Igual Gil Carla, Jarius Mirko, von Kries Jens P, Rohlfing Anne-Katrin
Zoophysiology, Institute for Biochemistry and Biology, University PotsdamPotsdam, Germany.
Leibniz-Institut für Molekulare Pharmakologie (FMP)Berlin, Germany.
Front Physiol. 2017 Jun 9;8:380. doi: 10.3389/fphys.2017.00380. eCollection 2017.
Aquaporins occupy an essential role in sustaining the salt/water balance in various cells types and tissues. Here, we present new insights into expression and regulation in . We show, that upon exposure to osmotic stress, exhibits a distinct expression pattern within the excretory cell compared to other aquaporins expressed. This expression is correlated to the osmolarity of the surrounding medium and can be activated physiologically by osmotic stress or genetically in mutants with constitutively active osmotic stress response. In addition, we found expression to be constitutively active in the TRPV channel mutant . In a genome-wide RNAi screen we identified additional regulators of . Many of these regulators are connected to chemosensation by the amphid neurons, e.g., and , and act as suppressors of expression. We postulate from our results, that plays an important role in sustaining the salt/water balance during a secondary response to hyper-osmotic stress. Upon its activation promotes vesicle docking to the lumen of the excretory cell and thereby enhances the ability to secrete water and transport osmotic active substances or waste products caused by protein damage. In summary, expression and function is tightly regulated by a network consisting of the osmotic stress response, neuronal chemosensation as well as the response to protein damage. These new insights in maintaining the salt/water balance in will help to reveal the complex homeostasis network preserved throughout species.
水通道蛋白在维持各种细胞类型和组织中的盐/水平衡方面发挥着重要作用。在此，我们展示了关于[具体对象]中表达和调控的新见解。我们发现，与其他已表达的水通道蛋白相比，在暴露于渗透压胁迫时，[具体对象]在排泄细胞内呈现出独特的表达模式。这种表达与周围介质的渗透压相关，并且可以通过渗透压胁迫在生理上激活，或者在具有组成型活性渗透压应激反应的突变体中通过基因方式激活。此外，我们发现[具体对象]在TRPV通道突变体[具体名称]中组成型激活表达。在全基因组RNAi筛选中，我们鉴定出了[具体对象]的其他调节因子。这些调节因子中的许多与两性神经元的化学感受相关，例如[具体因子1]和[具体因子2]，并作为[具体对象]表达的抑制因子。根据我们的结果推测，[具体对象]在高渗胁迫的二次反应过程中维持盐/水平衡方面发挥着重要作用。其激活后促进囊泡对接至排泄细胞的管腔，从而增强分泌水以及运输由蛋白质损伤导致的渗透活性物质或废物的能力。总之，[具体对象]的表达和功能受到一个由渗透压应激反应、神经元化学感受以及对蛋白质损伤的反应组成的网络的严格调控。这些关于维持[具体对象]盐/水平衡的新见解将有助于揭示整个物种中保存的复杂稳态网络。
