GLYCEROL-3-PHOSPHATE ACYLTRANSFERASE

3-磷酸​​甘油酰基转移酶

• 批准号: 2888806
• 负责人: TAL M LEWIN
• 金额: $ 3.67万
• 依托单位: UNIV OF NORTH CAROLINA CHAPEL HILL
• 依托单位国家: 美国
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-05-18 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/2888806
• 关键词: Animalia; active sites; acyltransferase; enzyme activity; enzyme mechanism; fatty acid metabolism; lipid biosynthesis; mitochondria; mitochondrial membrane; phosphorylation

Obesity, diabetes mellitus, and atherosclerotic heart disease are associated with increases in triacylglycerol synthesis. The initial and committed step in this pathway is the acylation of sn-glycerol-3 phosphate to form 1 acyl-sn-glycerol-3-phosphate which is catalyzed by glycerol-3-phosphate acyltransferase GPAT. Since this step is believed to be rate limiting, GPAT is likely to play the pivotal role in regulating triacylglycerol and phospholipid biosynthesis. The specific purpose of this research proposal is to understand the activity, regulation, and requirement for mitochondrial GPAT in the context of its control of glycerolipid biosynthesis. To study GPAT activity, I will use oligonucleotide directed mutagenesis to identify the critical amino acids required for GPAT action. Protease accessibility studies will determine the topography of GPAT in the outer mitochondrial membrane and thereby aid in understanding both activity and regulation. GPAT regulation will be examined directly by determining if it is phosphorylated and inactivated during nutritional states associated with decreased triacylglycerol synthesis. Interactions between GPAT and other enzymes of glycerolipid biosynthesis will be examined through use of the yeast two-hybrid system and cross-linking experiments. Finally, the role of mitochondrial GPAT in directing the fate of fatty acids during different nutritional and hormonal states will be examined in tissue culture systems overexpressing or lacking mitochondrial GPAT.

肥胖、糖尿病和动脉粥样硬化性心脏病是 与三酰甘油合成增加有关。首字母和 这个途径的关键步骤是sn-甘油-3的酰化。 磷酸盐生成1-酰基-SN-甘油-3-磷酸，其催化作用 甘油-3-磷酸酰基转移酶GPAT。因为人们相信这一步 作为速率限制，GPAT可能在以下方面发挥关键作用 调节三酰甘油和磷脂的生物合成。具体的 这项研究建议的目的是了解活动， ITS背景下对线粒体GPAT的调控和要求 甘油脂生物合成的控制。为了研究GPAT活动，我将 利用寡核苷酸定向突变鉴定关键氨基酸 GPAT作用所需的酸。蛋白酶可及性研究将 测定线粒体膜外膜GPAT的形态 从而有助于理解活动和监管。GPAT 监管将直接受到审查，方法是确定是否 在营养状态期间被磷酸化和失活 三酰甘油合成减少。GPAT和GPAT之间的相互作用 甘油脂生物合成的其他酶将通过使用进行检测 对酵母双杂交系统进行了研究和交联化实验。最后， 线粒体GPAT在控制脂肪酸命运中的作用 在不同的营养和荷尔蒙状态下将在 组织培养系统过度表达或缺乏线粒体GPAT。