A Role for Nuclear Factor Interleukin-3 (NFIL3), a Critical Transcriptional Repressor, in Down-Regulation of Periovulatory Gene Expression

College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, People's Republic of China.
Molecular Endocrinology (Impact Factor: 4.02). 03/2011; 25(3):445-59. DOI: 10.1210/me.2010-0250
Source: PubMed


The LH surge triggers dramatic transcriptional changes in genes associated with ovulation and luteinization. The present study investigated the spatiotemporal expression of nuclear factor IL-3 (NFIL3), a transcriptional regulator of the basic leucine zipper transcription factor superfamily, and its potential role in the ovary during the periovulatory period. Immature female rats were injected with pregnant mare's serum gonadotropin, treated with human chorionic gonadotropin (hCG), and ovaries or granulosa cells were collected at various times after hCG. Nfil3 mRNA was highly induced both in intact ovaries and granulosa cells after hCG treatment. In situ hybridization demonstrated that Nfil3 mRNA was highly induced in theca-interstitial cells at 4-8 h after hCG, localized to granulosa cells at 12 h, and decreased at 24 h. Overexpression of NFIL3 in granulosa cells inhibited the induction of prostaglandin-endoperoxide synthase 2 (Ptgs2), progesterone receptor (Pgr), epiregulin (Ereg), and amphiregulin (Areg) and down-regulated levels of prostaglandin E2. The inhibitory effect on Ptgs2 induction was reversed by NFIL3 small interfering RNA treatment. In theca-interstitial cells the expression of hydroxyprostaglandin dehydrogenase 15-(nicotinamide adenine dinucleotide) (Hpgd) was also inhibited by NFIL3 overexpression. Data from luciferase assays demonstrated that NFIL3 overexpression decreased the induction of the Ptgs2 and Areg promoter activity. EMSA and chromatin immunoprecipitation analyses indicated that NFIL3 binds to the promoter region containing the DNA-binding sites of cAMP response element binding protein and CCAAT enhancer binding protein-β. In summary, hCG induction of NFIL3 expression may modulate the process of ovulation and theca-interstitial and granulosa cell differentiation by regulating expression of PTGS2, PGR, AREG, EREG, and HPGD, potentially through interactions with cAMP response element binding protein and CCAAT enhancer binding protein-β on their target gene promoters.

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    • "After washing with PBS, cells were digested with trypsin and then collected by centrifugation at 1200 × g for 2 min. As described previously, cells were briefly resuspended in Annexin V-binding buffer and incubated with FITC-labeled Annexin V and PI for 15 min at room temperature in the dark [28] [29] [30]. Afterward , the samples were immediately analyzed by flow cytometry. "
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    ABSTRACT: Benomyl and carbendazim are benzimidazole fungicides that are used throughout the world against a wide range of fungal diseases of agricultural products. There is as yet little information regarding the toxicity of benzimidazole fungicides to human placenta. In this study, we utilized human placental trophoblast cell line HTR-8/SVneo (HTR-8) to access the toxic effects of benomyl and carbendazim. Our data showed that these two fungicides decreased cell viability and the percentages of cells in G0/G1 phase, as well as induced apoptosis of HTR-8 cells. The invasion and migration of HTR-8 cells were significantly inhibited by benomyl and carbendazim. We further found that benomyl and carbendazim altered the expression of protease systems (MMPs/TIPMs and uPA/PAI-1) and adhesion molecules (integrin α5 and β1) in HTR-8 cells. Our present study firstly shows the deleterious effects of benomyl and carbendazim on placental cells and suggests a potential risk of benzimidazole fungicides to human reproduction. Copyright © 2014. Published by Elsevier Inc.
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    • "For in vitro studies, animals were scarified at 48 h after PMSG administration and ovaries were collected to isolate and culture granulosa cells as described previously [29]; [30]. Cells were cultured in HyQ MEM-RS (ThermoFisher Scientific, Waltham, MA, USA) media supplemented with 0.05 mg/ml gentamicin and 1× insulin, transferrin, and selenium, as well as with 1 I U/ml hCG to mimic LH action that induces ovarian gene expression and prostaglandins production in vitro [32]; [33]. Cells were exposed to o,p’-DDT at concentration of 10−12 to 10−8 M for 6 h. "
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    • "The AdEasy XL adenoviral vector system kit (Stratagene) was used to construct Plk2 and Plk3 recombinant adenovirus. The processes for generating and propagating recombinant adenoviruses were described previously [17]. Briefly, the full length of rat Plk2 and Plk3 genes were cloned into the pShuttle-CMV vector and then a recombinant Ad-Plk2 and Ad-Plk3 plasmids were generated by homologous recombination. "
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    ABSTRACT: The highly conserved polo-like kinases (Plks) are potent regulators of multiple functions in the cell cycle before and during mitotic cell division. We investigated the expression pattern of Plk genes and their potential role(s) in the rat ovary during the periovulatory period. Plk2 and Plk3 were highly induced both in intact ovaries and granulosa cells in vivo after treatment with the luteinizing hormone (LH) agonist, human chorionic gonadotropin (hCG). In vitro, hCG stimulated the expression of Plk2 in granulosa cells, but not Plk3. This induction of Plk2 expression was mimicked by both forskolin and phorbol 12 myristate 13-acetate (PMA). Moreover, Plk2 expression was reduced by inhibitors of prostaglandin synthesis or the EGF pathway, but not by progesterone receptor antagonist (RU486) treatment. At the promoter level, mutation of the Sp1 binding sequence abolished the transcriptional activity of the Plk2 gene. ChIP assays also revealed the interaction of endogenous Sp1 protein in the Plk2 promoter region. Functionally, the over-expression of Plk2 and Plk3 arrested granulosa cells at the G0/G1 phase of the cell cycle. In contrast, the knockdown of Plk2 expression in granulosa cells decreased the number of cells in the G0/G1 stage of the cell cycle, but increased granulosa cell viability. In summary, hCG induced Plk2 and Plk3 expression in the rat ovary. Prostaglandins and the EGF signaling pathway are involved in regulating Plk2 expression. The transcription factor Sp1 is important for Plk2 transcriptional up-regulation. Our findings suggest that the increase in Plk2 and Plk3 expression contributes to the cell cycle arrest of granulosa cells which is important for the luteinization of granulosa cells during the periovulatory period.
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