Experimental cell research最新文献

Osteoblasts, specialized bone-forming cells, differentiate from mesenchymal stem cells (MSCs). In recent years, stem cell-derived osteoblasts have emerged as potential choices for the treatment of bone-related disorders. A complex network of regulatory elements, including signaling pathways, transcription factors, and non-coding RNAs (ncRNAs), orchestrates MSCs differentiation. Among the key regulators of osteoblast differentiation is Runt-related transcription factor 2 (Runx2), a master transcription factor essential for osteogenic commitment. Elucidating the molecular mechanisms that regulate Runx2 expression and function is critical for the treatment of osteoblast-related disease. Runx2 is regulated through signaling pathways and a complex, post-transcriptional competing endogenous RNA (ceRNA) network. In this network, circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs) sequester microRNAs (miRNAs), thereby fine-tuning Runx2 expression. Signaling pathways can also indirectly regulate Runx2 by inducing the expression of osteo-regulatory miRNAs. This review highlights the regulatory role of Runx2 during osteoblastic differentiation. It also explores how signaling pathways, lncRNAs, circRNAs, and other factors interact with Runx2-regulatory miRNAs involved in this process.

Efficient regeneration of plants from single cells is a critical yet challenging step for applying modern biotechnologies to sugarcane (Saccharum spp.), a vital sugar and bioenergy crop. The main obstacles include low embryogenic competence and recalcitrant differentiation. Here, we established a standardized, high-efficiency single-cell regeneration system for the model cultivar ROC22 by systematically optimizing key hormonal and physiological parameters. Embryogenic callus, induced from young leaf sheaths, was used to establish suspension cultures. A homogeneous population of single cells with 58% viability was isolated via 200-mesh sieve filtration. Dynamic growth analysis identified 2.0 mg·L^-1 2,4-dichlorophenoxyacetic acid (2,4-D) as optimal for proliferation, yielding a peak density of 2.4 × 10⁵ cells/mL. The differentiation of compact callus was maximized on medium containing 2.0 mg·L^-1 6-benzylaminopurine (6-BA) and 0.5 mg·L^-1 kinetin (KT), resulting in minimal browning (17.8%) and large callus clusters (1.52 cm in diameter). Ultimately, a high green plantlet regeneration efficiency of 81.1% was achieved on a regeneration medium with half-strength MS macronutrients, 3 mg·L^-1 naphthaleneacetic acid (NAA), and 0.5 mg·L^-1 6-BA. This reproducible and efficient system provides a robust platform for genetic transformation and single-cell-based studies in sugarcane.

Nuclear factor erythroid 2-related factor 2 (Nrf2) is a basic leucine zipper transcription factor best regulating cellular defense mechanisms. However, its role in human adipocyte differentiation remains poorly understood. Here, we investigated the contribution of Nrf2 to adipocyte differentiation using an in vivo teratoma model, a straightforward assay for evaluating the differentiation potential of human embryonic stem cells (hESCs). We found that enhanced Nrf2 signaling, induced by KEAP1 gene deletion in hESCs, increased both the size and area of adipocytes within teratomas. Quantitative transcriptomic analysis of teratomas (TeratoScore) and the Ingenuity Pathway Analysis indicated activation of an adipogenesis-related signaling network, as evidenced by increased expression of FABP4, PPARG, ADIPOQ, and CEBPA in KEAP1-knockout teratomas. Stepwise in vitro differentiation of hESCs into adipocytes further supported a pro-adipogenic role for Nrf2, as shown by increased lipid-droplet accumulation. Notably, we identified PAX3 as a transcriptional target associated with Nrf2 activation, suggesting a potential link between Nrf2 signaling and adipogenic regulation. Together, these findings reveal a previously underappreciated role for Nrf2 in human adipogenesis.

