Chloride channels (CLCs), a member of anion transporting proteins, are present ubiquitously in all life forms. Diverging from its name, the CLC family includes both channel and exchanger (proton-coupled) proteins; nevertheless, they share conserved structural organization. They are engaged in diverse indispensable functions such as acid and fluoride tolerance in prokaryotes to muscle stabilization, transepithelial transport, and neuronal development in mammals. Mutations in genes encoding CLCs lead to several physiological disorders in different organisms, including severe diseases in humans. Even in plants, loss of CLC protein function severely impairs various cellular processes critical for normal growth and development. These proteins sequester Cl- into the vacuole, thus making them an attractive target for improving salinity tolerance in plants caused by high abundance of salts, primarily NaCl. Besides, some CLCs are involved in NO3 - transport and storage function in plants, thus influencing their nitrogen use efficiency. However, despite their high significance, not many studies have been carried out in plants. Here, we have attempted to concisely highlight the basic structure of CLC proteins and critical residues essential for their function and classification. We also present the diverse functions of CLCs in plants from their first cloning back in 1996 to the knowledge acquired as of now. We stress the need for carrying out more in-depth studies on CLCs in plants, for they may have future applications towards crop improvement. This article is protected by copyright. All rights reserved.

中文翻译：

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氯离子通道：默默地为植物服务

氯离子通道 (CLC) 是阴离子转运蛋白的一个成员，在所有生命形式中都普遍存在。与其名称不同，CLC 家族包括通道和交换器（质子耦合）蛋白；然而，它们共享保守的结构组织。它们参与多种不可或缺的功能，例如原核生物的酸和氟耐受性，以稳定肌肉、跨上皮运输和哺乳动物的神经元发育。编码 CLC 的基因突变会导致不同生物体的多种生理疾病，包括人类的严重疾病。即使在植物中，CLC 蛋白功能的丧失也会严重损害对正常生长和发育至关重要的各种细胞过程。这些蛋白质将氯离子隔离在液泡中，从而使它们成为提高由高丰度盐（主要是 NaCl）引起的植物耐盐性的有吸引力的目标。此外，一些CLCs参与植物中NO3的运输和储存功能，从而影响其氮的利用效率。然而，尽管它们具有很高的意义，但在植物中进行的研究并不多。在这里，我们试图简明地强调 CLC 蛋白的基本结构和对其功能和分类至关重要的关键残基。我们还介绍了从 1996 年首次克隆到目前获得的知识，CLC 在植物中的多种功能。我们强调需要对植物中的 CLC 进行更深入的研究，因为它们可能在未来用于作物改良。本文受版权保护。版权所有。