Project description:A surge of luteinizing hormone (LH) from the pituitary gland triggers ovulation, oocyte maturation, and luteinization for successful reproduction in mammals. Since the signaling molecules RAS and ERK1/2 are activated by a LH surge in granulosa cells of preovulatory follicles, we disrupted Erk1/2 in mouse granulosa cells and provide in vivo evidence that these kinases are necessary for LH-induced oocyte resumption of meiosis, ovulation, and luteinization. In addition, biochemical analyses and selected disruption of the Cebpb gene in granulosa cells demonstrate that C/EBP is a critical downstream mediator of ERK1/2 activation. These mouse models provide in vivo systems in which to define the context specific and molecular mechanisms by which granulosa cells respond to LH and these mechanisms are relevant to the regulation of human fertility and infertility. Immature wild type or ERK1/2 conditonal knock-out mice were injected with 5IU equine chorionic gonadotropin (eCG)-48h followed by 5 IU hCG injection. The ovarian granulosa cells were collected at hCG 0h, 2.5h, or 4h and the gene expression pforiles were compared by microarray method.
Project description:Single-cell RNA-seq (10x) of the goat ovarian granulosa cells samples from high fertility group (>three babys per birth) and low fertility group (< two babys per birth). The goal of this project is to explore the role of ovarian granulosa cells on the fertility of goat at single cell level. We would like to investigate the role of ovarian granulosa cells on the ovulation rate which indicates fertility. Therefore the ovarian granulosa cells from different population (hihg or low fertility groups animals) were analyzed.
Project description:FOXL2 is a transcription factor essential for female fertility, expressed in somatic cells of the ovary, notably granulosa cells. In the mouse, Foxl2 deletion leads to partial sex reversal postnatally. However, deletion of the gene in 8-week-old females leads to granulosa to Sertoli cell transdifferentiation. We hypothesised that different outcomes of Foxl2 deletion in embryonic versus adult ovary may depend on a different role played across ovarian development. Therefore, we characterised the dynamics of gene expression and chromatin accessibility changes in purified murine granulosa cells across key developmental stages (E14.5, 1 and 8 weeks). We then performed genome-wide identification of FOXL2 target genes and on-chromatin interacting partners by ChIP-SICAP. We found that FOXL2 regulates more genes at postnatal stages, through the interaction with factors regulating primordial follicle activation (PFA), such as NR5A2, and others regulating steroidogenesis including AR and ESR2. As a proof of principle experiment, we chose one FOXL2 interactor, Ubiquitin specific protease 7 (USP7) and showed that deletion of this gene in granulosa cells leads to a blockage of PFA, impaired ovary development and sterility. Our study constitutes a comprehensive resource for exploration of the molecular mechanisms of ovarian development and causes of female infertility.
Project description:WNT4 is required for normal ovarian follicle development and female fertility in mice, but how its signal is transduced remains unknown. Fzd1 encodes a WNT receptor whose expression is markedly induced in both mural granulosa cells and cumulus cells during the preovulatory period, in a manner similar to Wnt4. To study the physiological roles of FZD1 in ovarian physiology and to determine if it serves as receptor for WNT4, Fzd1-null mice were created by gene targeting. Whereas rare Fzd1-/- females were sterile due to uterine fibrosis and ovarian tubulostromal hyperplasia, the majority were subfertile, producing M-bM-^IM-^H1 less pup per litter on average relative to controls. Unlike WNT4-deficient mice, ovaries from Fzd1-/- mice had normal weights, numbers of follicles, steroid hormone production and WNT4 target gene expression levels. Microarray analyses of granulosa cells from periovulatory follicles revealed few genes whose expression was altered in Fzd1-/- mice. However, gene expression analyses of cumulus-oocyte complexes (COCs) revealed a blunted response of both oocyte (Zp3, Dppa3, Nlrp5, Bmp15) and cumulus (Btc, Ptgs2, Sema3a, Ptx3, Il6, Nts, Alcam, Cspg2) genes to the ovulatory signal, whereas the expression of these genes was not altered in WNT4-deficient COCs from Wnt4tm1.1Boer/tm1.1Boer;Tg(CYP19A1-cre)1Jri mice. Despite altered gene expression, cumulus expansion appeared normal in Fzd1-/- COCs both in vitro and in vivo. Together, these results indicate that Fzd1 is required for normal female fertility and may act in part to regulate oocyte maturation and cumulus cell function, but is unlikely to function as the sole ovarian WNT4 receptor. Triplicate RNA samples from granulosa cells of Fzd1 KO mice are compared to triplicate RNA samples from granulosa cells of control Fzd1 WT mice
Project description:A surge of luteinizing hormone (LH) from the pituitary gland triggers ovulation, oocyte maturation, and luteinization for successful reproduction in mammals. Since the signaling molecules RAS and ERK1/2 are activated by a LH surge in granulosa cells of preovulatory follicles, we disrupted Erk1/2 in mouse granulosa cells and provide in vivo evidence that these kinases are necessary for LH-induced oocyte resumption of meiosis, ovulation, and luteinization. In addition, biochemical analyses and selected disruption of the Cebpb gene in granulosa cells demonstrate that C/EBP is a critical downstream mediator of ERK1/2 activation. These mouse models provide in vivo systems in which to define the context specific and molecular mechanisms by which granulosa cells respond to LH and these mechanisms are relevant to the regulation of human fertility and infertility.
