Bioinformatics Analysis Of Evolutionary Conservatism And Target Gene Function Of Drosophila MiRNA - 92a

miRNA is a kind of～22 necleotides long endogeneous non-coding RNAs and plays an important role in the gene expression. The evolutionary conservation and diversity of miRNA also lead to evolution of species and phenotypic differentiation between species. Drosophila melanogaster acting as the important research model of genetic, insect and human natrual immunity and human disease, has received extensive attention. Previous research has shown that hsa-miRNA17-92 plays important regulation role in the occurrence and development of tumor cells, the abnormal expression of dme-miRNA-92 will trigger its phenotype change; So, Further function research of dme-miRNA-92a has important significance for the hsa-miRNA17-92 regulation mechanism. Given this, we conducted bioinformatics analysis of dme-miRNA-92a conversation and its target gene function. Besides, we conducted dual-luciferase reporter system to examine the target relationship. Results are as follows:1. Bioinformatics analysis showed that Drosophila melanogaster miRNA-92a is highly conserved. Its homologous miRNAs have been found in 75 species. Besides, there are 11 species have its homologous gene in 13 primates species; there are 24 species have its homologous gene in 26 hexapoda species(now available in miRBase database). These research showed that the study of Drosophila melanogaster miRNA-92a is helpful to research of primate and hexapoda miRNA-92a.2. We used TargetScan software to search the miRNA-92a target gene, there are 349,667 and 893 genes in Drosophila melanogaster, Mus musculus and Homo sapiens, respectively. Further bioinformatics analysis showed that there are only 23 homologous genes exist in three species. We used PANTHER software to do cluster analysis for above 23 target gene, miRanda and PicTar software to examine target relationship, then five important transcription factors(kay, Sara, grn, en and CrebA)were obtained. These Drosophila melanogaster transcription factors have involved in some important pathway regulation. For example, kay involved in the regulation of Imd and planar cell polarity; CrebA involved in the regulation of phosphorylation process. These results indicate that study of dme-miRNA-92a and its target gene have important guidance for research of primate miRNA.3.We conducted the dual-luciferase reporter system to verify the relationship between dme-miRNA-92a and target gene(kay). The experiment results in vitro confirmed the credible relationship of dme-miRNA-92a and kay gene by detecting the change of Firefly luciferase and Ranilla luciferase. Drosophila melanogaster’s kay is the homologous gene of human proto-oncogene fos, hence, the further research of dme-miRNA-92a and kay relationship have theoretical and practical guidance for the function of hsa-miRNA-92a in tumor occur mechanism.To sum up, the results have not only provided important foundation for further function research of dme-miRNA-92a, but also offered helpful enlightenment for hsa-miRNA-92a.