Construction Of A Genome Profile Involved In The Mouse Oocyte Maturation And Explore The Function Of Study During Oocyte Maturation

MicroRNAs (miRNAs) are ubiquitous small RNA regulators of gene expression, they play an important role in a series of biological processes such as cell growth, development, metabolism and so on.. The way that miRNAs display their function is to pair and target mRNA,leading to degradation of the target mRNA and translation suppression. However, the function of microRNA (miRNA) in mammal oocyte maturation have been studied little. Here, with the gene chip technology, the genomics research is on mouse oocyte maturation process .We successfully built microRNAs expression profiling of the GV and Mâ…¡oocytes. We select 49 pieces of different microRNAs which appeared to three chip do statistical analysis.There are 9 pieces of microRNAs which have more than 1.5-fold difference in expression and statistical difference of the microRNA (P <0.05).By these different gene analysis, we chose miR-21 to carry on the forward-looking function and the mechanism research.Small RNA -12 (miR-21) is non-coding small RNA molecules composed of the approximately 22 nucleotides .It participates in the post-transcriptional regulation, and located in 11 chromosomes. As a more widespread miRNA ,it early discovered in the human cell or organization and has the high homology in the humanity and the mouse.The existing reports found that tumor grow slowly after inhibiting miR-21 . In our study from the GV oocytes to Mâ…¡oocytes it has the high expression,which sugget miR-21 may participates in the mouse oocytes maturation.The oocytes maturation needs to experience the meiosis and the cytoplasmic mature in order to develop mature Mâ…¡oocytes. The first meiosis is a special stage. In this study,using the inhibitor microinjection techniques, we research on the function of miR-21 in mouse oocytes at the first meiosis.By means of living cells on their workstation, We observe meiosis process after injecting the inhibitor to GV oocytes.After inhibiting miR-21, not only the first meiosis slow down, but also the Mâ…¡o ocytes obviously reduce. This proves that miR-21 is indeed in the first meiotis of mouse oocytes. Afterward using bioinformatics we found miR-21 target to SPRY2. This was already confirmed. With reducing MAPK,SPRY2 have an effect on the first meiotis in mouse oocytes .The phenomenon was consistent with inhibiton of miR-21.In summary, the construction of comparative microRNAs profile for mouse oocyte showed us a completely new perspective to understand the process of oocyte maturation.In the follow-up study, we first found and confirmed miR-21 can influence the first meiotis in the mouse oocyte maturation by affecting the downstream gene SPYR2.