Day Rebecca E, Kitchen Philip, Owen David S, Bland Charlotte, Marshall Lindsay, Conner Alex C, Bill Roslyn M, Conner Matthew T
Biomedical Research Centre, Sheffield Hallam University, Howard Street, Sheffield S1 1WB, UK.
Molecular Organisation and Assembly in Cells Doctoral Training Centre, University of Warwick, Coventry CV4 7AL, UK.
Biochim Biophys Acta. 2014 May;1840(5):1492-506. doi: 10.1016/j.bbagen.2013.09.033. Epub 2013 Sep 30.
Emerging evidence supports the view that (AQP) aquaporin water channels are regulators of transcellular water flow. Consistent with their expression in most tissues, AQPs are associated with diverse physiological and pathophysiological processes.
AQP knockout studies suggest that the regulatory role of AQPs, rather than their action as passive channels, is their critical function. Transport through all AQPs occurs by a common passive mechanism, but their regulation and cellular distribution varies significantly depending on cell and tissue type; the role of AQPs in cell volume regulation (CVR) is particularly notable. This review examines the regulatory role of AQPs in transcellular water flow, especially in CVR. We focus on key systems of the human body, encompassing processes as diverse as urine concentration in the kidney to clearance of brain oedema.
AQPs are crucial for the regulation of water homeostasis, providing selective pores for the rapid movement of water across diverse cell membranes and playing regulatory roles in CVR. Gating mechanisms have been proposed for human AQPs, but have only been reported for plant and microbial AQPs. Consequently, it is likely that the distribution and abundance of AQPs in a particular membrane is the determinant of membrane water permeability and a regulator of transcellular water flow.
Elucidating the mechanisms that regulate transcellular water flow will improve our understanding of the human body in health and disease. The central role of specific AQPs in regulating water homeostasis will provide routes to a range of novel therapies. This article is part of a Special Issue entitled Aquaporins.
新出现的证据支持这样一种观点，即水通道蛋白（AQP）是跨细胞水流的调节因子。与它们在大多数组织中的表达一致，水通道蛋白与多种生理和病理生理过程相关。
水通道蛋白基因敲除研究表明，水通道蛋白的关键功能是其调节作用，而非作为被动通道的作用。所有水通道蛋白的转运都通过一种常见的被动机制进行，但其调节和细胞分布因细胞和组织类型的不同而有显著差异；水通道蛋白在细胞体积调节（CVR）中的作用尤为显著。本综述探讨了水通道蛋白在跨细胞水流中的调节作用，特别是在细胞体积调节方面。我们关注人体的关键系统，包括从肾脏尿液浓缩到脑水肿清除等多种过程。
水通道蛋白对于水稳态的调节至关重要，为水在各种细胞膜上的快速移动提供选择性孔道，并在细胞体积调节中发挥调节作用。已有人提出人类水通道蛋白的门控机制，但仅在植物和微生物水通道蛋白中得到报道。因此，特定膜中水通道蛋白的分布和丰度可能是膜水通透性以及跨细胞水流调节的决定因素。
阐明调节跨细胞水流的机制将增进我们对人体健康和疾病的理解。特定水通道蛋白在调节水稳态中的核心作用将为一系列新疗法提供途径。本文是名为“水通道蛋白”的特刊的一部分。
