Screening of T7 Phage-display cDNA Library from Liver of Microtus fortis with Extracts of Schistosomulum and Characterization of the Positive Clones
日本血吸虫童虫裂解物对东方田鼠肝脏T7噬菌体展示cDNA文库的筛选及阳性克隆分析

Microtus fortis is naturally resisitent to Schistosoma japonicum. In order to find schistosome-resistence-related genes of Microtus fortis, a T7 phage-display cDNA library from liver of Microtus fortis was screened with the soluble lysate of schistosomula. The specific phages were enriched 375-fold after 3 rounds of biopanning. Ninety-two positive clones picked at random were sequenced and 19 ESTs including 6 unreported genes were obtained. Compared with the negative phage clone control, five positive clones, No.4 (GenBank Accession No.: EW968294), No.13 (GenBank Accession No.: EW968303), No.14 (GenBank Accession No.: EW968304), No.15 (GenBank Accession No.: EW968305) and No.18 (GenBank Accession No.: EW968308) could induce significantly higher schistosomula mortality rate when co-cultivated with schistosomula. According to the function analysis and the shistosomula-killing effect in vitro, the genes encoding CASP8 and FADD-like apoptosis regulator isoform protein, alpha-2-HS-glycoprotein, M4 protein, R3H domain (binds single-stranded nucleic acids) isoform 2 and 3 previously unreported proteins (No.14, No.15 and No.18) obtained here, were schistosomiasis-resistence-related genes of Microtus fortis.