Luteinizing hormone induces mouse vas deferens protein expression in the murine ovary

The aim of our study was to isolate and identify novel proteins that are in volved in the process of ovulation. To achieve this goal we used the techni que of proteome analysis. Comparison of ovary protein patterns, obtained by high resolution two-dimensional gel electrophoresis from recombinant FSH ( rFSH)- and rFSH + human CG (hCG)-treated mice, showed significant differenc es in protein spot positions and intensities. Subsequent analysis of one of these proteins was performed by mass spectrometry, resulting in the identi fication of the mouse vas deferens protein (MVDP). MVDP, which was absent i n the two-dimensional gel electrophoresis protein pattern of rFSH-primed mi ce and appeared 3 h after the hCG surge, is a member of the aldo-keto reduc tase superfamily and was originally identified in the mouse vas deferens. T his is the first study describing MVDP expression and regulation by LH in t he ovary. Northern blot analysis of female mice tissues showed that mvdp me ssenger RNA (mRNA) was only present in adrenal glands and in hCG-treated ov aries. In situ hybridization studies localized the mvdp mRNA unequivocally to ovarian thecal and interstitial cells with an expression profile startin g already 1.5 h, and decreasing 24 h, after LPI treatment. In the adrenal g lands, mvdp mRNA was not regulated by LII and localized in the cells of the zona fasciculata. In murine adrenocortical cells, a recent study proposed a detaldfying role of MVDP. MVDP might fulfill the same function in the ova ry; however, because of its strong and early transcriptional induction by L H, it is also possible that MVDP catalyses another important step during th e cascade of events occurring at the time of ovulation.