Plant Trans-Golgi Network/Early Endosome pH regulation requires Cation Chloride Cotransporter (CCC1)

eLife

Yue Qu¹  Matthew Gilliham¹  Apriadi Situmorang¹  Stefanie Wege¹  W Daniel McKay¹  E Heather McFarlane² 

[1] School of Agriculture, Food and Wine, Waite Research Institute, ARC Centre of Excellence in Plant Energy Biology, University of Adelaide, Waite Campus, Adelaide, Australia;School of Biosciences, University of Melbourne, Melbourne, Australia;Department of Cell and Systems Biology, University of Toronto, Toronto, Canada;

关键词: TGN;    ion transport;    osmotic stress;    NKCC;    KCC;    endomembrane;    A. thaliana;   

DOI  :  10.7554/eLife.70701

来源: eLife Sciences Publications, Ltd

【 摘 要 】

Plant cells maintain a low luminal pH in the trans-Golgi-network/early endosome (TGN/EE), the organelle in which the secretory and endocytic pathways intersect. Impaired TGN/EE pH regulation translates into severe plant growth defects. The identity of the proton pump and proton/ion antiporters that regulate TGN/EE pH have been determined, but an essential component required to complete the TGN/EE membrane transport circuit remains unidentified − a pathway for cation and anion efflux. Here, we have used complementation, genetically encoded fluorescent sensors, and pharmacological treatments to demonstrate that Arabidopsis cation chloride cotransporter (CCC1) is this missing component necessary for regulating TGN/EE pH and function. Loss of CCC1 function leads to alterations in TGN/EE-mediated processes including endocytic trafficking, exocytosis, and response to abiotic stress, consistent with the multitude of phenotypic defects observed in ccc1 knockout plants. This discovery places CCC1 as a central component of plant cellular function.

【 授权许可】

CC BY