Although assisted reproductive technology is very useful to develop novel and therapeutic biomaterials for reproduction, research on molecular mechanism of folliculogenesis in pig is not clear. Therefore, the alteration of gene expression during follicular development in pigs was examined in this study. The expression of folliculogenesis-related genes was quantified in preantral (250～300 μm) and antral (>300 μm in diameter) follicles, and overall gene expression was evaluated by a genome-wide microarray. The microarray results showed that 219 genes were differentially expressed, and of those, 10 and 22 known genes showed higher and less expression at the preantral stage than at antral stages, respectively. Among them, the expression of NR0B1, PPARG, GATA4, and ANXA2 genes related to folliculogenesis was validated by quantitative real-time PCR analysis. The expression of PPARG and GATA4 genes were increased at antral stages, but a significantly stage-specific increase (p<0.05) was only detected in annexin A2 (ANXA2) in antral-stage follicles. The expression of NR0B1 genes was increased at preantral stage and these patterns of gene expression were comparable to the results obtained by microarray analysis. We propose that the systematical regulation of genes supporting specific follicle stage should be employed for improved in-vitro folliculognesis.

ABSTRACT   INTRODUCTION   MATERIALS AND METHODS    Collection of Ovarian Follicles    Generation of Affymetrix Chip Data and Analysis of Microarray    Analysis of the Relative mRNA Levels using Real-Time PCR    Statistical Analysis   RESULTS AND DISCUSSION   REFERENCES

• Jae Hee Lee(Stem Cell and Bioevaluation Laboratory, WCU Biomodulation Program, Seoul National University, Department of Obstetrics, Gynecology & Reproductive Biology, Michigan State University College of Human Medicine, Grand Rapids, MI, USA)
• Seung Tae Lee(Department of Animal Biotechnology, Kangwon National University) Corresponding author
• Heebal Kim(Department of Agricultural Biotechnology, Seoul National University)
• Jeong Mook Lim(Stem Cell and Bioevaluation Laboratory, WCU Biomodulation Program, Seoul National University, Department of Agricultural Biotechnology, Seoul National University, Cancer Research Institute, Seoul National University College of Medicine, Seoul) Corresponding author