DEVELOPMENT OF GASTRIC HCL SECRETION

这项研究的总体目标是了解细胞和 胃分泌HCl的分子机制。特别之处 研究重点将确定其结构、功能和合成途径。 负责HCl分泌的酶H，K-ATPase。这些数据是 对人类胃的正常运作有直接的影响，并且是 直接适用于从消化性溃疡到自身免疫的各种疾病 疾病。 该提案有四个主要项目。第一个项目将建立 胃H，K-ATPase合成和周转途径。酶15 由(x-和β-亚基组成，其合成将从 放射性标记氨基酸前体到成熟期的最终组装 完整动物壁细胞中的功能酶。这个特别的 细胞模型是比较细胞合成活性的一个很好的模型 H，K-ATPase与Na，K-ATPase密切相关的关键酶 对人体内的所有细胞来说。广泛使用的药理作用 试剂对H，K-ATPase的合成和周转将进行测试。 H，K-ATPase的β亚基是一种糖蛋白，第二个 该项目将研究糖共轭化合物的几个不同寻常的特征 β亚基。最初的问题将建立Beta-的结构特征- 人类和几种动物的亚基糖偶联物，询问 位置、组成和功能活动。反常的阿尔法- 半乳糖基连接已被确定为动物β-糖链中的一种‘封顶’糖。 亚单位糖共轭，但负责这种连接的酶是 通常在人类体内被抑制。可能解除对该基因的管制 在胃炎和自身免疫性疾病等情况下表达 调查过了。 第三个项目将定义阿尔法和阿尔法之间的互动地点。 和H，K-ATPase的β亚基。决定的特定多肽区域 α/β相互作用和全酶上可能的功能位点 被指认出来。 最后的项目将开发一种用于评估的体外细胞系统 H，K-ATPase的合成和运输。当然，数据将被比较 与体内获得的结果相同，但细胞培养模型呈现出几个 实验优势，包括基因操作和鉴定 共同处理蛋白质。

The overall goal of this research is to understand the cellular and molecular mechanisms of HCl secretion by the stomach. The particular research focus will define structure, function and synthetic pathway of the enzyme responsible for HCl secretion, the H, K-ATPase. These data are of immediate interest to the normal operation of the human stomach, and are directly applicable to disorders ranging from peptic ulcer to autoimmune disease. The proposal has four major projects. The first project will establish the pathway for synthesis and turnover of gastric H, K-ATPase. The enzyme 15 composed of (x- and beta-subunits whose synthesis will be followed from radiolabeled amino acid precursors to the final assembly of the mature functional enzyme in the parietal cell of intact animals. This particular cell model is an excellent one in which to compare synthetic activities of H, K-ATPase with the very closely related Na, K-ATPase a critical enzyme for all cells in the human body. The role of widely used pharmacological agents on the synthesis and turnover of H, K-ATPase will be tested. The beta-subunit of the H, K-ATPase is a glycoprotein, and the second project will study several unusual features of glycoconjugates within the beta-subunit. Initial questions wig establish structural features of beta- subunit glycoconjugates for human and several animals, asking about location, composition and functional activity. The anomeric alpha- galactosyl linkage has been identified as a 'capping' sugar in animal beta- subunit glycoconjugates, but the enzyme responsible for this linkage is normally suppressed in human. Possible deregulation of the gene for expression in conditions such as gastritis and autoimmune disease will be investigated. The third project will define the sites of interaction between the alpha- and beta- subunits of H, K-ATPase. Specific peptide regions that determine alpha/beta interaction and possible functional sites on the holoenzyme will be identified. The final project will develop an in vitro cell system for evaluating synthesis and trafficking of H, K-ATPase. Data will of course be compared with those obtained in vivo, but the cell culture model presents several experimental advantages, including genetic manipulation and identification of co-processing proteins.