未知基因组及蛋白质序列数据库有限的物种的蛋白质组学分析是当前一些非模式生物物种蛋白质组学研究领域的瓶颈之一.基于同源性搜索的BLAST方法(MS BLAST),是近年新发展起来的一种用于未知基因组的蛋白质鉴定的搜索工具,已成功应用于许多未知基因组物种的蛋白质鉴定.SPITC化学辅助方法是本实验室建立的一种改进的de novo质谱测序方法.采用MS BLAST方法对经Mascot软件数据库搜索未能鉴定到的19个金鱼胚胎蛋白质进行鉴定,其中12个蛋白质是直接测序后进行MS BLAST搜索得到的结果,另外7个蛋白质是联合MS BLAST和SPITC衍生方法得到的鉴定结果.实验结果证明,采用MS BLAST方法进行蛋白质的跨物种鉴定具有可行性和可靠性,给蛋白质的跨物种鉴定提供了一条新的途径.
Protein identification is a significant bottleneck in proteomic researches of some species with unknown genomes or uncompleted protein database at present. Mass spectrometry driven BLAST ( MS BLAST) is a sequence similarity searching tool, which has been developed in recent years and successfully applied to the identification of protein from species with unsequenced genomes. SPITC derivation is an improved de novo sequencing method by Mass Spectrometry. Combining these two methods, 19 proteins of goldfish embryos not identified by Mascot searching were successfully identified by MS BLAST. Among 19 proteins, 12 were identified by MS BLAST searching, while the other 7 were identified by MS BLAST searching based on de novo sequencing of SPITC derivated peptides. This strategy has been proved feasible and reliable for protein identification of goldfish embryos, and provides a new pathway for protein cross-species identification of species with unsequenced genomes.