烟草拟核小体组装蛋白cDNA的克隆、表达及其蛋白产物的纯化

Cloning and Expression of a Putative Tobacco Nucleosome Assembly Protein cDNA and Purification of Its Product

从烟草BY2细胞cDNA文库中筛选到核小体组装蛋白1(Nucleosomeassemblyprotein1,NAP1)的cDNA,序列分析发现该NAP1的cDNA编码374个氨基酸,与已知植物来源的NAP1同源蛋白相比具有80%以上的同源性,而且一些具有重要功能的结构域是相当保守的,如核定位信号,核输出信号,酸性结构域及异戊烯化修饰位点,重要功能结构域的存在预示了NAP1蛋白潜在的多种功能.为了深入研究NAP1的功能,应用大肠杆菌表达体系高效表达了烟草NAP1蛋白,并对表达产物进行了分离纯化.

A putative NAP1(Nucleosome assembly protein 1) cDNA was obtained through screening the library of tobacco BY2 cells. Sequence analysis showed that this tobacco NAP1 consisted of an open reading frame of 374 amino acids and several highly conserved motifs, such as nuclear localization signal, nuclear export signal, acidic region and prenylation site. More than 80% homology was found between tobacco NAP1 and the NAP1s in other plant . These characteristics indicate that this protein might be a novel member of NAP1 family in tobacco. The NAP1 cDNA was expressed in E.coli and a putative protein was purified.