Project description:Nucleoporins (Nups) are involved in neural development, and alterations in Nup genes are linked to human neurological diseases. However, physiological functions of specific Nups and the underlying mechanisms involved in these processes remain elusive. Here, we show that tissue-specific depletion of the nucleoporin Seh1 causes dramatic myelination defects in the CNS. Although proliferation is not altered in Seh1-deficient oligodendrocyte progenitor cells (OPCs), they fail to differentiate into mature oligodendrocytes, which impairs myelin production and remyelination after demyelinating injury. Genome-wide analyses show that Seh1 regulates a core myelinogenic regulatory network and establishes an accessible chromatin landscape. Mechanistically, Seh1 regulates OPCs differentiation by assembling Olig2 and Brd7 into a transcription complex at nuclear periphery. Together, our results reveal that Seh1 is required for oligodendrocyte differentiation and myelination by promoting assembly of an Olig2-dependent transcription complex and define a nucleoporin as a key player in the CNS.
Project description:Nuclear pore complex components (Nups) are involved in neural development and alterations in Nup genes are linked to human neurological diseases. However, the physiological functions of specific Nups and the underlying mechanisms involved in these processes remain elusive. Here we show that tissue-specific depletion of nucleoporin Seh1 causes dramatic myelination defects in the Central Nervous System (CNS). Seh1-deficient Oligodendrocyte Progenitor Cells (OPCs) proliferate properly, but fail to differentiate into mature oligodendrocytes, which impairs myelin production and remyelination after demyelinating injury. Genome-wide analyses show that Seh1 regulates a core myelinogenic regulatory network and depletion of Seh1 alters open chromatin configurations at its target genes. Mechanistically, Seh1 regulates OPCs differentiation by assembling Olig2 and Brd7 into a transcription complex at nuclear pores. Together, our results reveal that Seh1 is required for oligodendrocyte differentiation and myelination by promoting assembly of an Olig2-dependent transcription complex and expose nucleoporins as key players in the CNS.
Project description:Nuclear pore complex components (Nups) are involved in neural development and alterations in Nup genes are linked to human neurological diseases. However, the physiological functions of specific Nups and the underlying mechanisms involved in these processes remain elusive. Here we show that tissue-specific depletion of nucleoporin Seh1 causes dramatic myelination defects in the Central Nervous System (CNS). Seh1-deficient Oligodendrocyte Progenitor Cells (OPCs) proliferate properly, but fail to differentiate into mature oligodendrocytes, which impairs myelin production and remyelination after demyelinating injury. Genome-wide analyses show that Seh1 regulates a core myelinogenic regulatory network and depletion of Seh1 alters open chromatin configurations at its target genes. Mechanistically, Seh1 regulates OPCs differentiation by assembling Olig2 and Brd7 into a transcription complex at nuclear pores. Together, our results reveal that Seh1 is required for oligodendrocyte differentiation and myelination by promoting assembly of an Olig2-dependent transcription complex and expose nucleoporins as key players in the CNS.
Project description:Nuclear pore complex components (Nups) are involved in neural development and alterations in Nup genes are linked to human neurological diseases. However, the physiological functions of specific Nups and the underlying mechanisms involved in these processes remain elusive. Here we show that tissue-specific depletion of nucleoporin Seh1 causes dramatic myelination defects in the Central Nervous System (CNS). Seh1-deficient Oligodendrocyte Progenitor Cells (OPCs) proliferate properly, but fail to differentiate into mature oligodendrocytes, which impairs myelin production and remyelination after demyelinating injury. Genome-wide analyses show that Seh1 regulates a core myelinogenic regulatory network and depletion of Seh1 alters open chromatin configurations at its target genes. Mechanistically, Seh1 regulates OPCs differentiation by assembling Olig2 and Brd7 into a transcription complex at nuclear pores. Together, our results reveal that Seh1 is required for oligodendrocyte differentiation and myelination by promoting assembly of an Olig2-dependent transcription complex and expose nucleoporins as key players in the CNS.
Project description:Cell membrane thyroid hormone (TH) transport can be facilitated by the monocarboxylate transporter 8 (MCT8), encoded by the solute carrier family 16 member 2 (SLC16A2) gene. Human mutations of the gene, SLC16A2, result in the X-linked-inherited psychomotor retardation and hypomyelination disorder, Allan-Herndon-Dudley syndrome (AHDS). We posited that abrogating MCT8-dependent TH transport limits oligodendrogenesis and myelination. We show that human oligodendrocytes (OL), derived from the NKX2.1-GFP human embryonic stem cell (hESC) reporter line, express MCT8. Moreover, treatment of these cultures with DITPA (an MCT8-independent TH analog), up-regulates OL differentiation transcription factors and myelin gene expression. DITPA promotes hESC-derived OL myelination of retinal ganglion axons in co-culture. Pharmacological and genetic blockade of MCT8 induces significant OL apoptosis, impairing myelination. DITPA treatment limits OL apoptosis mediated by SLC16A2 down-regulation primarily signaling through AKT phosphorylation, driving myelination. Our results highlight the potential role of MCT8 in TH transport for human OL development and may implicate DITPA as a promising treatment for developmentally-regulated myelination in AHDS.
