AI Networking Cookbook: Practical recipes for AI-assisted network automation and development
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The findings suggest that transient trim25 knockdown may alleviate intracellular restriction of exogenous reporter expression in PAC2 and CST cells and may provide an affordable approach for improving molecular manipulation in selected fish cell systems.
Long-term transgene silencing remains a major challenge in lentiviral gene delivery, particularly in pluripotent stem cells undergoing lineage-specific differentiation. Universal chromatin opening elements (UCOEs) have emerged as effective regulatory elements for protecting transgene expression against epigenetic silencing; however, their relatively large-size limits vector design flexibility. In the present study, we evaluated the anti-silencing activity of three next-generation UCOE constructs (1.7 kb, 1.2 kb, and a newly developed minimal 0.5 kb fragment) during long-term culture and neuronal differentiation of human induced pluripotent stem cells (iPSCs). UCOE fragments were cloned into self-inactivating lentiviral vectors and validated by restriction enzyme analysis and agarose gel electrophoresis. Lentiviral particles produced in HEK293T cells were used to transduce human iPSCs, followed by neuronal differentiation. Transgene expression was monitored for up to 60 days using fluorescence microscopy, confocal immunofluorescence, flow cytometry, and vector copy number analysis by quantitative PCR. All UCOE-containing vectors demonstrated significantly improved transgene stability compared with the UCOE-less control throughout both the undifferentiated and differentiated stages. The UCOE-containing constructs maintained substantially greater expression stability than the UCOE-less control, with the minimal 0.5 kb UCOE showing long-term performance comparable to the larger UCOE constructs. These findings demonstrate that considerable UCOE minimization can be achieved without markedly compromising anti-silencing activity, providing a potential vector-design advantage by reducing the regulatory cassette footprint and increasing available vector capacity. The compact 0.5 kb UCOE therefore represents a promising regulatory element for sustained transgene expression in stem cell engineering, disease modeling, regenerative medicine, and future gene therapy applications. However, the present study did not directly assess genomic safety, insertional effects, genotoxicity, or cellular transformation, and dedicated preclinical studies will be required to determine the long-term safety and in vivo performance of this compact UCOE configuration.
Unique To progress transfection productivity in Trypanosomacruzi, we created a modern electroporation protocol and expression vectors which utilize luciferase and green and ruddy fluorescent proteins as columnist qualities. In transients transfections, the electroporation conditions reported here brought about in luciferase expression 100 times higher than the levels gotten with already described protocols. To confirm whether groupings containing different trans-splicing signals impact columnist gene expression, we compared DNA parts corresponding to 5¢ untranslated furthermore intergenic (5¢ UTR furthermore Ig) regions from GAPDH, TcP2b, a-and b-tubulin and amastin qualities. Vectors containing groupings derived from the primary four qualities displayed comparative efficiencies and brought about in luciferase expression in transiently transfected epimastigotes that was up to 10 timeshigher than that for a control vector. In differentiate, the amastin 5¢ UTR also Ig come about in lower levels of columnist gene expressionWe too developed a vector containing an expression cassette planned to be focused on to the tubulin locus of the parasite[1].
Stable expression of regulatory non‐coding RNAs enables targeted cell engineering in Chinese hamster ovary (CHO) cells but commonly relies on random integration, resulting in variable expression. Here, we establish a transposase‐mediated platform for stable microRNA (miRNA) expression in CHO cells and demonstrate the first application of a DNA transposon system for long‐term miRNA genome integration. Using miR‐3096b‐5p, we compared piggyBac‐mediated integration with conventional random integration in antibody‐producing CHO cells. Transposase‐mediated integration enabled rapid generation of stable cell pools with higher fractions of GFP‐expressing cells. Both integration strategies supported comparable growth, viability, and antibody production in batch cultures, indicating that transposase‐mediated miRNA integration does not compromise bioprocess performance. At the molecular level, transposase‐mediated integration resulted in significantly higher transgene copy numbers and markedly increased miRNA expression, translating into stronger and more consistent regulation of the target genes Fuk and Gmds. By combining high integration efficiency and expression stability with the regulatory potential of miRNAs, this approach expands the applicability of transposase systems beyond protein‐coding transgenes and provides a robust platform for precise and durable post‐transcriptional gene regulation in CHO cell engineering.
Cas9 ablation enabled restoration of CUL4B expression and function following introduction of a CUL4B expression plasmid, providing proof of concept for a broadly applicable approach to studying protein function through rescue experiments.
The knockout and re-expression platform provides a useful gene editing tool for primary T cells in fundamental research and immunotherapy development and can be used to generate gene-edited primary T cells for in vivo studies, such as the quantification of anti-tumor responses.
Cellular senescence is associated with profound alterations in cellular physiology, including reduced membrane fluidity, impaired endosomal trafficking, diminished endocytic capacity, and increased extracellular RNase activity, all of which hinder efficient mRNA delivery. These barriers have limited the application of RNA-based approaches in senescent cells, particularly for delivering large therapeutic transcripts. This protocol describes an optimized reverse-transfection method for the efficient delivery of modified messenger RNA (mRNA) into senescent human fibroblasts. Although human telomerase reverse transcriptase (hTERT) mRNA was used as the model transcript, the workflow is broadly applicable to other mRNAs. In contrast to conventional transfection methods, in which RNA-lipid complexes are added to the culture medium after cell attachment, reverse transfection deposits the complexes onto the culture surface before cell seeding, enabling direct interaction between attaching cells and transfection complexes. To maximize transfection efficiency, the protocol incorporates nucleoside-modified mRNA containing pseudouridine and 5-methylcytidine, extended poly(A) tails, optimized complex-formation timing, RNase inhibition, transient elevation of endosomal pH with chloroquine, increased cell-seeding density, and extended incubation periods. Using this approach, transfection efficiencies of approximately 50%-80% were achieved in senescent fibroblasts following delivery of a 5 kb hTERT mRNA transcript. Peak telomerase activity was detected 24-48 h after transfection. A single transfection cycle produced measurable telomere elongation, whereas three sequential transfections resulted in substantial but finite telomere extension. Partial reversal of senescence-associated phenotypes was detectable within 72-96 h, including reduced senescence-associated β-galactosidase activity, decreased p16 and p21 expression, restoration of cell morphology, and extension of replicative lifespan. The delivered hTERT mRNA was degraded within 72-96 h, and immortalization was not observed. This protocol provides a practical approach for transient mRNA delivery into senescent cells and may be adaptable to a wide range of cell types and species.
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