Project description:Nkx2.2, Nkx6.1, and Olig2 repressors were overexpressed, singly or in combination, in in vitro-derived mouse neural progenitors to identify thier repression targets Overexpression study to identify genes repressed by Nkx2.2, Nkx6.1, and Olig2 in neural progenitors
Project description:Nkx2.2, Nkx6.1, and Olig2 repressors were overexpressed, singly or in combination, in in vitro-derived mouse neural progenitors to identify thier repression targets
Project description:Nkx2.2, Nkx6.1, and Olig2 are transcriptional repressors regulating somatic motor neuron and interneuron subtypes in neural progenitors. The purpose of this study was to identify their target genes and to elucidate their gene regulatory mechanisms, including their relationship to Sonic Hedgehog/Gli pathway.
Project description:During development neural stem cells (NSCs) in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Shh signaling promotes cortical RGCs to switch lineage to generate cortical oligodendrocytes and OB interneurons. During this lineage switch, cortical RGCs generate intermediate progenitor cells (IPCs) that express Ascl1, Egfr and Olig2, genes critically regulating gliogenesis. The timing of increased Ascl1 expression and the appearance of Egfr+ and Olig2+ cortical progenitors is concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes Olig2 expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Further, the transcriptional regulation of Olig2 and Egfr has not been explored. Here we show that in cortical progenitor cells, multiple genetic programs, including Pax6 and Gli3, prevent precocious expression of Olig2, a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple distal enhancers that control Olig2 expression in cortical progenitors and show that the mechanisms for regulating Olig2 expression are conserved between mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.
Project description:During development neural stem cells (NSCs) in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Shh signaling promotes cortical RGCs to switch lineage to generate cortical oligodendrocytes and OB interneurons. During this lineage switch, cortical RGCs generate intermediate progenitor cells (IPCs) that express Ascl1, Egfr and Olig2, genes critically regulating gliogenesis. The timing of increased Ascl1 expression and the appearance of Egfr+ and Olig2+ cortical progenitors is concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes Olig2 expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Further, the transcriptional regulation of Olig2 and Egfr has not been explored. Here we show that in cortical progenitor cells, multiple genetic programs, including Pax6 and Gli3, prevent precocious expression of Olig2, a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple distal enhancers that control Olig2 expression in cortical progenitors and show that the mechanisms for regulating Olig2 expression are conserved between mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.
Project description:During development neural stem cells (NSCs) in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Shh signaling promotes cortical RGCs to switch lineage to generate cortical oligodendrocytes and OB interneurons. During this lineage switch, cortical RGCs generate intermediate progenitor cells (IPCs) that express Ascl1, Egfr and Olig2, genes critically regulating gliogenesis. The timing of increased Ascl1 expression and the appearance of Egfr+ and Olig2+ cortical progenitors is concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes Olig2 expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Further, the transcriptional regulation of Olig2 and Egfr has not been explored. Here we show that in cortical progenitor cells, multiple genetic programs, including Pax6 and Gli3, prevent precocious expression of Olig2, a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple distal enhancers that control Olig2 expression in cortical progenitors and show that the mechanisms for regulating Olig2 expression are conserved between mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.
Project description:During development neural stem cells (NSCs) in the cerebral cortex, also known as radial glial cells (RGCs), generate excitatory neurons, followed by production of cortical macroglia and inhibitory neurons that migrate to the olfactory bulb (OB). Understanding the mechanisms for this lineage switch is fundamental for unraveling how proper numbers of diverse neuronal and glial cell types are controlled. We and others recently showed that Shh signaling promotes cortical RGCs to switch lineage to generate cortical oligodendrocytes and OB interneurons. During this lineage switch, cortical RGCs generate intermediate progenitor cells (IPCs) that express Ascl1, Egfr and Olig2, genes critically regulating gliogenesis. The timing of increased Ascl1 expression and the appearance of Egfr+ and Olig2+ cortical progenitors is concurrent with the switch from excitatory neurogenesis to gliogenesis and OB interneuron neurogenesis in the cortex. While Shh signaling promotes Olig2 expression in the developing spinal cord, the exact mechanism for this transcriptional regulation is not known. Further, the transcriptional regulation of Olig2 and Egfr has not been explored. Here we show that in cortical progenitor cells, multiple genetic programs, including Pax6 and Gli3, prevent precocious expression of Olig2, a gene essential for production of cortical oligodendrocytes and astrocytes. We identify multiple distal enhancers that control Olig2 expression in cortical progenitors and show that the mechanisms for regulating Olig2 expression are conserved between mouse and human. Our study reveals evolutionarily conserved regulatory logic controlling the lineage switch of cortical neural stem cells.
Project description:Down syndrome (DS), caused by triplication of human chromosome 21 (HSA21), is the most common genetic origin of intellectual disability. Despite the limited success of current pharmacological interventions, little has been achieved to reverse the abnormal brain developmental in DS. Here, using human induced pluripotent stem cell (hiPSC)-based brain organoid and in vivo human neuronal chimeric mouse brain models, we demonstrate that the HSA21 genes OLIG1 and OLIG2 exhibit distinct temporal expression patterns during neuronal differentiation. The population of OLIG2-expressing ventral forebrain neural progenitors is overabundant in DS, which results in excessive production of calretinin- and somatostatin-expressing GABAergic interneurons and causes impaired recognition memory in DS chimeric mice. Furthermore, we find that overexpression of OLIG2 in DS alters the expression of GABAergic neuron lineage-determining transcription factors such as DLX1 and LHX8. We further show that OLIG2 can directly bind to promoter regions of DLX1 and LHX8 to increase their expression, leading to lineage specification of interneurons. Importantly, knockdown of OLIG2 largely reverses the abnormal global gene expression profile of early stage DS neural progenitors, reduces inhibitory neuronal population in DS organoids and chimeric mouse brains, as well as improves behavioral performance of DS chimeric mice. Therefore, OLIG2 potentially is a target for developing prenatal personalized therapeutics for intellectual disability in subjects with DS