title: Molecular mechanisms regulating aquaporin-2 in kidney collecting duct.
abstract: The kidney collecting duct is an important renal tubular segment for regulation of body water homeostasis and urine concentration. Water reabsorption in the collecting duct principal cells is controlled by vasopressin, a peptide hormone that induces the osmotic water transport across the collecting duct epithelia through regulation of water channel proteins aquaporin-2 (AQP2) and aquaporin-3 (AQP3). In particular, vasopressin induces both intracellular translocation of AQP2-bearing vesicles to the apical plasma membrane and transcription of the Aqp2 gene to increase AQP2 protein abundance. The signaling pathways, including AQP2 phosphorylation, RhoA phosphorylation, intracellular calcium mobilization, and actin depolymerization, play a key role in the translocation of AQP2. This review summarizes recent data demonstrating the regulation of AQP2 as the underlying molecular mechanism for the homeostasis of water balance in the body.
authors.affiliation: Epithelial Systems Biology Laboratory, Systems Biology Center, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland; and.
authors.forename: Hyun Jun
authors.initials: HJ
authors.lastname: Jung
authors.affiliation: Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu, Korea thkwon@knu.ac.kr.
authors.forename: Tae-Hwan
authors.initials: TH
authors.lastname: Kwon
mesh_terms: D000818:Animals; D051399:Aquaporin 2 / Q000378:metabolism*; D051400:Aquaporin 3 / Q000378:metabolism; D001834:Body Water / Q000378:metabolism; D006706:Homeostasis / Q000502:physiology*; D006801:Humans; D007685:Kidney Tubules, Collecting / Q000378:metabolism*; D010766:Phosphorylation; D015398:Signal Transduction / Q000502:physiology*; D014882:Water-Electrolyte Balance / Q000502:physiology*
chemical_list: D051399:Aquaporin 2; D051400:Aquaporin 3
keywords: aquaporin-2; arginine vasopressin; body water balance; intracellular trafficking