Aquarporin Water Channel Proteins in Eye

描述：（由申请人提供）：许多生理和 病理生理过程涉及水跨细胞的运输 膜。水转运蛋白的分子身份随着 水通道蛋白家族的发现。十个中的四个 已知哺乳动物水通道蛋白在眼前节中表达。这 本申请涉及调节人免疫球蛋白功能的分子机制。 AQPO、AQP 1、AQP 3和AQP 5及其在临床中的功能障碍 眼部疾病。 艾姆岛正常人眼组织水通道蛋白的分析。新试剂将 制备包括编码野生型、定点突变体的质粒，和 表位标记的人AQPO、AQP 1、AQP 3和AQP 5。对N- 人蛋白质的C-末端将在兔子中产生， 亲和纯化的。人类水通道蛋白的生物物理功能将是 在非洲爪蟾卵母细胞中表达，并在基线和 activation.人水通道蛋白将在酵母中表达并纯化， 重组到蛋白脂质体中用于渗透研究， 用于电生理学特性分析的双层，以及膜 晶体结构研究。这些水通道蛋白的分布将 在正常人眼中。 Aim II.眼部临床疾病水通道蛋白的分析。的 人水通道蛋白的分布将在来自患有以下疾病的患者的组织中定义： 白内障或干燥综合征。AQPO和AQP 5可能 有助于这些疾病将寻求包括水的缺陷， 溶质渗透，膜运输，亚基寡聚化，和 还将在啮齿动物模型中评价生理缺陷 AQPO降解和AQP 5缺乏。

DESCRIPTION: (provided by applicant): Numerous physiological and pathophysiological processes involve the transport of water across cell membranes. The molecular identity of water transporters became known with discovery of the aquaporin family of membrane water channels. Four of the ten known mammalian aquaporins are expressed in anterior segment of eye. This application addresses the molecular mechanisms regulating function of human AQPO, AQP1, AQP3, and AQP5 and dysfunction of these proteins in clinical disorders of eye. Aim I. Analysis of aquaporin proteins in normal human eye. New reagents will be prepared including plasmids encoding wild-type, site-directed mutant, and epitope-tagged human AQPO, AQP1, AQP3, and AQP5. Antibodies specific for the N- and C-termini of the human proteins will be raised in rabbits and affinity-purified. The biophysical functions of human aquaporins will be expressed in Xenopus laevis oocytes and analyzed at baseline and after activation. Human aquaporins will be expressed in yeast and purified for reconstitution into proteoliposomes for permeation studies, into planar bilayers for analysis of electrophysiological properties, and into membrane crystals for structural studies. The distribution of these aquaporins will be defined in normal human eye. Aim II. Analysis of aquaporin proteins in clinical disorders of eye. The distribution of human aquaporins will be defined in tissues from patients with cataract or Sjogren's syndrome. Basic mechanisms by which AQPO and AQP5 may contribute to these disorders will be sought including defects in water and solute permeation, membrane trafficking, subunit oligomerization, and internalization, Physiological deficits will also be evaluated in rodent models of AQPO degradation and AQP5 deficiency.