DEVELOPMENT OF GASTRIC HCL SECRETION

胃盐酸分泌的发展

• 批准号: 2140744
• 负责人: JOHN G FORTE
• 金额: $ 21.96万
• 依托单位: UNIVERSITY OF CALIFORNIA BERKELEY
• 依托单位国家: 美国
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2140744
• 关键词: adenosinetriphosphatase; autoimmune disorder; enzyme biosynthesis; enzyme structure; gastric acid; gastric mucosa; genetic regulation; glycoproteins; glycosylation; human tissue; hydrochloric acid; hydrogen; intracellular transport; laboratory mouse; laboratory rabbit; membrane transport proteins; molecular chaperones; potassium; protein purification; protein sequence; protein structure function; protein transport; secretion; sodium potassium exchanging ATPase; tissue /cell culture

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.

这项研究的总体目标是了解细胞和 胃分泌 HCl 的分子机制。 特别是 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-ATP 酶。 这些数据是 对人类胃的正常运作有直接的兴趣，并且是 直接适用于从消化性溃疡到自身免疫性疾病 疾病。 该提案有四个主要项目。 第一个项目将建立 胃 H、K-ATP 酶的合成和周转途径。 酶15 由 (x- 和 beta-亚基组成，其合成将遵循 放射性标记的氨基酸前体最终组装成成熟的 完整动物壁细胞中的功能酶。 这个特别的 细胞模型是一种很好的比较合成活性的模型 H, K-ATP 酶与 Na, K-ATP 酶密切相关，是一种关键酶 对于人体的所有细胞。 广泛应用的药理作用 将测试对 H、K-ATP 酶合成和周转的药物。 H,K-ATP酶的β亚基是一种糖蛋白，第二个 该项目将研究糖复合物的几个不寻常的特征 β-亚基。 最初的问题假发建立了β-的结构特征 人类和几种动物的亚基糖缀合物，询问 位置、组成和功能活动。异头α- 半乳糖基连接已被确定为动物β-中的“封端”糖 亚基糖缀合物，但负责这种连接的酶是 在人类中通常受到抑制。 该基因可能放松管制 在胃炎和自身免疫性疾病等疾病中的表达 调查了。 第三个项目将定义阿尔法- 和H、K-ATP酶的β-亚基。 决定的特定肽区域 全酶上的α/β相互作用和可能的功能位点将 被识别。 最终项目将开发一个体外细胞系统来评估 H, K-ATP酶的合成和运输。 当然会比较数据 与体内获得的结果相同，但细胞培养模型呈现出几种 实验优势，包括基因操作和鉴定 共处理蛋白质。