Project description:Granulosa cells originating from three different phases of antral follicle growth were compared: growing (G), plateau (P) and atresia (A), as categorized by flow cytometry profiles of DNA. The growing and atretic conditions were each hybridized against the plateau condition as a reference in order to understand the specific biological mechanisms modulated in this class of follicles. Three-condition experiment, Plateau, Growing vs Atretic granulosa cells. Biological replicates: 4 . Dye-swap experiment.
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 study aimed to identify miRNAs expression profiles associated with growth and regression of dominant-size follicles in bovine. Follicles were collected from abattoir ovaries and their status (healthy/atretic) was assessed by measuring steroid levels and aromatase expression. Total RNA was isolated from whole follicles at different developmental stages. An heterologous microarray (Exiqon, Denmark) approach followed by RT-qPCR validation (Qiagen, UK) was used to identify and compare miRNA profiles between large healthy follicles (diameter, 13M-bM-^@M-^S16 mm, n=6) and each of small (4M-bM-^@M-^S8 mm, n=6 pools of follicles) and large atretic folllicles (13-16 mm, n=6). RNA from the above groups was hybridized to the miRCURY LNAM-bM-^DM-" microRNA Hi-Power Labeling Kit,Hy3M-bM-^DM-"/Hy5M-bM-^DM-" (Exiqon) and hybridized on the miRCURY LNAM-bM-^DM-" microRNA Array (6th gen). A total of 17 and 57 microRNAs were differentially expressed (> 2 fold, adj. P-value < 0.05) between Large Healthy and each of Small and Large Atretic follicles, respectively, a fraction of which corresponded to registered bovine miRNA sequences. A subset of 5 bovine miRNAs (miR-144, miR-202,vmiR-451, miR-652, miR-873) were confirmed by qPCR to be upregulated in Large Healthy follicles, were enriched in mural granulosa cells and their predicted targets mapped to genes involved in follicular cell proliferation and differentiation, suggesting an involvemet of this subset of microRNAs in ovarian follicle development. Six biological replicates per developmental stage (total of 18 samples) were used in a double dye microRNA microarray experiment. Samples were distributed among slides so that each experimental group was represented at least once in each slide. For each gene, mean normalized intensities (n= 6 biological replicates/group) were compared between follicle stages (SF vs LHF and LHF vs LAF).