日本血吸虫(中国大陆株)成虫表达序列标签的获取及分析

随机挑取日本血吸虫（中国大陆株）成虫cDNA文库单个重组克隆进行部分测序以获得EST（ex-pressed　sequence　tag）,获得的EST通过 BLAST程序同EMBL寄生虫数据库和GeneBank数据库进行比较及同源性分析。结果在随机挑取日本血吸虫（中国大陆株）成虫cDNA文库150个单个重组克隆中,获得了56个有价值的EST序列,其中47个在GeneBank dbEST中登录。7.1％EST序列为日本血吸虫已知序列,3.6％为日本血吸虫同源序列,曼氏血吸虫或其他生物的同源序列占25％,未知序列占55.6％。通过同源性分析可知,大多数同源序列具有看家基因功能。另外,也发现了几个有价值的基因。

Generation and Analysis of Expressed Sequence Tags of Adult Stage Schistosoma japonicum (Chinese Strain)

To rapidly and economically obtain the knowledge about adult stage Schistoma japonicum (Chinese strain) expressed genes by expressed sequence tag( EST) strategy to search for the genes which might result in the identification of new targets for chemotherapy and vaccine development. Methods: A directional cDNA library constructed from Schistosoma japonicum (Chinese strain) adult stage RNA was used to generate expressed sequence tags(ESTs) and the obtained ESTs were compared with EMBL-parasites database and GENBANK datebase by BLASTn and BLASTx. Results : A total 150 phage clones were randomly selected for generating expressed sequence tags (ESTs). From these clones, we obtained 56 EST-quality sequence. Among these EST-quality sequences, 47 ESTs were successfully submitted to the dbEST at GenBank. A total of 7. 1 % of these EST-quality sequences were identified suquence of Schistosoma japonicum , while 3.6% were homologs with homologous sequence of Schistosoma japonicum. A total of 25% of these EST-quality sequences wre sequence of Schistosoma mansoni or other oranisms, and 55.4% of the ESTs which had no matches in the database were classified as unknow sequences. Most ESTs with putative protein identified belonged to functional groups related to the general housekeeping responsibilities. In addition, some information about several interesting genes were found. Conclusion: To get expressed sequence tags(ESTs) by partial cDNA sequencing is a rapid and economical method to accumulate knowledge about the expresset genes of adult stage Schistosoma japonicum ( Chinese strain).