GENERATION OF ADULT STAGE SCHISTOSOMA JAPONICUM(CHINESE STRAIN) EXPRESSED SEQUENCE TAGS AND DISCOVERY OF NEW GENES

Aim To rapidly and economically obtain the new genes of adult stage Schistosoma japonicum (Chinese strain) by expressed sequence tag (EST) strategy.Methods A directional cDNA library constructed from Schistosoma japonicum (Chinese strain ) adult stage RNA was used to generate expressed sequence tags(ESTs) and the ESTs obtained were compared against EMBL-parasites database and GenBank datebase by BLASTn and BLASTx.Results A total 200 phage clones were randomly selected for generating expressed sequence tags(ESTs).From these clones,we obtained 76 EST-quality sequence.A total of 7.9% of these EST-quality sequences were identified suquence of Schistosoma japonicum,while 5.3% were putatively identified sequence of Schistosoma japonicum.A total of 22.4% of these EST-quality sequences were putatively identified sequence of Schistosoma mansoni or other organisms,and 59.2% which had no matches in the database were classified as unknow sequence.Among these EST-quality sequences,66 ESTs were successfully submitted to the dbEST at GenBank.In addition,some interesting genes were found.Conclusion Partial cDNA sequencing to get expressed sequence tags(ESTs) was a rapid and economical method to discover new genes of adult stage Schistosoma japonicum(Chinese strain).