Project description:To further study gene expression regulated by 17b-estradiol in uteri, we have employed whole gene microarray profiling to identify genes specifically regulated by this site of methylation of ERa (Arg260). Control littermates were used named WT.
Project description:We used microarrays to detail the global programme of gene expression in mammary luminal cells C451A-ERα and WT female mice treated by E2 0.01 MG and E2 0.01 MG +Pg 1.5 MG during 21 days.
Project description:Ovariectomized WT, KIKO (DNA-binding deficient ERα) or αERKO female mice were injected (ip) with saline (vehicle), estradiol (E2; 250 ng), bisphenol A (BPA; 750 µg) or 2,2-bis(p-hydroxyphenyl)-1,1,1-trichloroethane (HPTE; 750 µg) and uteri were collected after 2 or 24 hours. Uterine profiles were compared and indicated the early (2 hour) responses to E2 were highly correlated to the BPA and HPTE profiles. KIKO patterns included overlap with WT but also included distinct responses. Later (24 hour) responses in the KIKO were weaker, indicating DNA binding is needed to maintain the estrogenic response. BPA and HPTE also showed a weakened late response in the WT, suggesting they are impeded estrogens.
Project description:To further study gene expression regulated by 17b-estradiol in uteri, we have employed whole gene microarray profiling to identify genes specifically regulated by the Estrogen receptor ERα localized either at the plasma membrane or in the nucleus. Two mice models have been used, the mice named ERa-AF2° (named AF2_KO and on C57BL6/J background) in which 7 aminoacids have been deleted in the AF2 domain and the mice C451A-ERa (named MISS_KO and on C57BL6/N background) mutated for the C451 into Ala on ERa. Control littermates were used for each mutant mice respectively name AF2_WT or MISS_WT.
Project description:Background: Estrogen receptor (ERα) and aryl hydrocarbon receptor (AHR) are two nuclear receptors involved in regulating gene expression. ERα and AHR are regulated by estradiol(E2) and TCDD respectively. They are also regulated by dietary ligands including 3,3´diindolylmethane (DIM) and resveratrol (RES). DIM is an ERα and AHR agonist, while RES is an ERα agonist and AHR antagonist. Few studies have investigated the impact of RES and DIM on ERα and AHR signaling at a genome-wide level. This study assessed ERα and AHR binding and associated gene expression changes after treatment of MCF-7 human breast cancer cells with DIM, RES, E2, TCDD, and E2+TCDD for 1 hour and 6 hours before ChIP and RNA sequencing respectively. Results: 88% and 86% of the ERα bound sites after RES and DIM overlapped with E2 ERα sites. RES and DIM resulted in 577 and 446 differentially expressed genes (DEGs) respectively compared to 866 after E2. 68% and 62.3% of the DEGs after RES and DIM were closest to an ERα binding site. Motif analysis indicated enrichment for AHRE motif among DIM ERα sites but not among E2 or RES ERα sites. Both DIM and E2+TCDD resulted in greater genome wide binding of AHR than TCDD. DIM and E2+TCDD resulted in 10546 and 8904 AHR and ERα co-occupied sites respectively. While co-occupied sites for both enriched for the AHR and ERE motif among others, DIM mediated co-occupied sites enriched for Tcfcp2l1, Tgif1, Gata3 motifs while E2+TCDD mediated ones enriched for the NF1 and Ppara motifs. Overlap of coregulated DEGs after DIM and E2+TCDD indicated 123 were the same among both with 81 and 85 unique coregulated DEGs respectively. Enrichment analysis indicated that more enrichment terms were different than similar for coregulated genes after E2+TCDD and DIM. Conclusions: AHR activation is responsible for DIM mediated reduced regulation of gene expression by ERα relative to E2 and only a subset of the DEG’s after DIM and RES are ERα targets indicating future studies into other transcription factors regulated by DIM and RES are needed for insights into the regulation of gene expression by these ligands.
Project description:Pre-pubertal (21 days old) WT or ERa knockout we compared RNA from 21-day old WT and Ex3aERKO uteri that were treated with saline vehicle (V) estradiol (E2) or IGF1 for 2 hours or 24 hours
Project description:17ß-Estradiol (E2) is well known to be associated with uterine cancer, endometriosis, and leiomyomas. Although insulin-like growth factor I (IGF-I) has been identified as a mediator of the uterotrophic effect of E2 in several studies, this mechanism is still not well understood. In the present study, identification of the genes modulated by a physiological dose of E2, in the uterus, has been done in ovariectomized mice using Affymetrix microarrays. The E2-induced genomic profile shows that multiple genes belonging to the IGF-I pathway are affected after exposure to E2. Two phases of regulation could be identified. First, from 0 to 6 h, the expression of genes involved in the cell cycle, growth factors, protein tyrosine phosphatases, and MAPK phosphatases is quickly upregulated by E2, while IGF-I receptor and several genes of the MAPK and phosphatidylinositol 3-kinase pathways are downregulated. Later, i.e., from 6 to 24 h, transporters and peptidases/proteases are stimulated, whereas defense-related genes are differentially regulated by E2. Finally, cytoarchitectural genes are modulated later. The present data show that a physiological dose of E2 induces, within 24 h, a series of transcriptional events that promote the uterotrophic effect. Among these, the E2-mediated activation of the IGF-I pathway seems to play a pivotal role in the uterotrophic effect. Furthermore, the protein tyrosine phosphatases and MAPK phosphatases are likely to modulate the estrogenic uterotrophic action by targeting, at different steps, the IGF-I pathway. Keywords: E2 time course