Fatty Acid Binding Proteins-Ligand Specificity

描述（由申请方提供）：长链脂肪酸（LCFA）和LCFA-CoA是脂质代谢中的重要代谢中间体，也是参与LCFA、脂蛋白和/或葡萄糖代谢的核转录因子（PPARalpha、HNF 4 alpha）的配体调节剂。虽然研究纯化的脂肪酸结合蛋白（FABPs）在体外和/或与过表达，转化细胞培养表明LCFA代谢的功能，在体内的个别FABPs的生理作用尚未解决。肝细胞（肝细胞）大量表达三种结合LCFA和LCFA-CoA的蛋白质：肝脂肪酸结合蛋白（L-FABP）、固醇载体蛋白-2（SCP-2）和固醇载体蛋白-x（SCP-x）。本申请的目的是：（i）消除LCFA/LCFA-CoA结合蛋白的单独合成，并在指示时在基因消除小鼠中繁殖;（ii）检查这些蛋白在培养的肝细胞和体内直链和支链LCFA代谢中的单独作用;和（iii）检查LCFA/LCFA-CoA结合蛋白可能发挥作用的两种潜在核调节机制。具体目标集中在培养的肝细胞和基因靶向小鼠上，以检查： 目标1.在基因消融小鼠和体内培养的肝细胞中的LCFA摄取和细胞内LCFA/LCFA-CoA转运。 目标2.对照组和基因消融小鼠培养肝细胞中L-FABP、LCFA/LCFA-CoA向细胞核的运输、细胞核内的分布以及与PPAR α和HNF 4 α的相互作用。 目标3。基因消融小鼠和体内培养肝细胞线粒体、过氧化物酶体和内质网中LCFA的氧化。 目标4。在基因消融小鼠和体内培养的肝细胞中储存或分泌的酯化。 随着对细胞内脂肪酸和葡萄糖代谢之间相互关系的认识不断提高，这些研究的结果将有助于我们了解糖尿病以及脂质代谢疾病（包括动脉粥样硬化、肥胖和心脏病）的相关因素。

DESCRIPTION (provided by applicant): Long chain fatty acids (LCFAs) and LCFA-CoAs serve as important metabolic intermediates in lipid metabolism and as ligand regulators of nuclear transcription factors (PPARalpha, HNF4alpha) involved in LCFA, lipoprotein, and/or glucose metabolism. Although studies with purified fatty acid binding proteins (FABPs) in vitro and/or with overexpressed, transformed cells in culture suggest functions in LCFA metabolism, physiological roles of individual FABPs in vivo are unresolved. Liver cells (hepatocytes) express three proteins in abundance that bind both LCFAs and LCFA-CoAs: liver fatty acid-binding protein (L-FABP), sterol carrier protein-2 (SCP-2), and sterol carrier protein-x (SCP-x). The objective of this application is to: (i) eliminate synthesis of LCFA/LCFA-CoA binding proteins individually, and where indicated, multiply in gene-ablated mice; (ii) examine individual role(s) of these proteins in metabolism of straight- and branched-chain LCFAs in cultured hepatocytes and in vivo; and (iii) examine two potential nuclear regulatory mechanism(s) whereby the LCFA/LCFA-CoA binding proteins may exert effects. The specific aims are focused on cultured hepatocyes and gene-targeted mice to examine: Aim 1. LCFA uptake and intracellular LCFA/LCFA-CoA transport in hepatocytes cultured from gene-ablated mice and in vivo. Aim 2. Trafficking of L-FABP, LCFAs/LCFA-CoAs to nuclei, distribution within nuclei, and interaction with PPARalpha and HNF4alpha in cultured hepatocytes from control and gene-ablated mice. Aim 3. Oxidation of LCFAs in mitochondria, peroxisomes, and endoplasmic reticulum of cultured hepatocytes from gene-ablated mice and in vivo. Aim 4. Esterification for storage or secretion in cultured hepatocytes from gene-ablated mice and in vivo. With the growing awareness of interrelationships between intracellular fatty acid and glucose metabolism, results from these studies will contribute to our understanding of factors involved in diabetes as well as diseases of lipid metabolism, including atherosclerosis, obesity, and heart disease.