 33和DTX 35，作为拟南芥膨压调节所必需的氯离子通道。烟草叶肉细胞中的每个转运蛋白的异位表达引起了一个大的电压依赖性内向氯电流跨液泡膜，表明DTX 33和DTX 35各自构成一个功能通道。这两种通道在拟南芥组织中高度表达，包括根毛和保卫细胞，它们在根毛伸长和气孔运动期间经历快速的膨压变化。这两个基因的破坏，无论是在单或双突变体，导致较短的根毛和较小的气孔孔径，与双突变体表现出更严重的缺陷，这表明这两个通道的功能相加，以促进阴离子流入液泡在细胞扩张。此外，dtx 35单突变体表现出较低的育性，由于在花粉管生长的缺陷。事实上，膜片钳记录的孤立的液泡表明，内向氯离子通道的活动，整个液泡膜受损的双突变体。由于MATE蛋白是广泛已知的有机化合物转运蛋白，发现MATE成员作为氯离子通道扩展了这个转运蛋白大家族的功能定义。
Significance Turgor pressure is the driving force for cell growth in plants, and the large central vacuole provides the major space for turgor regulation. However, the molecular identity and function of many transporters that control water and solute fluxes in and out of vacuoles remain unknown. We report here that two Multidrug and Toxic Compound Extrusion (MATE)-type transporters show previously unrecognized function as chloride channels essential for turgor regulation in Arabidopsis. The MATE transporters are highly conserved from bacteria, fungi, plants, to animals, and widely accepted as transporters of organic compounds. This study, showing some MATE transporters as chloride channels, thus breaks the old dogma on the functional definition of this large family of transporters. The central vacuole in a plant cell occupies the majority of the cellular volume and plays a key role in turgor regulation. The vacuolar membrane (tonoplast) contains a large number of transporters that mediate fluxes of solutes and water, thereby adjusting cell turgor in response to developmental and environmental signals. We report that two tonoplast Detoxification efflux carrier (DTX)/Multidrug and Toxic Compound Extrusion (MATE) transporters, DTX33 and DTX35, function as chloride channels essential for turgor regulation in Arabidopsis. Ectopic expression of each transporter in Nicotiana benthamiana mesophyll cells elicited a large voltage-dependent inward chloride current across the tonoplast, showing that DTX33 and DTX35 each constitute a functional channel. Both channels are highly expressed in Arabidopsis tissues, including root hairs and guard cells that experience rapid turgor changes during root-hair elongation and stomatal movements. Disruption of these two genes, either in single or double mutants, resulted in shorter root hairs and smaller stomatal aperture, with double mutants showing more severe defects, suggesting that these two channels function additively to facilitate anion influx into the vacuole during cell expansion. In addition, dtx35 single mutant showed lower fertility as a result of a defect in pollen-tube growth. Indeed, patch-clamp recording of isolated vacuoles indicated that the inward chloride channel activity across the tonoplast was impaired in the double mutant. Because MATE proteins are widely known transporters of organic compounds, finding MATE members as chloride channels expands the functional definition of this large family of transporters.
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DOI：
10.1073/pnas.0912021106
发表时间：
2009-12-15
影响因子：
11.1
作者：
Geiger, Dietmar;Scherzer, Soenke;Hedrich, Rainer
通讯作者：
Hedrich, Rainer
Atalmt9是拟南芥中气孔开口所需的苹果酸液泡氯化物通道。
影响因子：
16.6
作者：
通讯作者：
--
影响因子：
7.2
作者：
Kovermann, Peter;Meyer, Stefan;Martinoia, Enrico
通讯作者：
Martinoia, Enrico
影响因子：
7.4
作者：
Ligaba, Ayalew;Katsuhara, Maki;Matsumoto, Hideaki
通讯作者：
Matsumoto, Hideaki
影响因子：
3.5
作者：
G. Zifarelli;Michael Pusch
通讯作者：
G. Zifarelli;Michael Pusch