Project description:Estrogen Receptor alpha (ERα) is a key driver of most breast cancers, and it is the target of endocrine therapies used in the clinic to treat women with ERα positive (ER+) breast cancer. The two methods ChIP-seq (chromatin immunoprecipitation coupled with deep sequencing) and RIME (Rapid Immunoprecipitation of Endogenous Proteins) have greatly improved our understanding of ERα function during breast cancer progression and in response to anti-estrogens. A critical component of both ChIP-seq and RIME protocols is the antibody that is used to pull down the bait protein. To date, most of the ChIP-seq and RIME experiments for the study of ERα have been performed using the sc-543 antibody from Santa Cruz Biotechnology. However, this antibody has been discontinued, thereby severely impacting the study of ERα in normal physiology as well as diseases such as breast cancer and ovarian cancer. Here, we compare the sc-543 antibody with other commercially available antibodies, and we show that 06-935 (EMD Millipore) and ab3575 (Abcam) antibodies can successfully replace the sc-543 antibody for ChIP-seq and RIME experiments.
Project description:Fetal life is a crucial period for sexual reproduction when bipotential gonads differentiate into either a testis or an ovary. Gaining insights into the complex molecular events underlying this process is central to a better understanding of disorders of sexual development. The present work therefore intends to improve the knowledge on molecular pathways at play during gonad development in humans using RNA-Sequencing.
Project description:Sex determination in mammals hinges on a cell fate decision in the fetal bipotential gonad between male Sertoli cells and female granulosa cells. While this decision normally is permanent, loss of key cell fate regulators such as the transcription factors Dmrt1 and Foxl2 can cause postnatal transdifferentiation from Sertoli to granulosa-like or vice versa. Here we examine the mechanism of transdifferentiation in mice carrying either a null mutation of Dmrt1 or a point mutation, R111G, that alters the DNA binding motif and causes human XY gonadal dysgenesis and sex reversal. We first define genes misexpressed during transdifferentiation and then show that female transcriptional regulators driving transdifferentiation in the mutant XY gonad (ESR2, LRH1, FOXL2) bind chromatin sites related to those normally bound in the XX ovary. We then define gene expression changes at the onset of transdifferentiation and abnormal chromatin compartments that may help destabilize cell fate and initiate transdifferentiation. We model the R111G mutation in mice and show that it causes dominant gonadal dysgenesis, analogous to its human phenotype but less severe. We show that R111G partially feminizes the testicular transcriptome and causes dominant disruption of DMRT1 binding specificity in vivo. These data help illuminate how transdifferentiation occurs when sexual cell fate maintenance is disrupted and identify chromatin sites and transcripts that may play key roles in the transdifferentiation process.
Project description:Activation of JAK-STAT3 signaling by leukemia inhibitory factor (LIF) is required for maintaining self-renewal of mouse embryonic stem cells (mESCs). STAT3 perform cell type-specific roles in different cell type, here we revisit the role of STAT3 using mouse female germ stem cell (mFGSCs). We applied CRISPR/Cas9 system to generate Stat3 knockout FGSCs and then observed cell growth inhibition and cell cycle arrest in KO cell line. By combining genome wide ChIP-Seq and RNA-Seq, we identified 5990 STAT3 binding sites and discovered serval genes specific regulated by STAT3 that were involved in stem cell proliferation and female gonad development in FGSCs. In general, we identify key roles of STAT3 for sustains self-renewal and proliferation for FGSCs in this study.
Project description:Morphogenesis of the gonad requires cell-cell adhesion changes between diverse cell types. In the Drosophila gonad, the gene traffic jam regulates cell adhesion changes required for gonad formation and germ cell development (Li et al., 2003. Nature Cell Biol). To determine if the mammalian homologs of traffic jam in mammals, c-Maf and Mafb, also play a role in the transcription regulation of cell adhesion molecules in the mouse gonad, we performed a microarray analysis of FACS-purified Mafb-GFP-positive cells in E12.5 male control and c-Maf/Mafb mutant gonads. We used microarrays to determine genes affected by c-Maf mutation in E12.5 mouse gonad/mesonephros interstitial cells and macrophages