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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. • Nucleoporin Seh1 is required for OPC differentiation • Seh1 is essential for CNS myelination and remyelination • Seh1 forms a complex with Olig2 at nuclear periphery • Seh1 recruits Olig2 and Brd7 to promote oligodendrocyte development Liu et al. demonstrate that the nucleoporin Seh1 functions in oligodendrocyte differentiation, myelination, and post-injury remyelination by assembling a Seh1/Olig2/Brd7 transcription complex at nuclear periphery. [ABSTRACT FROM AUTHOR]

Summary Astrocyte dysfunction and inflammation are associated with the pathogenesis of major depressive disorder (MDD). However, the mechanisms underlying these effects remain largely unknown. Here, we found that multiple endocrine neoplasia type 1 (Men1 ; protein: menin) expression is attenuated in the brain of mice exposed to CUMS (chronic unpredictable mild stress) or lipopolysaccharide. Astrocyte-specific reduction of Men1 (GcKO) led to depressive-like behaviors in mice. We observed enhanced NF-κB activation and IL-1β production with menin deficiency in astrocytes, where depressive-like behaviors in GcKO mice were restored by NF-κB inhibitor or IL-1β receptor antagonist. Importantly, we identified a SNP, rs375804228, in human MEN1 , where G503D substitution is associated with a higher risk of MDD onset. G503D substitution abolished menin-p65 interactions, thereby enhancing NF-κB activation and IL-1β production. Our results reveal a distinct astroglial role for menin in regulating neuroinflammation in depression, indicating that menin may be an attractive therapeutic target in MDD. Highlights • Astroglia menin deficiency leads to depressive-like behaviors in mice • Menin reduction in astrocytes promotes IL-1β generation through NF-κB activation • NF-κB and IL-1β inhibitors attenuate the depressive-like phenotypes • A MEN1 SNP associated with MDD risk leads to aberrant NF-κB activation Mechanisms underlying astrocyte-mediated neuroinflammation in depression remain unclear. Menin regulates NF-κB activity in astrocytes to promote neuroinflammation. Clinically, a MEN1 SNP is associated with the onset of depression. This study reveals a distinct role for menin in neuroinflammation and depression. [ABSTRACT FROM AUTHOR]

The pathology of Alzheimer's disease (AD) is featured with extracellular amyloid-β (Aβ) plaques, whose impact on the mechanical properties of the surrounding brain tissues is unclear. Microglia sense and integrate biochemical cues of the microenvironment. However, whether the microglial mechanosensing pathways influence AD pathogenesis is unknown. Here, we surveyed the elevated stiffness of Aβ-plaque-associated tissues and observed the selective upregulation of the mechanosensitive ion channel Piezo1 in Aβ-plaque-associated microglia. Piezo1 sensed the stiffness stimuli of Aβ fibrils and subsequently induced Ca 2+ influx for microglial clustering, phagocytosis, and compacting of Aβ plaques. Microglia lacking Piezo1 led to the exacerbation of Aβ pathology and cognitive decline, whereas pharmacological activation of microglial Piezo1 ameliorated brain Aβ burden and cognitive impairment in 5 × FAD mice. Together, our results reveal that Piezo1, a mechanosensor of Aβ fibril stiffness in microglia, represents a potential therapeutic target for AD., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)