2004 Fiscal Year Final Research Report Summary
Studies on therapuetic strategy of renal channel diseases.
Project/Area Number |
13307030
|
Research Category |
Grant-in-Aid for Scientific Research (A)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Kidney internal medicine
|
Research Institution | Tokyo Medical and Dental University |
Principal Investigator |
SASAKI Sei Tokyo Medical and Dental University, professor, 大学院・医歯学総合研究科, 教授 (60170677)
|
Project Period (FY) |
2001 – 2004
|
Keywords | water channel / aquaporin / Chloride channel / channel disease / intracellular vesicle / knockout mice |
Research Abstract |
1.Studies on the molecular pathogenesis of autosomal-dominant type nephrogenic diabetes insipidus (AD-NDI). We found five families of AD-NDI. Sequencing of AQP2 gene revealed that there were heterozygous frame-shift mutations in all patients, which resulted in the addition of 61 amino acids to the carboxy terminus of AQP2. In contrast to the apical localization of the wild-type AQP2 expressed in MDCK cells, the disease-causing mutants were localized to the basolateral membranes. Furthermore, the mutants recruited the wild-type AQP2 to the basolateral membrane when co-expressed, showing dominant-negative effect. We also found that a di-luecine motif in the mutant was responsible for the basolateral sorting. To confirm whether the above mentioned mechanism really worked in vivo, we generated by gene targeting a knock-in mouse that expressed the mutant AQP2. As expected, the knock-in mice showed AD-NDI. Apical localization of the wild-type AQP2 was significantly impaired by the mutant AQP2
… More
expression. Further analysis of this mouse model will help to clarify the molecular mechanisms of AD-NDI in vivo and to develop strategy for the treatment of AD-NDI. 2.Generation of AQP11 and AQP12 knockout mice. AQP11 and AQP12 were identified by us using database search. Although AQP11 was ubiquitously expressed, AQP 12 was found to be a pancreas-specific AQP. They were also identified as intracellular AQPs by transient expression studies in cultured cells and Xenopus oocytes. To identify their physiological roles in vivo, we generated AQP11 and AQP12 knock-out mice by targeted gene disruption. At present, renal and pancreatic functions are analyzed in AQP11 and AQP12 knockout-mice, respectively. 3.Analysis of a disease-causing mutant WNK4. Mutations of WNK1 and WNK4 kinases were reported to be responsible for pseudohypoaldosteronism type II (PHAII) by positional cloning strategy. However, the molecular pathogenesis of PHAII by these mutations was not clarified. We demonstrated that the mutant WNK4 increased paracellular chloride permeability and claudin phosphorylation in MDCK cells. These results supported the previously postulated "chloride shunt" hypothesis in PHAII and clarified the molecular mechanisms of PHAII. Less
|
Research Products
(41 results)
-
-
-
-
-
-
-
[Journal Article] Aquaporin-2 trafficking is regulated by PDZ-domain containing protein SPA-1.2004
Author(s)
Noda Y, Horikawa S, Furukawa T, Hirai K, Katayama Y, Asai T, Kuwahara M, Katagiri K, Kinashi T, Hattori M, Minato N, Sasaki S.
-
Journal Title
FEBS lett 568
Pages: 139-145
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
[Journal Article] CLC-3 deficiency leads to phenotypes similar to human neuronal ceroid lipofuscinosis.2002
Author(s)
Yoshikawa M, Uchida S, Ezaki J, Rai T, Hayama A, Kobayashi K, Kida Y, Noda M, Koike M, Uchiyama Y, Marumo F, Kominami E, Sasaki S.
-
Journal Title
Genes Cells 7(6)
Pages: 597-605
Description
「研究成果報告書概要(欧文)」より
-
-
-
-
-
-
-
-
-
-
[Journal Article] Three families with autosomal dominant nephrogenic diabetes insipidus caused by aquaporin-2 mutations in the C-terminus.2001
Author(s)
Kuwahara M, Iwai K, Ooeda T, Igarashi T, Ogawa E, Katsushima Y, Shinbo I, Uchida S, Terada Y, Arthus MF, Lonergan M, Fujiwara TM, Bichet DG, Marumo F, Sasaki S.
-
Journal Title
Am J Hum Genet 69
Pages: 738-748
Description
「研究成果報告書概要(欧文)」より
-
-
-