Comparison Of The Gene Expression Profiles In The Mii Eggs From Blocking And Non-blocking Strain Mice Respectively And Effects Of FGF7 On The In Vitro Development Of Mouse Preimplantation Embryo

Objective:To comparis the gene profiles in the MII eggs from blocking and non-blocking strain mice,and investigate the effects of FGF7 on the in vitro development of mouse preimplantation embryo.Methods:1. Mouse cDNA microarray (Affymetric GeneChip Mouse Genome 430 2.0) was applied to analyse the gene expression profiles of KM and B6C3F1 mouse eggs, and then Real-time PCR was used to validate some different genes.2. Reverse transcription polymerase (RT-PCR), Immunofluorescence staining and confocal lascer scanning microscope were used to detect the expression and distribution of FGFR1, FGFR2 and FGFR3.3. KM 1-cell embryos were cultured in M16 media which were added different concentrations of FGF7 protein. The effects of FGF7 on the development of preimplantation embryo in vitro were observed, and the percentage of mouse embryos developing from 2- to 4-cell stage was used as evaluation criteria.Results:1. Of 45037 genes in the mouse cDNA microarray, 3144 genes were differentially expressed between KM and B6C3F1 mouse MII oocytes, including 1818 up-regulated genes and 1326 down-regulated genes for B6C3F1 mice. We retain the gene which signal intensity exceed 200, containing 793 up-regulated genes and 202 down-regulated genes for B6C3F1 mice MII oocytes. These genes involved in regulation of gene transcription, oxidation reduction, protein biosynthesis, protein transport, protein amino acid phosphorylation, development processes were up-regulated in B6C3F1 mouse MII oocytes . 2. FGFR1, FGFR2 and FGFR3 mRNA were detectable in both the oocytes and the preimplantation embryos of KM mice by using RT-PCR. Immunofluorescence staining analysis showed that FGFR1 and FGFR3 were mainly distrubuted in the peripheral cytoplasm of the oocytes and preimplantation embryos. However, FGFR2 were located uniformly in the cytoplasm of the oocytes and preimplantation embryos.3. KM 1-cell embryos were cultured in M16 media which were added by different concentrations of FGF7 protein. The percentages of mouse embryos developing from 2- to 4-cell stage had significant differences comparing to the control. In vitro, most of KM 1-cell embryos were arrested in 2-cell stages when cultured in M16 media, while most of KM 1-cell embryos could develop beyond 2-cell stage and to 4-cell in experimental group.Conclusion:These maternal genes involved in regulation of gene transcription, protein biosynthesis and transport, oxidation reduction, protein amino acid phosphorylation, development processes were up-regulated in B6C3F1 mouse MII oocytes, which might have an effect on the in vitro development of mouse preimplantation embryo. The expression of FGFR1, FGFR2, FGFR3 in oocytes and preimplantation embryo and the promotive effects of FGF7 on the in vitro development of KM mouse preimplantation embryo confirmed the effects of maternal genes on the development of mouse preimplantation embryo further.