BIOSYNTHESIS AND SECRETION OF PEPTIDE HORMONES

肽激素的生物合成和分泌

基本信息

批准号：
3483256
负责人：
HOWARD S TAGER
金额：
$ 25.22万
依托单位：
UNIVERSITY OF CHICAGO
依托单位国家：
美国
项目类别：
财政年份：
1977
资助国家：
美国
起止时间：
1977-08-01 至 1991-07-31
项目状态：
已结题

项目摘要

This application describes a program of research in peptide hormone endocrinology that spans both considerations of hormone biogenesis, action and degradation and the disciplines of biochemistry, chemistry, cell biology and physiology. Emphasis in this application is placed on the bioactive peptides of the endocrine pancreas (insulin, glucagon, somatostatin and pancreatic polypeptide) and on the precedents that may be gleaned by the study of these hormones in concern. While several different projects are described, they are joined by a common focus in chemical structure, biochemical specificity and molecular interactions. Specific aims include (a) analysis of the specificity of prohormone conversion at paired and single dibasic amino acid conversion sites by model enzymes and tissue proteases, (b) determination of the structures of abnormal products of peptide hormone genes and of the causes of hyper(pro)insulinemia in selected cases where insulin gene structure appears to be normal, (c) analysis of detailed structure-function relationships and conformational changes involved in the combination of insulin with its receptor, (d) examination of the kintic and chemical heterogeneity of insulin receptors expressed in hepatic tissue, (e) determination of the molecular basis of multiple glucagon receptor populations on hepatocytes and hepatic membranes, (f) analysis of the causes and consequences of glucagon antagonism and desensitization in isolated hepatocytes, (g) determination of the biochemical basis for multiple ligand-receptor states that occur subsequent to peptide hormone-receptor interactions, (h) evaluation of the intracellular sites and biochemical correlates of peptide hormone metabolism by target tissues, (i) determintion of the existence of peptide hormone metabolites in the circulation in man, and (j) analysis of potential regulatory mechanisms that modulate ligand-receptor interactions and peptide hormone degradation in hepatic tissue. Methods involve isolated cell and membrane incubation, tissue extraction for identification of peptides and modifying enzymes, kinetic measurements of hormone-receptor interactions, biochemical and chemical analysis of detergent-solubilized receptors, radiolabeling of peptide hormones and their analogs, peptide and protein purification and analysis by molecular sieve and reverse-phase chromatography and by other methods of protein chemistry, and chemical synthesis of peptides and peptide analogs for use as receptor probes. While these studies relate most directly to investigation of diabetes and other diseases of the endocrine pancreas, the long-term objective relates more broadly to understanding how endocrine regulations leads to metabolic homeostasis and how variations in control can lead to inappropriate metabolic regulation in man.

该应用描述了肽激素研究计划涵盖激素生物发生的两种考虑，作用的内分泌学和降解和生物化学，化学，细胞的学科生物学和生理学。该应用中的重点放在内分泌胰腺的生物活性肽（胰岛素，胰血糖素，，生长抑素和胰多肽）以及可能是的先例由于关注这些激素的研究而收集的。而几个不同描述了项目，以化学方面的共同重点加入了它们结构，生化特异性和分子相互作用。具体目的包括（a）对激素的特异性分析通过成对的和单基二元氨基酸转化位点的转换模型酶和组织蛋白酶，（b）确定的结构肽激素基因的异常产物和原因在胰岛素基因结构的某些情况下，高（Pro）胰岛素血症似乎是正常的，（c）分析详细的结构功能关系和构象变化涉及胰岛素及其受体，（d）检查KINTIC和化学物质在肝组织中表达的胰岛素受体的异质性，（e）确定多胰高血糖素受体的分子基础肝细胞和肝膜的种群，（f）分析胰高血糖剂拮抗和脱敏的原因和后果孤立的肝细胞，（g）确定生化基础肽之后发生的多个配体受体状态激素受体相互作用，（H）对细胞内部位的评估和靶组织的肽激素代谢的生化相关性，（i）确定肽激素代谢产物中存在人的循环和（j）分析潜在的调节机制调节配体受体相互作用和肽激素降解在肝组织中。方法涉及孤立的细胞和膜孵育，提取肽的组织提取和修饰酶，激素受体相互作用的动力学测量，生化和洗涤剂 - 溶解受体的化学分析，放射性标记的化学分析肽激素及其类似物，肽和蛋白质纯化以及通过分子筛和逆相色谱分析以及其他蛋白质化学方法，肽和化学合成的方法和用作受体探针的肽类似物。这些研究相关最直接地调查了糖尿病和其他疾病内分泌胰腺，长期目标更广泛地与了解内分泌法规如何导致代谢稳态和控制中的变化如何导致不适当的代谢调节男人。