中文摘要：

柠檬酸转运蛋白（NaCT）为新发现的钠离子偶联的羧酸转运蛋白家族的一员，主要功能是负责转运三羧酸循环的中间体，近年来研究发现NaCT可能是治疗糖尿病和肥胖症的重要药物靶点。该研究构建了NaCT基因的真核表达质粒，通过稳定转染HEK293细胞，筛选得到了稳定表达NaCT的细胞系。利用RapidFire平台建立了基于NaCT的高通量药物筛选细胞模型，结果显示该模型能高效地转运柠檬酸，具有良好底物特异性和选择性，其转运能力可被Li＋激活，被4，4-二异硫氰基芪．2，2＇-二磺酸抑制。z因子计算结果为0．69，提示其适用于高通量筛选。对两种不同类型化合物库的筛选获得了一系列NaCT抑制剂，包括14个小分子化合物和15个中药组分。基于NaCT细胞模型的成功构建为高通量筛选具有抗糖尿病及肥胖症作用的先导化合物提供了一个新平台。

英文摘要：

Na＋ -coupled citrate transporter （NaCT） is a new member of solute carrier super family. NaCT transports metabolic inter- mediates of the citric acid cycle into the cell. Blocking NaCT has been suggested as a potential therapeutic approach to treat type II diabetes and obesity. An eukaryotic expression plasmid of NaCT gene was constructed, and then the Stable cell line expressing NaCT gene was established through stable transfection of HEK293 cells and monocloning cell culture. By employing Rapid. Fire mass spec- trometry assay, a sensitive and high-throughput drug screening model for NaCT has been developed, optimized and pharmacologically validated. It could transport citrate across the membrane in a sodium-dependent mode with good substrate specificity and selectivity. The citrate transport ability of this model could be completely activated by Li ＋ at 10 mmol/L, and inhibited by 4,4-＇Diisothiocyanos- tilbene-2,2-＇disulfonicacid with an IC50 of 46 μmol/L. The quality of this cell model was then assessed by using Z＇ factor which was commonly used to quantify the suitability of an assay for use in a full-scale and high-throughput screen. Calculation of the screen window coefficient generated an average Z＇ factor of 0.69 ,assuring high confidence of the model. After screening two different types of compound libraries ,a serial of NaCT inhibitors including 14 compounds and 15 herb components were identified. This HEK293 cell-based high-throughput drug screening model provided a new screening platform for identifying NaCT inhibitors as anti-diabetic or anti-obesity candidates.