Project description: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; Pâ¤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.
Project description: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.
Project description:Coordinated interactions between ovarian granulosa and theca cells are required for female endocrine function and fertility. To elucidate these interactions the regulation of the granulosa and theca cell transcriptomes during bovine antral follicle development were investigated. Granulosa cells and theca cells were isolated from small (<5 mm), medium (5-10 mm), and large (>10 mm) antral bovine follicles. A microarray analysis of 24,000 bovine genes revealed that granulosa cells and theca cells each had gene sets specific to small, medium and large follicle cells. Transcripts regulated (i.e., minimally changed 1.5-fold) during antral follicle development for the granulosa cells involved 446 genes and for theca cells 248 genes. Only 28 regulated genes were common to both granulosa and theca cells. Regulated genes were functionally categorized with a focus on growth factors and cytokines expressed and regulated by the two cell types. Candidate regulatory growth factor proteins mediating both paracrine and autocrine cell-cell interactions include macrophage inflammatory protein (MIP1 beta), teratocarcinoma-derived growth factor 1 (TDGF1), stromal derived growth factor 1 (SDF1; i.e., CXCL12), growth differentiation factor 8 (GDF8), glia maturation factor gamma (GMFG), osteopontin (SPP1), angiopoietin 4 (ANGPT4), and chemokine ligands (CCL 2, 3, 5, and 8). The current study examined granulosa cell and theca cell regulated genes associated with bovine antral follicle development and identified candidate growth factors potentially involved in the regulation of cell-cell interactions required for ovarian function. Experiment Overall Design: Granulosacell RNA samples from three groups of follicles different in size - small, medium, and large (pooled untreated ovaries) are compared between each other. Each group has 2 separate biological replicas; each replica contained pooled RNA from 20-40 ovaries from 6-10 different animals.
Project description:The objective of the study was to determine how maternal age influences the transcriptome of the dominant follicle during the preovulatory period. We tested the hypotheses that delayed ovulation in aged cows is associated with 1) altered gene expression of granulosa cells of preovulatory follicles (24 h after LH treatment) and 2) decreased synthesis of progesterone by granulosa cells of the preovulatory follicle. Granulosa cells of preovulatory follicles obtained 24 h after LH treatment from aged Hereford cows (19.0 ±2.5 years; n=3) were compared to those from young cows (9.0 ± 0.6 years; n=3) using bovine specific microarrays (EmbryoGENE-EMBV3; GPL13226). Results were confirmed by RT-qPCR. A total of 1340 genes or gene isoforms were expressed differentially (â¥2-fold change; p ⤠0.05) in aged cows vs. young cows (daughters of aged cows). In conclusion, transcriptome analysis of granulosa cells from aged cows revealed a delayed or suboptimal response to the preovulatory LH stimulus, represented by delayed cellular differentiation, luteinization and progesterone synthesis. Granulosa cells of the dominant preovulatory follicle 24 h after LH treatment were compared between 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.