Project description:Fertility critically depends on the gonadotropin-releasing hormone (GnRH) pulse generator, a neural construct comprised of hypothalamic neurons coexpressing kisspeptin, neurokoinin-B and dynorphin. Here, using mathematical modeling and in vivo optogenetics we reveal for the first time how this neural construct initiates and sustains the appropriate ultradian frequency essential for reproduction. Prompted by mathematical modeling, we show experimentally using female estrous mice that robust pulsatile release of luteinizing hormone, a proxy for GnRH, emerges abruptly as we increase the basal activity of the neuronal network using continuous low-frequency optogenetic stimulation. Further increase in basal activity markedly increases pulse frequency and eventually leads to pulse termination. Additional model predictions that pulsatile dynamics emerge from nonlinear positive and negative feedback interactions mediated through neurokinin-B and dynorphin signaling respectively are confirmed neuropharmacologically. Our results shed light on the long-elusive GnRH pulse generator offering new horizons for reproductive health and wellbeing.SIGNIFICANCE STATEMENT The gonadotropin-releasing hormone (GnRH) pulse generator controls the pulsatile secretion of the gonadotropic hormones LH and FSH and is critical for fertility. The hypothalamic arcuate kisspeptin neurons are thought to represent the GnRH pulse generator, since their oscillatory activity is coincident with LH pulses in the blood; a proxy for GnRH pulses. However, the mechanisms underlying GnRH pulse generation remain elusive. We developed a mathematical model of the kisspeptin neuronal network and confirmed its predictions experimentally, showing how LH secretion is frequency-modulated as we increase the basal activity of the arcuate kisspeptin neurons in vivo using continuous optogenetic stimulation. Our model provides a quantitative framework for understanding the reproductive neuroendocrine system and opens new horizons for fertility regulation
Model is encoded by Johannes and submitted to BioModels by Ahmad Zyoud.
Project description:Most dairy cows suffer uterine microbial contamination postpartum. Persistent endometritis often develops, associated with reduced fertility. We used a model of differential feeding and milking regimes to produce cows in differing negative energy balance (NEB) status in early lactation. We used Affymetrix GeneChipM-CM-^R Bovine Genome Array to investigate the global gene expression underlying negative energy balance and to identify the significantly differentially expressed genes during this process. We investigate the differences of gene expression profiles in uterine endometrial tissues between the cows with mild and severe negative energy balance.
Project description:Fertility depends on the progression of complex and coordinated postmating processes within the extracellular luminal environment of the female reproductive tract (FRT). To achieve a more comprehensive level of knowledge regarding female-derived proteins available to interact with the ejaculate, we utilized semiquantitative mass spectrometry-based proteomics to study the composition of the FRT tissue and, separately, the luminal fluid, before and after mating in Drosophila melanogaster. Our approach leveraged whole-fly isotopic labelling to delineate between female proteins and those transferred from males in the ejaculate. The dynamic mating-induced proteomic changes in the extracellular FRT luminal fluid further informs our understanding of secretory mechanisms of the FRT and serves as a foundation for establishing the roles of ejaculate-female interactions in fertility.
Project description:Infertility is a disease that affects humans and cattle in similar ways. The resemblance includes complex genetic architecture, multiple etiology, low heritability of fertility related traits in females, and the frequency in the female population. Here, we used cattle as a biomedical model to test the hypothesis that gene expression profiles of protein-coding genes expressed in peripheral white blood cells (PWBCs), and circulating micro RNAs in plasma, are associated with female fertility, measured by pregnancy outcome. We drew blood samples from 17 female calves on the day of artificial insemination and analyzed transcript abundance for 10496 genes in PWBCs and 290 circulating micro RNAs. The females were later classified as pregnant to artificial insemination, pregnant to natural breeding or not pregnant. We identified 1860 genes producing significant differential coexpression (eFDR<0.002) based on pregnancy outcome. Additionally, 237 micro RNAs and 2274 genes in PWBCs presented differential coexpression based on pregnancy outcome. Furthermore, using a machine learning prediction algorithm we detected a subset of genes whose abundance could be used for blind categorization of pregnancy outcome. Our results provide strong evidence that bloodborne transcript abundance is highly associated with fertility in females.
Project description:Most dairy cows suffer uterine microbial contamination postpartum. Persistent endometritis often develops, associated with reduced fertility. We used a model of differential feeding and milking regimes to produce cows in differing negative energy balance (NEB) status in early lactation. We used Affymetrix GeneChipÒ Bovine Genome Array to investigate the global gene expression underlying negative energy balance and to identify the significantly differentially expressed genes during this process.
Project description:The miR-200a and miR-200b families control mouse ovulation and are essential for female fertility. The ZEB1 transcription factor is a conserved target of both families and has been implicated as a key player in female fertility at multiple levels. Using gene-edited mice that express a miR-200a/b-resistant form of Zeb1, we found that derepression of Zeb1 in the female pituitary caused decreased production of luteinizing hormone and anovulatory infertility. These phenotypes were accompanied by widespread changes in pituitary gene expression characterized by decreased levels of ZEB1 targets, which include the miR-200a/b miRNAs, as expected from the miR-200a/b–ZEB1 double-negative feedback loop. Also observed were increased levels of mesenchymal genes, neuronal genes, and miR-200a/b targets. These results show that a double-negative feedback loop centered on the miRNA regulation of a single transcription factor can significantly influence the expression of thousands of genes and have dramatic phenotypic consequences.
Project description:Female infertility syndromes are among the most prevalent chronic health disorders in women, but their molecular basis remains unknown because of the complexity of oogenesis and uncertainty regarding the number and identity of ovarian factors controlling the assembly, preservation, and maturation of ovarian follicles. To systematically discover such ovarian fertility factors en masse, we employed a mouse model (Foxo3), where follicles are assembled normally but are then synchronously activated. Gene expression profiling of mutant and normal ovaries led to the identification a surprisingly large set of ovarian factors. The set included the vast majority of known ovarian factors, many of which when mutated produce female sterility phenotypes, but most were novel. Subsequent analyses revealed novel classes of ovarian factors and significant overrpresentation on the X chromosome, among other insights into the general properties of oogenesis genes and their patterns of expression. Keywords: time course, ovarian fertility factors, Foxo3 mutant
2007-08-02 | GSE8249 | GEO
Project description:Mitofusin 1 in oocyte is essential for female fertility
| PRJNA504853 | ENA
Project description:EXOSC10 regulates follicle development and female fertility in mice