title: Cloning of a new aquaporin (AQP10) abundantly expressed in duodenum and jejunum.
abstract: A new aquaporin (AQP10) was identified in human small intestine. This gene encoded a 264-amino-acid protein with high sequence identity with AQP3 (53%), 9 (52%), and 7 (43%). These AQPs constitute one subfamily of AQP family that is differentiated from the other subfamily of AQP (AQP0, 1, 2, 4, 5, 6, and 8) by sequence homology. Ribonuclease protection assay and Northern blotting demonstrated almost exclusive expression of AQP10 mRNA in the duodenum and jejunum. In situ hybridization localized it in absorptive jejunal epithelial cells. Xenopus oocytes expressing AQP10 exhibited an increased osmotic water permeability in a mercury-sensitive manner. Although AQP10 belongs to the AQP subfamily, which has been characterized by permeability to water and neutral solutes such as urea and glycerol, it was not permeable to urea nor glycerol. The specific expression of AQP10 suggests its contribution to the water transport in the upper portion of small intestine.
authors.affiliation: Department of Structural Pathology, Institute of Nephrology, Niigata University, 1-757 Asahimachi-dori, Niigata 951-8510, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Hatakeyama
authors.forename: Y
authors.initials: Y
authors.lastname: Yoshida
authors.forename: T
authors.initials: T
authors.lastname: Tani
authors.forename: Y
authors.initials: Y
authors.lastname: Koyama
authors.forename: K
authors.initials: K
authors.lastname: Nihei
authors.forename: K
authors.initials: K
authors.lastname: Ohshiro
authors.forename: J I
authors.initials: JI
authors.lastname: Kamiie
authors.forename: E
authors.initials: E
authors.lastname: Yaoita
authors.forename: T
authors.initials: T
authors.lastname: Suda
authors.forename: K
authors.initials: K
authors.lastname: Hatakeyama
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D020346:Aquaporins / Q000737:chemistry / Q000145:classification / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D003001:Cloning, Molecular; D004386:Duodenum / Q000166:cytology / Q000378:metabolism*; D006801:Humans; D017403:In Situ Hybridization; D007583:Jejunum / Q000166:cytology / Q000378:metabolism*; D008969:Molecular Sequence Data; D009865:Oocytes / Q000502:physiology; D010802:Phylogeny; D014018:Tissue Distribution; D014982:Xenopus laevis
chemical_list: C438667:AQP10 protein, human; D020346:Aquaporins