Molecular Biology And Bioinformatics Of Schistosoma Japonicum: Research And Application

Objective To research and explore for active substance that could boost proliferation in the cultured cells from adult Schistosoma japonicum, cells were cultivated and observed from adult S. japonicum, could offer evidence and reference to obtain illimitably proliferative cell line of adult S. japonicum in vitro. To establish a sensitive and specific PCR assay for detecting S. japonicum miracidium, pestilential water was imitated to concentrate miracidium and extract its DNA. The 2-D figure and 3-D figure of S. japonicum DNA sequences were described. They reflected the biological characteristics and basic laws hided in DNA sequences at a different angle. And they also provided the basis for validating the laws and exploring more prefound biotic essence of next biological experiments.Methods The mice 7-8 weeks after infection were killed randomly. Adult S. japonicum were randomly divided into one group per 20 to cut up and cultivate by aseptic technique. And took photographs and wrote down the results by Olympus inverted microscope. In order to make sure that the cultured cells from adult S. japonicum were vital, two groups cultured cells were chose randomly to prepare chromosome observed by Olympus-CX31 microscope. Add bFGF, IL-2 and Con A in turn to the culture bottles divided into three groups randomly, then label one by one and cultivate in the same condition, observe and take photographs by Olympus camera and Olympus inverted microscope at last.Eggs of S. japonicum were harvested from infected livers of the mice 6-8 weeks after infection, which were then incubated with water and collected consecutively by centrifugalization in the centrifuge tube. The miracidium DNA of S. japonicum was extracted with Proteinase K-phenol method. Based on 18S small subunit ribosomal DNA (18S rDNA) gene of S. japonicum in GenBank, a polymerase chain reaction(PCR) assay for detecting miracidium of S. japonicum in water was established by Primer Premier 5.0 and Oligo 6 and set up the negative control for evaluating the specificity and mass detection experiments of PCR assay were performed. The PCR results were judged with the naked eyes and elect rophoretic analysis.Set four directions as A, T, G and C in coordinate system to describe the 2-D figure of S. japonicum DNA sequences. Four equidistant horizontal lines were draw up marked with A, C, G and T. Each line was marked with point according to DNA sequences before linking them together. It was four horizontal lines figure of DNA sequences. Make three-dimensional vector (1,0,0), (0,1,0), (0,0,1) and (1,1,1) as A, C, G and T in turn. Then edit each point coordinate of DNA sequences by the vector. Each vector was marked with point according to point coordinates of DNA sequences before linking them together. It was 3-D figure of S. japonicum DNA sequences. At last project 3-D figure of S. japonicum DNA sequences on the two dimensional plane and compare with each other. Based on DNA sequences and its characteristic sequences, double horizontal lines figure and 2-D figure of three characteristic sequences of DNA sequences were draw up. The directed graph on account of Nandy 2-D figure of DNA sequences was described like the 2-D figure of DNA sequences, not line segment but arrow to link points together.Results (1)The cultured cells from adult S. japonicum were globose and vivid by Olympus inverted microscope. The number of the cultured cells were increasing with time without mitogenetic substance. But they were not proliferative and reproductive with the passage of time. Both two groups cultured cells we chose randomly to prepare chromosome had metaphase of S. japonicum observed by Olympus-CX31 microscope.And the number of chromosome was 8. Not all mitogenetic substance could boost proliferation in the cultured cells from adult S. japonicum. The influence of bFGF was invisible. But the influences of IL-2 and Con A were visible, and the best was IL-2.(2)After PCR, the positive signal with an approximate length of 463bp was observed with miracidium of S. japonicum. By contrast, no positive signal was observed for the negative control. Experiments showed that the minimum DNA concentration of S. japoncium miracidium to be detected was 62.5 pg/μL.(3)The 2-D figure, four horizontal lines figure, 3-D figure, double horizontal lines figure and directed graph were draw up in turn, which were analyzed and compared with each other. Conclusion The cultured cells from adult S. japonicum were not proliferative and reproductive without mitogenetic substance. The influence of bFGF was invisible. But the influences of IL-2 and Con A were visible, and the best was IL-2. The PCR assay for trace detection of S. japonicum miracidium shows high sensitivity and specificity. The 2-D figure and 3-D figure of S. japonicum DNA sequences could reflect the biological characteristics hided in DNA sequences at a different angle. The 2-D figure of S. japonicum DNA sequences lost information due to degeneracy. But the 3-D figure of S. japonicum DNA sequences avoided intersecting or overlapping at itself. The degeneracy of the directed graph was lower than the undirected graph's. Even it disappeared on certain conditions, and moreover, what we saw was just the history of transmigration following to the organismic sequences. Therefore, the directed graph stimulated the imagery thinking of people more easily in favour of getting characteristics of the organismic sequences quickly.