The contribution of de novo coding mutations to meningomyeloceleHa, Nisal, Tang
et alNature (2025)
Abstract: Meningomyelocele (also known as spina bifida) is considered to be a genetically complex disease resulting from a failure of the neural tube to close. Individuals with meningomyelocele display neuromotor disability and frequent hydrocephalus, requiring ventricular shunting. A few genes have been proposed to contribute to disease susceptibility, but beyond that it remains unexplained1. We postulated that de novo mutations under purifying selection contribute to the risk of developing meningomyelocele2. Here we recruited a cohort of 851 meningomyelocele trios who required shunting at birth and 732 control trios, and found that de novo likely gene disruption or damaging missense mutations occurred in approximately 22.3% of subjects, with 28% of such variants estimated to contribute to disease risk. The 187 genes with damaging de novo mutations collectively define networks including actin cytoskeleton and microtubule-based processes, Netrin-1 signalling and chromatin-modifying enzymes. Gene validation demonstrated partial or complete loss of function, impaired signalling and defective closure of the neural tube in Xenopus embryos. Our results indicate that de novo mutations make key contributions to meningomyelocele risk, and highlight critical pathways required for neural tube closure in human embryogenesis.© 2025. The Author(s), under exclusive licence to Springer Nature Limited.
Systemic Lupus Erythematosus Stimulates Chondrocyte Pyroptosis to Aggravate Arthritis via Suppression of NRF-2/KEAP-1 and NF-κB PathwayShen, Fang, Zhang
et alJ Inflamm Res (2025) 18, 4233-4250
Abstract: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by diverse clinical manifestations, including joint symptoms. Arthritis represents one of the earliest manifestations of SLE, profoundly affecting the quality of life for affected individuals, yet the underlying mechanisms of SLE-associated arthritis remain insufficiently investigated. The study aimed to investigate the impact of SLE exacerbation on arthritis using the MRL/lpr mouse model, which closely mimics human SLE manifestations.In the present study, we evaluated the impact of SLE onset on knee joint degeneration by comparing arthritic phenotype and complex molecular alterations between 6 female 14-week-old MRL/lpr mice, which manifest SLE, and MRL/MpJ mice, which remain unaffected.Our results demonstrated that MRL/lpr mice exhibited a more severe arthritic phenotype compared to MRL/MpJ mice, characterized by elevated Osteoarthritis Research Society International (OARSI) scores (P < 0.01), disrupted extracellular matrix metabolism, impaired chondrocyte proliferation and increased apoptosis. Notably, inflammatory cytokines proteins such as IL-1β and TNF-α (both P < 0.01), IL-18 and IL-6 (both P < 0.05), were significantly increased in articular cartilage of MRL/lpr mice, accompanied by increased expression of calcitonin gene-related peptide (CGRP) (P < 0.05), NETRIN-1, and NESTIN (both P < 0.01), indicating that SLE promotes inflammation response and sensory nerve ingrowth in the knee joint, contributing to the progression of arthritis. Mechanistic analysis revealed that SLE exacerbation intensified chondrocyte pyroptosis by upregulating pyroptotic-related proteins, including NLRP3, CASPASE-1, and gasdermin D (all P < 0.01), through the regulation of the nuclear factor erythroid 2-related factor (NRF-2)/KEAP-1 and nuclear factor kappa-B (NF-κB) pathway.Collectively, our findings underscore the mechanistic connection between chondrocyte pyroptosis and arthritis exacerbation in SLE, suggesting potential therapeutic targets for mitigating arthritis progression in the context of SLE.© 2025 Shen et al.
A stable NTN1 fluorescent reporter chicken reveals cell specific molecular signatures during optic fissure closureHo Ching Chan, Hardy, Requena
et alSci Rep (2025) 15 (1), 10096
Abstract: NTN1 is expressed in a wide range of developmental tissues and is essential for normal development. Here we describe the generation of a Netrin-1 reporter chicken line (NTN1-T2A-eGFP) by targeting green fluorescent protein into the NTN1 locus using CRISPR/Cas9 methodology. Our strategy gave 100% transmission of heterozygous (NTN1T2A - eGFP/+) embryos in which GFP localisation faithfully replicated endogenous NTN1 expression in the optic fissure and neural tube floorplate. Furthermore, all NTN1T2A - eGFP/+ embryos and hatched birds appeared phenotypically normal. We applied this resource to a pertinent developmental context - coloboma is a structural eye malformation characterised by failure of epithelial fusion during optic fissure closure (OFC) and NTN1 is specifically expressed in fusion pioneer cells at the edges of the optic fissure. We therefore optimised the isolation of GFP expressing cells from embryonic NTN1T2A - eGFP/+ eyes using spectral fluorescence cell-sorting and applied transcriptomic profiling of pioneer cells, which revealed multiple new OFC markers and novel pathways for developmental tissue fusion and coloboma. This work provides a novel fluorescent NTN1 chicken reporter line with broad experimental utility and is the first to directly molecularly characterise pioneer cells during OFC.© 2025. The Author(s).
Lentivirus-mediated overexpression of netrin-1/DCC co-expression promotes axonal regeneration and functional recovery in spinal cord injury via the inhibition of the NgR1-RhoA-ROCK signaling pathwayZheng, Ma, Yuan-Xia
et alTransl Neurosci (2025) 16 (1), 20250365
Abstract: Spinal cord injury (SCI) seriously affects the health of humans and quality of life, causing disabilities. Due to the ever-increasing traffic and cases of natural disasters, such as earthquakes, the incidence of SCI increases every year, thus causing a huge economic burden to society and patients. The lack of neurotrophic factors in the area affected by SCI and the presence of inhibitory factors for axonal regeneration are important reasons that make spinal cord regeneration and repair extremely difficult. Additionally, the correct projection of axons also plays an important role. As Netrin-1 is a signaling factor that guides axon growth, in this study, to determine whether Netrin-1 can promote axonal regeneration after binding to the receptor DCC following SCI, a Netrin-1/DCC co-expression recombinant lentiviral vector was constructed. This vector was used to assess the effect of Netrin-1 on the NgR1-RhoA-ROCK signaling pathway in an SCI model constructed in this study. Our results suggested that Netrin-1 exerts neuroprotective effects by inhibiting the NgR1-RhoA-ROCK signaling pathway after binding to its receptor DCC.© 2025 the author(s), published by De Gruyter.
膜杰作
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