Diabetes-induced hyperglycemia promotes retinal capillary endothelial cell dysfunction, contributing to diabetic retinopathy. In this study, we reveal that high glucose (HG) drives ferroptosis and inflammation through lactate-mediated GPX4 lactylation. HG conditions enhance glycolysis and lactate production, leading to increased lactylation of GPX4, a process mediated by the acetyltransferases KAT5 and KAT8. GPX4 lactylation reduces its antioxidant function, promoting lipid peroxidation, ferroptosis, and inflammation. Specifically, HG exposure significantly increases malondialdehyde (MDA) levels, decreases GSH levels, and elevates lipid ROS, while simultaneously inducing pro-inflammatory cytokine expression (IL6, TNF, and IL1B). Inhibition of KAT5 and KAT8 markedly reduces GPX4 lactylation, restores redox balance, suppresses ferroptosis, and mitigates inflammation. Collectively, our findings identify KAT5- and KAT8-mediated GPX4 lactylation as a key mechanism underlying HG-induced ferroptosis and inflammation in diabetic retinopathy, highlighting its potential as a promising therapeutic target.

The development of a well-organised genome represents a hallmark in the evolution of species. In mammals, the nucleus of each cell is characterised by the presence of different compartments, among others nuclear speckles, membrane-less organelles that are self-shaped by liquid droplet-like phase separation. Functioning in the organisation of the transcription and splicing machinery, nuclear speckles are highly dynamic, moving and rearranging within the nucleus according to the needs of the cell. In line with a role of actin dynamics in speckle function, we could previously demonstrate that the actin-binding protein Simiate is not only enriched in nuclear speckles, but also able to associate with nuclear isoforms of the Focal Adhesion Kinase FAK1. Furthermore, nuclear speckles have recently been suggested to consist of specific sub-domains involved in the spatial organisation of chromatin handling and mRNA processing. In this study, we therefore examined the sub-speckular organisation of FAK1 and Simiate in mouse brain slices using three-dimensional reconstructions and stimulated emission depletion (STED) microscopy. While FAK1 is predominantly localised in peripheral areas, Simiate is highly enriched in the core domain. Aside, Simiate is also seen in the surrounding shell, and minor amounts of FAK1 are detected in the core domain. As the number of speckles increases, FAK1 is found to diminish from the core domain, whereas peripheral numbers remain constant. Both proteins, Simiate and FAK1, are organised in spherical clusters, which may occasionally colocalise in peripheral as well as core domains. Although our data obtained from mouse brain slices are merely descriptive, they may suggest for dynamic rearrangement of FAK1.

Background: Aortic dissection (AD) is a life-threatening vascular disease whose pathogenesis involves dysfunction of vascular smooth muscle cells (VSMCs) and cell death. This study aimed to investigate the role of the MT1E/LncRNA NEAT1/SLC39A14 axis in AD and its molecular mechanism in regulating ferroptosis.

Methods: The correlation between ferroptosis and AD was evaluated using single-sample gene set enrichment analysis (ssGSEA). Weighted gene co-expression network analysis (WGCNA) based on the GSE153434 dataset was performed to identify key modules. Differentially expressed genes were screened through GO, KEGG enrichment analyses, and protein-protein interaction (PPI) network analysis. The functions and interactions of MT1E, LncRNA NEAT1, and SLC39A14 were validated using RT-PCR, Western Blot, immunohistochemistry, Co-IP assay, RIP assay, and luciferase reporter assays. A mouse model was constructed to evaluate the role of MT1E in AD pathological injury and ferroptosis.

Results: AD was significantly associated with ferroptosis. WGCNA identified a blue module highly correlated with ferroptosis, and 236 differentially expressed genes were screened. MT1E, LncRNA NEAT1, and SLC39A14 were significantly upregulated in aortic tissues of AD patients. Knockdown of MT1E inhibited AngII-induced VSMC proliferation, migration, and ferroptosis, and restored the expression of VSMC phenotypic transformation markers. MT1E activates NEAT1 expression by forming a complex with YBX1, while MT1E activates NEAT1 through zinc ion release-mediated regulation of SFPQ and NONO. Besides, luciferase reporter assays demonstrated the direct binding of LncRNA NEAT1 to SLC39A14. Overexpression of LncRNA NEAT1 reversed the inhibitory effects of MT1E knockdown on VSMC proliferation, migration, and ferroptosis. Overexpression of SLC39A14 counteracted the effects of MT1E or LncRNA NEAT1 knockdown on VSMCs. Mouse model experiments validated the critical role of MT1E in AD pathological injury and ferroptosis.

Conclusion: This study reveals that MT1E plays a pivotal role in AD by targeting LncRNA NEAT1 to regulate SLC39A14-mediated ferroptosis. These findings provide novel insights into the molecular mechanisms of AD and offer potential therapeutic targets for related diseases.