REGULATION OF CARDIAC CARNITINE PALMITOYLTRANSFERASE

心脏肉碱棕榈酰转移酶的调节

• 批准号: 2399104
• 负责人: Gebre Woldegiorgis
• 金额: $ 17.89万
• 依托单位: OREGON GRADUATE INSTITUTE SCIENCE & TECH
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-09-01 至 2001-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2399104
• 关键词: aminoacid metabolism; animal genetic material tag; carnitine; chimeric proteins; developmental genetics; enzyme activity; enzyme induction /repression; fatty acid metabolism; genetic promoter element; genetically modified animals; heart metabolism; hormone regulation /control mechanism; human genetic material tag; laboratory mouse; malonyl coA; mitochondria; myocardium; palmitates; site directed mutagenesis; transferase

DESCRIPTION (Adapted from applicant's abstract): The long-term objectives of this proposal are to elucidate the regulatory mechanism of fatty acid transport and oxidation in the normal and ischemic heart. Plasma long-chain fatty acids are the primary fuel source for energy production in the normal heart. In the ischemic and reperfused myocardium, there is decreased utilization of fatty acids. Furthermore, perfusion with fatty acids results in in situ membrane damage and cardiac dysfunction. Fatty acid-induced injury to ischemic myocardium can be reduced by inhibition of carnitine palmitoyltransferase I (CPTI). Because of its central role in lipid metabolism, CPTI has attracted attention as a potential site for pharmacological intervention in the ischemic heart where elevated levels of acylcarnitines have been associated with arrhythmias; in diabetes mellitus, where fatty acid oxidation is excessive and interferes with glucose oxidation; and in human inherited CPT defects with fatal disturbances in fatty acid oxidation. Therefore, for effective pharmacotherapy of defects in cardiac fatty acid oxidation, it is imperative that we understand the biochemical and molecular mechanisms regulating CPT. The applicant has cloned, sequenced, and expressed human heart CPTI. He now plans to continue these studies with the following specific aims: 1. (a) To map the malonyl CoA and substrate binding sites in human heart CPTI by site-directed mutagenesis and chemical modification studies using residue-specific reagents. (b) To determine the structural basis for the high malonyl CoA sensitivity of human heart CPTI by constructing chimeras between heart and liver CPTI. (2) To prepare milligram quantities of expressed highly purified human heart CPTI and engineered fragments of this enzyme for structural characterization studies. (3) To characterize the promoter region of the gene coding for human heart CPTI, and to study its transcriptional regulation by hormonal, developmental, and dietary factors (a) in cardiac myocytes in vitro and (b) using a transgenic mouse model in vivo.

描述（改编自申请人的摘要）：长期目标 该提议的旨在阐明脂肪酸的调节机制 正常和缺血性心脏中的运输和氧化。 血浆长链 脂肪酸是正常能源产生的主要燃料来源 心。 在缺血性的心肌中，有降低 利用脂肪酸。 此外，带有脂肪酸的灌注结果 原位膜损伤和心脏功能障碍。 脂肪酸诱导的 通过抑制肉碱可减少缺血性心肌的损伤 棕榈酰转移酶I（CPTI）。 因为它在脂质中的核心作用 新陈代谢，CPTI吸引了人们的关注，作为潜在的地点 缺血性心脏的药理学干预升高 酰基肉碱已与心律不齐有关。在糖尿病中， 其中脂肪酸氧化过多并干扰葡萄糖 氧化；并在人类继承的CPT缺陷中，有致命的干扰 脂肪酸氧化。 因此，对于缺陷的有效药物治疗 在心脏脂肪酸氧化中，我们必须了解 调节CPT的生化和分子机制。 申请人有 克隆，测序和表达的人心CPTI。 他现在计划继续 这些研究具有以下特定目的： 1。（a）绘制人心脏中的丙二酰coA和底物结合位点 通过位置定向的诱变和化学修饰研究的CPTI使用 残留特异性试剂。 （b）确定 通过构建嵌合体的人心脏CPTI的高丙二酰coA敏感性 在心脏和肝脏CPTI之间。 （2）准备毫克量的高度纯化的人心 该酶的CPTI和工程片段用于结构表征 研究。 （3）表征人心脏编码基因的启动子区域 CPTI，并研究其通过激素调节的转录调控， 发育性和饮食因素（a）体外心肌细胞中 使用体内转基因小鼠模型。