Steroid-dependent regulation of bovine oviductal epithelial cells: a transcriptomal analysis of mRNA and miRNA

Reproductive success depends on a functional oviduct for gamete storage, maturation, fertilization, and early embryonic development. The ovarian-derived sex steroids estrogen and progesterone have been found to influence cell proliferation, differentiation and functionality of the oviduct. The objective of this study was to investigate steroidal regulation of oviductal epithelial cell function by using the Bovine Gene 1.0 ST array (Affymetrix Inc., CA) for transcriptional profiling. Our overall goals were to increase our understanding of known epithelial cell processes critical for fertility, and to identify novel genes and biochemical processes for future analysis. Transcripts were annotated using NetAffx annotation database for the Bovine gene 1.0 ST array and last updated in June 2014. Normally cycling Angus heifers were assigned to either luteal phase (LP, high progesterone, n=3) or follicular phase (FP, high estradiol, n=3) groups. Heifers in the LP group were killed between day 11 and 12 after ovulation. Heifers in the FP group were treated with 25 mg PGF2α (Lutalyse, Pfizer, NY) at 8 pm on day 6 after ovulation and killed 36 h later. Cycle stage was confirmed by ultrasonography and oviducts were collected within 20 minutes after slaughter. Epithelial cells were isolated from the ampulla and isthmus and total RNA extracted and purified using TRIzol and RNeasy columns, respectively.