Deciphering the role of water channel aquaporin-4 in muscle and brain

水通道称为水通道蛋白(AQP)，是一种膜蛋白，负责将水分子输送进和流出细胞。AQP4选择性地表达在快速抽动(II型)纤维的肌膜上，是人脑中含量最丰富的蛋白质之一。然而，它在肌肉和大脑中的作用仍然难以捉摸。我们以前发现AQP4定位于肌肉和脑的细胞膜上(Yokota等人)。2000)。最近，我们发现，在渗透性休克或跑步机运动后，α-合成素缺乏的肌肉表现出肌肉容量调节和肌力恢复的受损(Yokota等人。2014年，Nichols等人。2015年)。我们推测：1)AQP4在运动中和运动后肌肉疲劳的恢复中起重要作用；2)AQP4参与运动中和运动后脑脊液流量的增加。这项研究的目的是通过分析突变小鼠模型来破译AQP4的新角色。

Water channels called aquaporins (AQPs) are membrane proteins that conduct water molecules in and out of the cell. AQP4 is selectively expressed at the muscle membrane of fast twitch (type II) fibres, and one of the most abundant proteins in human brain. However, its roles in muscle and brain have remained elusive. We previously identified that AQP4 is localized by alpha-syntrophin at the cell membrane in muscle and brain (Yokota et al. 2000). More recently, we have shown that alpha-syntrophin deficient muscles exhibit impaired muscle volume regulation and muscle force recovery after osmotic shocks or treadmill exercise (Yokota et al. 2014, Nichols et al. 2015). We hypothesize that 1) AQP4 plays important roles in recovery from muscle fatigue during and after exercise, and 2) AQP4 is involved in increased cerebrospinal fluid (CSF) flow during and after exercise. The goal of this study is to decipher novel roles of AQP4 by analyzing mutant mouse models.