Maternal age related changes in transcriptome of bovine granulosa cells of the dominant follicle at the time of selection

The objective was to determine age-associated changes in the transcriptome of granulosa cells recovered from the dominant follicle at the time of selection. Granulosa cells were collected from the dominant follicle of aged and young cows after ovariectomy (15 ±1.5 years, n=3 and 6 ± 1.1 years, n=3), or ultrasound-guided follicle aspiration (16±2.1 years, n=4 and 7±1.2 years, 6 ± 1.1 years, n=4) 3-days after ovulation (Day 0). Messenger-RNA was extracted, amplified, labeled with florescent dyes, and hybridized with bovine-specific microarrays (GEO accession # GPL13226). Target intensities were analyzed to determine differential gene expression in granulosa cells from aged vs. young cows. A total 169 genes were differentially expressed (≥ 2 fold-change; P≤0.05) between age groups. In conclusion, granulosa cells collected at the time of selection of the dominant follicle exhibited age-related changes in the transcriptome that may explain follicle-associated loss of oocyte competence in aged cows. Granulosa cells of the dominant follicle at the time of selection (aged vs.young cows). Three biological replicates (each composed of one aged and one young cow). 3 Three technical replicate (dye swap). One biological or technical replicate per array.