FOXL2 is a Progesterone Target Gene in the Endometrium of Ruminants

Forkhead Box L2 (FOXL2) is a member of the FOXL class of transcription factors, which are essential for ovarian differentiation and function. In the endometrium, FOXL2 is also thought to be important in cattle; however, it is not clear how its expression is regulated. The maternal recognition of pregnancy signal in cattle, interferon-Tau, does not regulate FOXL2 expression. Therefore, in the present study, we examined whether the ovarian steroid hormones that orchestrate implantation regulate FOXL2 gene expression in ruminants. In sheep, we confirmed that FOXL2 mRNA and protein was expressed in the endometrium across the oestrous cycle (day 4 to day 15 post-oestrus). Similar to the bovine endometrium, ovine FOXL2 endometrial expression was low during the luteal phase of the oestrous cycle (4 to 12 days post-oestrus) and at implantation (15 days post-oestrus) while mRNA and protein expression significantly increased during the luteolytic phase (day 15 post-oestrus in cycle). In pregnant ewes, inhibition of progesterone production by trilostane during the day 5 to 16 period prevented the rise in progesterone concentrations and led to a significant increase of FOXL2 expression in caruncles compared with the control group (1.4-fold, p < 0.05). Ovariectomized ewes or cows that were supplemented with exogenous progesterone for 12 days or 6 days, respectively, had lower endometrial FOXL2 expression compared with control ovariectomized females (sheep, mRNA, 1.8-fold; protein, 2.4-fold; cattle; mRNA, 2.2-fold; p < 0.05). Exogenous oestradiol treatments for 12 days in sheep or 2 days in cattle did not affect FOXL2 endometrial expression compared with control ovariectomized females, except at the protein level in both endometrial areas in the sheep. Moreover, treating bovine endometrial explants with exogenous progesterone for 48h reduced FOXL2 expression. Using in vitro assays with COS7 cells we also demonstrated that progesterone regulates the FOXL2 promoter activity through the progesterone receptor. Collectively, our findings imply that endometrial FOXL2 is, as a direct target of progesterone, involved in early pregnancy and implantation

Cloning and functional expression of the rabbit transferrin gene promoter

International audienc

Mass production of genetic markers from a limited number of sorted chromosomes

International audienc

Cloning, transcription and chromosomal localization of the porcine whey acidic protein gene and its expression in HC11 cell line

Chantier qualité spécifique "Auteurs Externes" département de Génétique animale : uniquement liaison auteur au référentiel HR-AccessInternational audienc

Preterm birth affects both surfactant synthesis and lung liquid resorption actors in fetal sheep

International audienceIntroduction: After birth, the lungs must resorb the fluid they contain. This process involves multiple actors such as surfactant, aquaporins and ENaC channels. Preterm newborns often exhibit respiratory distress syndrome due to surfactant deficiency, and transitory tachypnea caused by a delay in lung liquid resorption. Our hypothesis is that surfactant, ENaC and aquaporins are involved in respiratory transition to extrauterine life and altered by preterm birth. We compared these candidates in preterm and term fetal sheeps.Materials and methods: We performed cesarean sections in 8 time-dated pregnant ewes (4 at 100 days and 4 at 140 days of gestation, corresponding to 24 and 36 weeks of gestation in humans), and obtained 13 fetal sheeps in each group. We studied surfactant synthesis (SP-A, SP-B, SP-C), lung liquid resorption (ENaC, aquaporins) and corticosteroid regulation (glucocorticoid receptor, mineralocorticoid receptor and 11-betaHSD2) at mRNA and protein levels.Results: The mRNA expression level of SFTPA, SFTPB and SFTPC was higher in the term group. These results were confirmed at the protein level for SP-B on Western Blot analysis and for SP-A, SP-B and SP-C on immunohistochemical analysis. Regarding aquaporins, ENaC and receptors, mRNA expression levels for AQP1, AQP3, AQP5, ENaCα, ENaCβ, ENaCγ and 11βHSD2 mRNA were also higher in the term group.Discussion: Expression of surfactant proteins, aquaporins and ENaC increases between 100 and 140 days of gestation in an ovine model. Further exploring these pathways and their hormonal regulation could highlight some new explanations in the pathophysiology of neonatal respiratory diseases

Genetic determinism of lipogenesis in the mammary gland of milking ruminants

National audienc

Extracellular vesicles from early pregnant uterine fluids trigger expression of implantation-related markers in ovine endometrium

Extracellular vesicles from early pregnant uterine fluids trigger expression of implantation-related markers in ovine endometrium. 3. Cellfit annual meeting 201

Analyse génétique de la lipogénèse dans le tissu mammaire des ruminants laitiers. Identification et caractérisation des facteurs génétiques contrôlant la variabilité du taux de matières grasses dans le lait de chèvre

AIP Lipogénèse. Rapport 96*INRA, Centre de Clermont-Theix (FRA) Diffusion du document : INRA, Centre de Clermont-Theix (FRA) "Chantier qualité spécifique "Auteurs Externes" département de Génétique animale : uniquement liaison auteur au référentiel HR-Access "National audienc

Extracellular vesicles from early pregnant uterine fluids promote expression of implantation-related markers in ovine endometrium

Theme: Early Development and PregnancyExtracellular vesicles (EVs) are crucial for intercellular communications and they may play important role in the delivery of molecular messages during the pre-implantation period of pregnancy. EVs have been isolated from uterine luminal fluid (ULF) in human and sheep. Recent data have provided evidence that EVs contained in ovine ULF can penetrate endometrial epithelial cells after a 6-days infusion in vivo. Nevertheless, embryo implantation involves rapid and dynamic changes in molecular interactions with the endometrium. Our present work aims to determine whether EVs collected from ULF interact with endometrial epithelial cells and modify cell physiology after a short time of in vitro and in vivo incubation conditions.Primary cultures of endometrial epithelial cells were derived from ovine uteri on day 12 post-oestrus. EVs were purified from ovine ULFs on Day 14 of pregnancy (2 days before conceptus implantation). The presence of EVs in ULF was confirmed by transmission electron microscopic observation. ULF EVs were labeled with lipophilic PKH26 fluorescent dye and then incubated with primary cultures of epithelial cells during 30 min to 24h. Confocal microscopy analyses revealed an uptake of EVs as early as 30 minutes after incubation, followed by a progressive increase of intracellular fluorescence up to 6 hours.For the in vivo study, ovine ULF EVs isolated on Day 14 of pregnancy were labeled with PKH26 fluorescent dye and infused into the uterine lumen of cyclic ewes on Day 12 post-oestrus. After 24h, numerous epithelial cells from the luminal layer and superficial glands exhibited an intensive fluorescence signal, whereas deep endometrial glands displayed few fluorescent cells. No signal was detectable in the stroma. The impact of EVs on endometrial function was investigated by quantifying transcript expression of a selection of endometrial genes. First data pointed out that expression of two genes, including the Myxovirus-Resistance Protein (MX1) was up-regulated following EVs uptake by the endometrial epithelium. This work provides first evidence that ovine EVs from pregnant ULF can (i) enter in endometrial epithelial cells within 30 min in vitro or 24h in vivo (ii) modulate expression of endometrial gene expression known to be critical for embryo implantation. These results suggest a critical role for EVs in the preparation of endometrium when implantation iniates

Implantation-related genes in the ovine endometrium are regulated by extracellular vesicles from earlypregnant uterine fluids

National audienc