Single cell sequencing data of islets from WT and Npc1KO mice
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ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE237585 | GEO | 2024/03/27
REPOSITORIES: GEO
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Project description:Cholesterol and phosphoinositides (PI) are two critically important lipids that are found in cellular membranes and dysregulated in many disorders. Therefore, uncovering molecular pathways connecting these essential lipids may offer new therapeutic insights. We report that loss of function of lysosomal Niemann-Pick Type C1 (NPC1) cholesterol transporter, which leads to neurodegenerative NPC disease, initiates a signaling cascade that alters the cholesterol/phosphatidylinositol 4-phosphate (PtdIns4P) countertransport cycle between Golgi-endoplasmic reticulum (ER), as well as lysosome-ER membrane contact sites (MCS). Central to these disruptions is increased recruitment of phosphatidylinositol 4-kinases-PI4KIIα and PI4KIIIβ-which boosts PtdIns4P metabolism at Golgi and lysosomal membranes. Aberrantly increased PtdIns4P levels elevate constitutive anterograde secretion from the Golgi complex, and mTORC1 recruitment to lysosomes. NPC1 disease mutations phenocopy the transporter loss of function and can be rescued by inhibition or knockdown of either key phosphoinositide enzymes or their recruiting partners. In summary, we show that the lysosomal NPC1 cholesterol transporter tunes the molecular content of Golgi and lysosome MCS to regulate intracellular trafficking and growth signaling in health and disease.
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Project description:Cholesterol is required for oligodendrocyte maturation and CNS myelination. Here, we demonstrate an essential role for the intracellular cholesterol transporter NPC1 in these processes. NPC1 functions in late endosomes and lysosomes to efflux unesterified cholesterol, and its deficiency causes Niemann-Pick disease Type C, an autosomal recessive lysosomal disorder characterized by progressive neurodegeneration and early death. To identify cell types and pathways affected early in pathogenesis, we performed single nuclear RNA-seq on the forebrain of Npc1-/- mice at P16. This analysis uncovered striking transcriptional changes in the oligodendrocyte lineage during the period of developmental myelination, accompanied by diminished maturation of myelinating oligodendrocytes. Unexpectedly, we identified a significant upregulation of genes associated with neurogenesis and synapse formation in Npc1-/- oligodendrocyte lineage cells, reflecting diminished gene silencing by H3K27me3 and H3K9me3.
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Project description:Cholesterol is required for oligodendrocyte maturation and CNS myelination. Here, we demonstrate an essential role for the intracellular cholesterol transporter NPC1 in these processes. NPC1 functions in late endosomes and lysosomes to efflux unesterified cholesterol, and its deficiency causes Niemann-Pick disease Type C, an autosomal recessive lysosomal disorder characterized by progressive neurodegeneration and early death. To identify cell types and pathways affected early in pathogenesis, we performed single nuclear RNA-seq on the forebrain of Npc1-/- mice at P16. This analysis uncovered striking transcriptional changes in the oligodendrocyte lineage during the period of developmental myelination, accompanied by diminished maturation of myelinating oligodendrocytes. Unexpectedly, we identified a significant upregulation of genes associated with neurogenesis and synapse formation in Npc1-/- oligodendrocyte lineage cells, reflecting diminished gene silencing by H3K27me3 and H3K9me3. Npc1-/- oligodendrocyte progenitor cells reproduced impaired maturation in vitro and this phenotype was rescued by treatment with GSK-J4, a small molecule inhibitor of H3K27 demethylases. This study sought to determine the genes being directly impacted by the epigenetic dysfunction at H3K27.
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Project description:Cholesterol is required for oligodendrocyte maturation and CNS myelination. Here, we demonstrate an essential role for the intracellular cholesterol transporter NPC1 in these processes. NPC1 functions in late endosomes and lysosomes to efflux unesterified cholesterol, and its deficiency causes Niemann-Pick disease Type C, an autosomal recessive lysosomal disorder characterized by progressive neurodegeneration and early death. To identify cell types and pathways affected early in pathogenesis, we performed single nuclear RNA-seq on the forebrain of Npc1-/- mice at P16. This analysis uncovered striking transcriptional changes in the oligodendrocyte lineage during the period of developmental myelination, accompanied by diminished maturation of myelinating oligodendrocytes. Unexpectedly, we identified a significant upregulation of genes associated with neurogenesis and synapse formation in Npc1-/- oligodendrocyte lineage cells, reflecting diminished gene silencing by H3K27me3 and H3K9me3. Npc1-/- oligodendrocyte progenitor cells reproduced impaired maturation in vitro and this phenotype was rescued by treatment with GSK-J4, a small molecule inhibitor of H3K27 demethylases. This study sought to determine the genes being directly impacted by the epigenetic dysfunction at H3K27.
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