PARENT SESSION
Gene Regulation & Function

CHARACTERIZATION OF INDUCIBLE GENES IN GESTATING BOVINE UTERUS EMPLOYING cDNA MICROARRAY.

Ishiwata, Hiroko¹, Kizaki, Keiichiro¹, Nakano, Hiroko¹, Takahashi, Toru¹, imai, Kei¹, Hirasawa, Akira², Shiojima, Satoshi², Katsuma, Susumu², Suzuki, Yasuhito², Ikawa, Kouji², Tsujimoto, Gozo², Hashizume, Kazuyoshi¹, ^{1 2}

ABSTRACT- There is a bi-directional dialogue between the maternal and fetal units during the period of gestation. This communication is initiated at conception and terminated at parturition. This complex cascade of events most likely depend the intricate interaction of a multitude of genes. Hence to provide a broad overview of genes involved in above, we synthesized cDNA chip from gravid and non-gravid uteri, and the placenta. These were employed to identify inducible genes of the dam during the course of gestation in the bovine. The probes were selected at random from a library comprising of bovine caruncular, inter-caruncular, cotyledonary and inter-cotyledonary areas during the different phases of estrous cycle and early to late gestation. A total of 4,000 genes were printed onto a glass slide. The target obtained from bovine uterine endometrium tissues in pre- and post-insemination (days 30 and 60 of gestation) were labeled with either Cy3- or Cy5-dUTP. The hybridization signals were quantified using a fluorescent image analyzer. The mRNA levels of 31 gene expressions increased over five-folds during gestation while that of 13 genes declined to under half of that expressed during the estrous cycle, indicating either gestation specific and/or associated roles. The gene expression of uterine milk protein, gastrin and gastrin-releasing peptide increased significantly (P<0.05). On the other hand, vitamin D-dependent calcium binding protein decreased to approximately half. The latter two changes are consistent with previous reports (J Endocrino. 157;139-48 and Biol Reprod. 62;1779-89). Also a 50% reduction in gene expression of bovine MMP-2 was observed. This is in agreement with our earlier quantitative real time RT-PCR and northern blotting results. To conclude, this novel study in cattle availed a method to profile multitude of genes in a single experiment and indicated that both gene activation and suppression do occur concurrently in early stages of gestation. This research was supported by grants from ORCS, BRAIN and MAFF, Japan.

KEY WORDS: bovine, pregnancy, genes, microarray