【摘要】 大鼠Lipocalin13(rLcn13)是最近发现的一个大鼠附睾特异分泌的lipocalin家族蛋白,与男性生殖密切相关。该工作分析了rLcn13的染色体定位和基因特征,用同源模建方法获得了rLcn13蛋白的三级结构,并构建了rLcn13蛋白的原核表达系统,对rLcn13蛋白进行了可溶表达和纯化,并研究了rLcn13蛋白的配体结合特性。结果表明:(1)rLcn13蛋白在原核表达系统中能实现可溶性表达,并具有良好的三级结构;(2)rLcn13蛋白的二级结构以β-折叠为主;(3)rLcn13蛋白具有较强的视黄酸结合能力,也能结合其它一些lipocalin蛋白的配体;(4)rLcn13蛋白在大鼠附睾中可能起着视黄酸结合和转运作用,并有可能参与免疫反应。该研究为rLcn13蛋白的三维结构解析及其生理功能以及其它lipocalin家族蛋白的结构与功能关系的研究奠定了基础。更多还原

【Abstract】 Lipocalin13 is a novel epididymal-specific expressed lipocalin protein and is potentially related to male reproduction.In the present work,the location and characterization of the rat lcn13 gene were analyzed and a homology structure of the rLcn13 protein was built.Moreover,a potent expression system for rLcn13 was constructed,the rLcn13 proteins of 95% purity,were successfully obtained and the intermolecular interaction of rLcn13 with diverse ligands was detected.Our results indicated that:(1) The recombinant rLcn13 proteins can be expressed in soluble form and are well folded in the home-built E.coli expression system;(2) The three-dimensional structure of the rLcn13 protein is dominated with β-strands sheets;(3) rLcn13 possesses a high affinity for retinoic acid,it can also bind with diverse ligands;(4)rLcn13 might play a crucial role for binding and transporting retinoic acid,and is potentially involved in immunology processes.Our work will be of benefit to the three-dimensional structure determination and the function assay for rLcn13,and might be also helpful for the studies of structure-function relationships for other lipocalin proteins.更多还原