Acta Biochimica et Biophysica Sinica•2024•DOI: 10.3724/abbs.2024134
SUN5, a testis-specific gene, is associated with acephalic spermatozoa syndrome (ASS). Here, we demonstrate that SUN5 is involved in mRNA export. In Sun5-knockout mice (Sun5–/–), poly(A)+ RNA accumulates in the nuclei of germ cells, leading to reduced sperm counts, decreased sperm motility and disrupted sperm head-to-tail junctions. Additionally, in the GC-2 germ cell line with RNA interference of Sun5, heterogeneous nuclear ribonucleoproteins (hnRNPs) and poly (A)+ RNA (mainly mRNA) are retained in the nucleus. Further mechanistic studies reveal that SUN5 interacts with Nxf1 (nuclear RNA export factor 1) and nucleoporin 93 (Nup93). Interference with Nup93 inhibits mRNA export. Treatment with leptomycin B to block the CRM1 pathway indicates that Sun5 regulates mRNA export through an Nxf1-dependent pathway. In Sun5–/– mice, the binding of Nxf1 and Nup93 decreases due to loss of Sun5 function, and the process of submitting Nxf1-binding mRNPs to Nup93 is inhibited, resulting in abnormal spermatogenesis. Together, these data may elucidate a novel pathway for mRNA export in male germ cells.
Acta Biochimica et Biophysica Sinica•2025•DOI: 10.3724/abbs.2025105
This review delves into the crosstalk network between oligodendrocytes and other glial cells in the context of demyelinating diseases. Oligodendrocytes, the myelin-forming cells in the central nervous system (CNS), are crucial for maintaining the function and integrity of axons and myelin sheaths. In demyelination pathologies, various factors hinder the normal differentiation of oligodendrocyte precursor cells, obstructing the myelin regeneration process, which is a primary barrier to therapeutic myelin repair. Emerging evidence highlights the critical role of glial cell interactions in CNS homeostasis and myelin regeneration, increasing interest in the treatment of demyelinating diseases. This article reviews the role of interactions between oligodendrocytes and other CNS glial cells in demyelinating and neurological diseases. Previous findings suggest that other CNS glial cells influence the survival and metabolic activity of oligodendrocytes through cell interactions, significantly affecting myelin formation and impacting demyelinating diseases characterized by myelin regeneration disorders. Targeted modulation of oligodendrocytes and their interactions with other cells at specific temporal stages may indicate a novel therapeutic direction for demyelinating diseases and offer fresh perspectives on the study of mechanisms and therapeutic approaches for related neurological conditions.
Acta Biochimica et Biophysica Sinica•2025•DOI: 10.3724/abbs.2025105
Demyelinating diseases of the central nervous system (CNS) are characterized by failed remyelination, largely due to arrested oligodendrocyte precursor cell (OPC) differentiation. This review synthesizes evidence on the crosstalk between oligodendrocytes (OLGs) and other glial cells—astrocytes, microglia, and neurons—in the context of demyelination. OLGs, the myelin-forming cells of the CNS, are essential for axonal integrity and saltatory conduction. Under pathological conditions, factors including astrocyte-derived PDGF and leukemia inhibitory factor (LIF), microglial polarization states, and neuronal activity modulate OLG survival, metabolic support, and process outgrowth. Astrocytes promote process outgrowth via basic fibroblast growth factor (bFGF) and extracellular matrix interactions, while also regulating iron metabolism and exosomal secretion from OPCs through integrin β4-mediated adhesion. Microglial heterogeneity, with M1/M2 polarization, influences neuroinflammation and remyelination outcomes. The review highlights that astrocyte activation via STAT3 signaling determines the balance between oligodendrocyte and Schwann cell remyelination. These intercellular interactions significantly impact myelin regeneration and offer potential therapeutic targets. Modulating these interactions at specific temporal stages may provide novel strategies for treating demyelinating diseases and related neurological conditions. The integration of single-cell resolution data on microglial heterogeneity and spatial-temporal dynamics is critical for developing targeted interventions.