Project description:Beyond demonstrating a critical role for progesterone receptor signaling in normal mammary epithelial proliferation, the progesterone receptor knockout mouse disclosed the progesterone receptor along with its effector pathways as key determinants of mammary neoplastic progression. Despite these advances, however, further progress in our mechanistic understanding of progesteroneâ??s involvement in mammary morphogenesis and tumorigenesis is contingent upon defining the essential effector pathways responsible for transducing the progesterone signal into a mammary proliferative and/or pro-survival response. Toward this goal, a judiciously chosen acute progesterone treatment regimen together with microarray methods was applied to the mammary gland of the normal mouse to uncover new effectors that operate immediately downstream of the progesterone mammary signal. Examination of the resultant progesterone-responsive transcriptome disclosed â??inhibitor of differentiation or DNA binding 4â?? (Id4) as a molecular target acutely induced by progesterone in the murine mammary epithelium. Experiment Overall Design: Microarray analysis was performed on mammary tissue total RNA obtained from ovariectomized mice previously treated with progesterone for 4, 16, 28, and 76 hours. For each hormone treatment time-point, mammary gland microarray data from sesame oil (vehicle) treated mice was included as controls. Total mammary gland RNA from each time-point and treatment group was interrogated using the Affymetrix GeneChip Mouse Genome 430 2.0 Array. For a given time-point and treatment group, three sets of mice (5 mice in each set) were used for gene expression profiling; mammary RNA pooled from each set was hybridized to one microarray chip. Therefore, a total of 15 mice (or 3 microarray chips) were used per time-point and treatment group.
Project description:Progesterone (P) acting through its cognate nuclear receptors (PRs) plays an essential role in driving pregnancy-associated branching morphogenesis of the mammary gland. However, the fundamental mechanisms, including global cistromic and acute genomic transcriptional responses that are required to elicit active branching morphogenesis in response to P, have not been elucidated. We used chromatin immunoprecipitation followed by deep sequencing (ChIP-seq) to identify P-regulated genes that directly recruit PRs in the mouse mammary gland after acute P treatment. Two replicate PR ChIP samples and two replicate input DNA control samples from mouse mammary glands after mice are treated subcutaneously with 17?-Estradiol for 24 hours and then 17?-Estradiol plus Progesterone for 6 hours.
Project description:Estrogen Receptor is a key transcriptional regulator in mammary gland development and breast cancer. In this study, we have mapped the Estrogen Receptor chromatin binding patterns in healthy mouse mammary gland A minimum of 6 pairs of mouse mammary gland pads from mice at 5-6 weeks of age were excised and Estrogen Receptor ChIp-seq was performed.
Project description:Beyond demonstrating a critical role for progesterone receptor signaling in normal mammary epithelial proliferation, the progesterone receptor knockout mouse disclosed the progesterone receptor along with its effector pathways as key determinants of mammary neoplastic progression. Despite these advances, however, further progress in our mechanistic understanding of progesterone’s involvement in mammary morphogenesis and tumorigenesis is contingent upon defining the essential effector pathways responsible for transducing the progesterone signal into a mammary proliferative and/or pro-survival response. Toward this goal, a judiciously chosen acute progesterone treatment regimen together with microarray methods was applied to the mammary gland of the normal mouse to uncover new effectors that operate immediately downstream of the progesterone mammary signal. Examination of the resultant progesterone-responsive transcriptome disclosed “inhibitor of differentiation or DNA binding 4” (Id4) as a molecular target acutely induced by progesterone in the murine mammary epithelium. Keywords: time course
Project description:Progesterone (P) acting through its cognate nuclear receptors (PRs) plays an essential role in driving pregnancy-associated branching morphogenesis of the mammary gland. However, the fundamental mechanisms, including global cistromic and acute genomic transcriptional responses that are required to elicit active branching morphogenesis in response to P, have not been elucidated. We used microarray analysis to identify global gene expression signatures that are acutely regulated by PRs in the mouse mammary gland after acute P treatment. Mammary gland gene expression data from 10-week-old ovariectomized wildtype and progesterone receptor null mice treated subcutaneously with 17β-Estradiol for 24 hours and then 17β-Estradiol plus Progesterone for 8 or 24 hours. Three replicate pools were tested with three mice per pool.