Project description:Branching morphogenesis of the mammary gland is driven by the highly motile terminal end bud (TEB) throughout pubertal development. The stem cell enriched, proliferative TEB branches as it invades the mammary fat pad to create a complex network of ducts. The gene expression programs specific to the TEB and the differentiated duct are poorly understood. We conducted a time course analysis of gene expression in the TEB and duct throughout branching morphogenesis. Additionally, we determined the gene regulatory networks coordinated by the Co-factor of LIM domains (CLIM/LDB) transcriptional regulators and determined an essential function for CLIMs in branching morphogenesis by maintaining basal mammary epithelial stem cells and promoting cell proliferation. We used laser capture microdissection to isolate TEB and duct cells throughout branching morphogenesis. We then profiled gene expression in these cells to determine gene regulatory networks involved in branching morphogenesis, and specifically those regulated by CLIM transcriptional regulators.
Project description:Branching morphogenesis of the mammary gland is driven by the highly motile terminal end bud (TEB) throughout pubertal development. The stem cell enriched, proliferative TEB branches as it invades the mammary fat pad to create a complex network of ducts. The gene expression programs specific to the TEB and the differentiated duct are poorly understood. We conducted a time course analysis of gene expression in the TEB and duct throughout branching morphogenesis. Additionally, we determined the gene regulatory networks coordinated by the Co-factor of LIM domains (CLIM/LDB) transcriptional regulators and determined an essential function for CLIMs in branching morphogenesis by maintaining basal mammary epithelial stem cells and promoting cell proliferation. We used laser capture microdissection to isolate TEB and duct cells throughout branching morphogenesis. We then profiled gene expression in these cells to determine gene regulatory networks involved in branching morphogenesis, and specifically those regulated by CLIM transcriptional regulators. Mouse mammary glands from 4, 6, 8, and 10 week old mice (early puberty through early adulthood) were used for laser capture microdissection of TEB and duct cells from WT and K14-DN-Clim transgenic mice. RNA was isolated (Qiagen) and hybridized to Affymetrix MouseGene 1.0 ST arrays. In addition, basal (CD29HiCD24+Lin-) and Luminal (CD29LoCD24+Lin-) cells were sorted and RNA collected for hybridization to Affymetrix MouseGene 1.0ST arrays.
Project description:Mammary gland branching morphogenesis is thought to relie on the mobilization of the membrane-anchored matrix metalloproteinase, Mmp14/MT1-MMP, to drive mammary epithelial invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that this proteinase plays during postnatal mammary gland development in vivo remain undefined. A mammary gland branching program that occurs during the first 4 weeks of postnatal mouse development, in tandem with recently developed Mmp14-floxed mice and MMTV-Cre transgenics that express Cre recombinase throughout the mammary epithelial cell compartment, were used to characterize the impact of deleting epithelial cell Mmp14 on mammary gland morphogenesis. Transcriptome profiling of mammary epithelial cells was used to investigate the effects of MMTV-Cre expression on the postnatal mammary epithelial cell compartment in an unbiased fashion
Project description:Mammary gland branching morphogenesis is thought to relie on the mobilization of the membrane-anchored matrix metalloproteinase, Mmp14/MT1-MMP, to drive mammary epithelial invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that this proteinase plays during postnatal mammary gland development in vivo remain undefined. A mammary gland branching program that occurs during the first 4 weeks of postnatal mouse development, in tandem with recently developed Mmp14-floxed mice and MMTV-Cre transgenics that express Cre recombinase throughout the mammary epithelial cell compartment, were used to characterize the impact of deleting epithelial cell Mmp14 on mammary gland morphogenesis. Transcriptome profiling of mammary epithelial cells was used to investigate the functional roles of MT1-MMP in the postnatal mammary epithelial cell compartment in an unbiased fashion
Project description:Mammary gland branching morphogenesis is thought to depend on the mobilization of proteolytic machinery from the matrix metalloproteinase (MMP) family, namely MT1-MMP/MMP14, to drive coordinated epithelial cell invasion through the interstitial extracellular matrix, but the dominant effector has remained undefined. Unexpectedly, we find MMP14 controls postnatal mammary gland branching from the periductal stroma. Transcriptome profiling of stromal cell-targeted mammary glands was used to characterize the impact of stromal Mmp14-targeting on the growth factor and signaling cascades implicated in mammary gland morphogenesis. Transcriptome profiling of ductal networks and associated stroma was used to investigate the functional roles of MMP14 in the postnatal mammary gland stroma in an unbiased fashion.
Project description:Mammary gland branching morphogenesis is thought to depend on the mobilization of the membrane-anchored matrix metalloproteinases, MT1-MMP and MT2-MMP, that drive epithelial cell invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that these proteinases play during mammary gland development in vivo remains undefined. A mammary gland branching program that occurs during the first 10 days of early postnatal development was used to characterize the impact of global Mt1-mmp or Mt2-mmp targeting on mammary gland morphogenesis. Transcriptome profiling of ductal networks and associated stroma was used to investigate the functional roles of MT2-MMP in the early postnatal mammary gland in an unbiased fashion.
Project description:Mammary gland branching morphogenesis is thought to depend on the mobilization of the membrane-anchored matrix metalloproteinases, MT1-MMP and MT2-MMP, that drive epithelial cell invasion by remodeling the extracellular matrix and triggering associated signaling cascades. However, the roles that these proteinases play during mammary gland development in vivo remains undefined. A mammary gland branching program that occurs during the first 10 days of early postnatal development was used to characterize the impact of global Mt1-mmp or Mt2-mmp targeting on mammary gland morphogenesis. Transcriptome profiling of ductal networks and associated stroma was used to investigate the functional roles of MT1-MMP in the early postnatal mammary gland in an unbiased fashion.
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: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.
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.