Project description:The goal of this study was designe to search for the granulosa cells contribution on fertility. Single-cell RNA-seq of the goat ovarian granulosa cells samples from high fertility group (>three babys per birth) and low fertility group (< two babys per birth). And each group was divided into three subgroup based in the size of follicles: large, medium, and small follicles.
Project description:Retinoic acid (RA) is a potent inducer of cell differentiation and plays an essential role in sex-specific germ cell development in the mammalian gonad. RA is essential for male gametogenesis and hence fertility. However, RA can also disrupt sexual cell fate in somatic cells of the testis, promoting transdifferentiation of male Sertoli cells to female granulosa-like cells when the male sexual regulator Dmrt1 is absent. The feminizing ability of RA in the somatic testis suggests that RA might normally play a role in somatic cell differentiation or cell fate maintenance in the ovary. To test for this possibility we disrupted RA signaling in somatic cells of the early fetal ovary using three genetic strategies and one pharmaceutical approach. We found that deleting all three RA receptors (RARs) in the XX somatic gonad at the time of sex determination did not significantly affect ovarian differentiation, follicle development, or female fertility. Transcriptome analysis of adult triple mutant ovaries revealed remarkably little effect on gene expression in the absence of somatic RAR function. Likewise, deletion of three RA synthesis enzymes (Aldha1-3) at the time of sex determination did not masculinize the ovary. A dominant-negative RAR transgene altered granulosa cell proliferation, likely due to interference with a non-RA signaling pathway, but did not affect granulosa cell specification or fertility. Finally, culture of fetal XX gonads with an RAR antagonist blocked germ cell meiotic initiation but did not disrupt sex-biased gene expression. We conclude that RA signaling, although crucial in the ovary for meiotic initiation, is not required for granulosa cell specification, differentiation, or reproductive function.
Project description:Luteinizing hormone (LH) activation of the EGF receptor/RAS/ERK1/2 pathway is essential for ovulation and luteinization because granulosa cell depletion of Erk1/2 (Erk1/2gc-/- mice) renders mice completely infertile. Because of their potential as mediators of ERK1/2-dependent granulosa cell differentiation, we disrupted genes encoding the CCAAT/enhancer-binding proteins, (C/EBP) a and C/EBPb. Female Cebpbgc-/- mutant mice but not Cebpagc-/- mice were subfertile whereas Cebpa/bgc-/- double mutant females were sterile. Follicles failed to ovulate, ovaries were devoid of corpora lutea, luteal cell marker genes (Lhcgr, Prlr, Ptgfr, Cyp11a1 and Star) were absent and serum progesterone levels were low. Microarray analyses identified numerous C/EBPa/b target genes in eCG-hCG treated mice. At 4h post-hCG, a subset (19%) of genes altered in the Cebpa/b depleted cells was also altered in Erk1/2 depleted cells; hence they are common effectors of ERK1/2. Additional genes down-regulated in the Cebpa/b depleted cells at 8 and 24h post-hCG include known (Akr1b7, Runx2, Star, Saa3) and novel (Abcb1b, Apln, Igfbp4, Prlr, Ptgfr Timp4) C/EBP target genes including effectors of vascular cell development. Bhmt, a gene controlling methionine metabolism and expressed exclusively in liver and kidney, was high in WT luteal cells but totally absent in Cebpa/b mutant cells. Because numerous genes potentially associated with vascular development were suppressed in the mutant cells, C/EBPa/b appear to dictate the luteinization process by also controlling genes that regulate the formation of the extensive vascular network required to sustain luteal cells. Thus, C/EBPa/b mediate several aspects of granulosa cell differentiation as well as the complex process of luteinization. Five granulosa cell treatments were included: CEBPM-NM-1/M-NM-2 conditional KO ovary, eCG-treated 48h, hCG 4h wild type ovary, eCG-treated 48h, hCG 8h CEBPM-NM-1/M-NM-2 conditional KO ovary, eCG-treated 48h, hCG 8h wild type ovary, eCG-treated 48h, hCG 24h CEBPM-NM-1/M-NM-2 conditional KO ovary, eCG-treated 48h, hCG 24h