Silencing of Dicer1 by siRNA did not inhibit development up to the blastocyst stage, but decreased expression of selected transcription factors, including Oct‐4, Sox2 and Nanog, suggesting that Dicer1 gene expression is associated with differentiation processes at the blastocyst stage (Cui et al., 2007). In order to get insights into genes which may be linked with microRNA system, we compared gene expression profiles in Gapdh and Dicer1 siRNA‐microinjected blastocysts using the Applied Biosystem microarray technology. Our data showed that 397 and 737 out of 16354 genes were up‐ and down‐regulated, respectively, following siRNA microinjection (p<0.05), including 24 up‐ and 28 downregulated transcription factors. Identification of genes that are preferentially expressed at particular Dicer1 knock down embryos provides insights into the complex gene regulatory networks that drive differentiation processes in embryos at blastocyst stage.

ABSTRACT   INTRODUCTION   MATERIALS AND METHODS   RESULTS AND DISCUSSION   REFERENCES

• Jae-Dal Lee(Department of Pat Care, Hyejeon College, Hongsung-gun, Chungnam 350-702, Korea)
• Xiang-Shun Cui(Department of Animal Sciences, Chungbuk National University, Cheongju 361-763, Korea) Corresponding author