Project description:Purpose: The goal of this study is to analyze the Cryptochrome-Cop1 axis in mammals Methods: mouse embryonic fibroblasts treated with dexamethasone, KL001 and/or Cop1 knockdown. Results: The transcriptomic analysis helps us to support our finding that the Cryptochromes-dependent repression of the glucocorticoid receptor is mediated by Cop1.
Project description:PURPOSE: To provide a detailed gene expression profile of the normal postnatal mouse cornea. METHODS: Serial analysis of gene expression (SAGE) was performed on postnatal day (PN)9 and adult mouse (6 week) total corneas. The expression of selected genes was analyzed by in situ hybridization. RESULTS: A total of 64,272 PN9 and 62,206 adult tags were sequenced. Mouse corneal transcriptomes are composed of at least 19,544 and 18,509 unique mRNAs, respectively. One third of the unique tags were expressed at both stages, whereas a third was identified exclusively in PN9 or adult corneas. Three hundred thirty-four PN9 and 339 adult tags were enriched more than fivefold over other published nonocular libraries. Abundant transcripts were associated with metabolic functions, redox activities, and barrier integrity. Three members of the Ly-6/uPAR family whose functions are unknown in the cornea constitute more than 1% of the total mRNA. Aquaporin 5, epithelial membrane protein and glutathione-S-transferase (GST) omega-1, and GST alpha-4 mRNAs were preferentially expressed in distinct corneal epithelial layers, providing new markers for stratification. More than 200 tags were differentially expressed, of which 25 mediate transcription. CONCLUSIONS: In addition to providing a detailed profile of expressed genes in the PN9 and mature mouse cornea, the present SAGE data demonstrate dynamic changes in gene expression after eye opening and provide new probes for exploring corneal epithelial cell stratification, development, and function and for exploring the intricate relationship between programmed and environmentally induced gene expression in the cornea. Keywords: other
Project description:The circadian transcriptional repressors cryptochromes 1 (Cry1) and 2 (Cry2) interact with the C-terminus of the glucocorticoid receptor (GR) and are required for transrepression in response to the synthetic GR ligand dexamethasone (Dex) in mouse embryonic fibroblasts. Dex induction of many genes was increased in Cry-deficient fibroblasts suggesting that cryptochromes oppose transactivation in addition to contributing to transrepression. In mice, genetic loss of Cry1 and/or Cry2 resulted in glucose intolerance and constitutively high levels of circulating corticosterone, suggesting reduced glucocorticoid suppression of the hypothalamic-pituitary-adrenal axis coupled with increased sensitivity to the hyperglycemic effects of glucocorticoid-mediated transactivation in the liver. Cry1 and Cry2 association with a GRE in the Pck1 promoter was stimulated by Dex, and Dex-induced transcription of pck1 was strikingly increased in Cry-deficient livers. Finally, cry1-/-;cry2-/- mice subjected to 8 weeks of chronic Dex treatment exhibited incomplete suppression of circulating corticosterone and greater glucose intolerance compared with wildtype littermates subjected to the same chronic treatment, consistent with enhanced transcriptional response to the synthetic glucocorticoid ligand. Total RNA was obtained from WT and Cry1/2 KO MEFs treated with Dexamethasone (1uM) or control EtOH for 16 hours.
