Project description:The Otx2 homeobox transcription factor is essential for gastrulation and early neural development. We generated Otx2 conditional knockout (cKO) mice to investigate its roles in telencephalon development after E9.0. We conducted transcriptional profiling and in situ hybridization to identify genes de-regulated in Otx2 cKO ventral forebrain. In parallel, we used ChIP-seq to identify enhancer elements, OTX2 binding motif, and which de-regulated genes are likely direct targets of Otx2 transcriptional regulation. We found that Otx2 was essential in septum specification; regulation of Fgf signaling in the rostral telencephalon; and medial ganglionic eminence (MGE) patterning, neurogenesis, and oligodendrogenesis. Within the MGE, Otx2 was required for ventral but not dorsal identity; this is the first demonstration of a transcription factor that contributes to regional patterning within the MGE. Microdissected subpallium (septum, MGE, and LGE ) from wildtype E12.5 CD-1 embryos was used in three independentanti-OTX2 ChIP-seq experiments.
Project description:The Otx2 homeobox transcription factor is essential for gastrulation and early neural development. We generated Otx2 conditional knockout (cKO) mice to investigate its roles in telencephalon development after E9.0. We conducted transcriptional profiling and in situ hybridization to identify genes de-regulated in Otx2 cKO ventral forebrain. In parallel, we used ChIP-seq to identify enhancer elements, OTX2 binding motif, and which de-regulated genes are likely direct targets of Otx2 transcriptional regulation. We found that Otx2 was essential in septum specification; regulation of Fgf signaling in the rostral telencephalon; and medial ganglionic eminence (MGE) patterning, neurogenesis, and oligodendrogenesis. Within the MGE, Otx2 was required for ventral but not dorsal identity; this is the first demonstration of a transcription factor that contributes to regional patterning within the MGE.
Project description:The Otx2 homeobox transcription factor is essential for gastrulation and early neural development. We generated Otx2 conditional knockout (cKO) mice to investigate its roles in telencephalon development after E9.0. We conducted transcriptional profiling and in situ hybridization to identify genes de-regulated in Otx2 cKO ventral forebrain. In parallel, we used ChIP-seq to identify enhancer elements, OTX2 binding motif, and which de-regulated genes are likely direct targets of Otx2 transcriptional regulation. We found that Otx2 was essential in septum specification; regulation of Fgf signaling in the rostral telencephalon; and medial ganglionic eminence (MGE) patterning, neurogenesis, and oligodendrogenesis. Within the MGE, Otx2 was required for ventral but not dorsal identity; this is the first demonstration of a transcription factor that contributes to regional patterning within the MGE.
Project description:The embryonic basal ganglia generates multiple projection neurons and interneuron subtypes from distinct progenitor domains. Combinatorial interactions of transcription factors (TFs), regulatory elements (REs), and chromatin are thought to precisely regulate gene expression. In the medial ganglionic eminence (MGE), the NKX2-1 TF controls regional identity and, with LHX6, is necessary to specify pallidal projection neurons and forebrain interneurons. We dissected the molecular functions of NKX2-1 by defining its chromosomal binding regions, regulation of gene expression and epigenetic state. NKX2-1 binding at distal REs led to a repressed epigenetic state and transcriptional repression in the ventricular zone. Conversely, Nkx2-1 is required to establish a permissive chromatin state and transcriptional activation in the sub- ventricular and mantle zones. Moreover, combinatorial binding of NKX2-1 and LHX6 promotes transcriptionally permissive chromatin and activates genes expressed in cortical migrating interneurons. Our integrated approach provides a foundation for elucidating transcriptional networks guiding the development of the MGE and its descendants.
Project description:The embryonic basal ganglia generates multiple projection neurons and interneuron subtypes from distinct progenitor domains. Combinatorial interactions of transcription factors (TFs), regulatory elements (REs), and chromatin are thought to precisely regulate gene expression. In the medial ganglionic eminence (MGE), the NKX2-1 TF controls regional identity and, with LHX6, is necessary to specify pallidal projection neurons and forebrain interneurons. We dissected the molecular functions of NKX2-1 by defining its chromosomal binding regions, regulation of gene expression and epigenetic state. NKX2-1 binding at distal REs led to a repressed epigenetic state and transcriptional repression in the ventricular zone. Conversely, Nkx2-1 is required to establish a permissive chromatin state and transcriptional activation in the sub- ventricular and mantle zones. Moreover, combinatorial binding of NKX2-1 and LHX6 promotes transcriptionally permissive chromatin and activates genes expressed in cortical migrating interneurons. Our integrated approach provides a foundation for elucidating transcriptional networks guiding the development of the MGE and its descendants.
Project description:The choice between somatic and germline fates is essential for species survival. This choice occurs in embryonic epiblast cells, as these cells are competent for both somatic and germline differentiation. Transcription factors (TFs) play a central role in this process by binding to specific chromatin loci to modulate gene expression and determine cell identity. The TF OTX2 regulates the choice between somatic and germline fates, as Otx2-null epiblast-like cells (EpiLCs) form primordial germ cell-like cells (PGCLCs) with enhanced efficiency. However, the mechanisms by which OTX2 achieves this function are not fully characterized. Here we show that OTX2 controls chromatin accessibility to enable somatic differentiation. By performing CUT&RUN for OTX2 and ATAC-seq in wild-type and Otx2-null embryonic stem cells and EpiLCs, we identified regions where OTX2 binding opens chromatin. Enforced OTX2 expression maintains accessibility at these regions and induces opening of 4,000 additional somatic-associated regions in the presence of PGC-inducing cytokines. Once cells have acquired germline identity, the 4,000 additional somatic associated regions do not respond to OTX2 and remain closed. Our results indicate that OTX2 works in cells with dual competence for both somatic and germline differentiation to increase accessibility of somatic regulatory regions and induce the somatic fate at the expense of the germline.
Project description:The choice between somatic and germline fates is essential for species survival. This choice occurs in embryonic epiblast cells, as these cells are competent for both somatic and germline differentiation. Transcription factors (TFs) play a central role in this process by binding to specific chromatin loci to modulate gene expression and determine cell identity. The TF OTX2 regulates the choice between somatic and germline fates, as Otx2-null epiblast-like cells (EpiLCs) form primordial germ cell-like cells (PGCLCs) with enhanced efficiency. However, the mechanisms by which OTX2 achieves this function are not fully characterized. Here we show that OTX2 controls chromatin accessibility to enable somatic differentiation. By performing CUT&RUN for OTX2 and ATAC-seq in wild-type and Otx2-null embryonic stem cells and EpiLCs, we identified regions where OTX2 binding opens chromatin. Enforced OTX2 expression maintains accessibility at these regions and induces opening of 4,000 additional somatic-associated regions in the presence of PGC-inducing cytokines. Once cells have acquired germline identity, the 4,000 additional somatic associated regions do not respond to OTX2 and remain closed. Our results indicate that OTX2 works in cells with dual competence for both somatic and germline differentiation to increase accessibility of somatic regulatory regions and induce the somatic fate at the expense of the germline.