98%
921
2 minutes
20
G-rich sequences of DNA and RNA can form G-quadruplex (G4) structures, modulating a myriad of biological processes. Thus, it is imperative to understand the structural topologies, location, and function of G4s under cell-free conditions and in the cellular milieu. In the present study, we report three small-molecule fluorescent probes based on azlactones (-) that significantly light up (∼65-135-fold) the parallel topology of the , , and mitochondrial HRCC G4 DNAs. The lead probe AZL1 exhibits a 2:1 binding stoichiometry with G4 DNA by accessing the 5' and 3'-G-quartets. It shows limited cytotoxicity and exhibits fluorescence light-up in the cytoplasm of the HeLa cells due to weak colocalization with the mitochondrial G4 DNAs along with strong colocalization with lipid droplets. These results demonstrate that azlactone-based probes are useful tools to sense G4 structures in a cell-free environment and could be further engineered for potential bioimaging and diagnostic applications.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.biochem.5c00280 | DOI Listing |
Chem Asian J
August 2025
Molecular Sensor and Supramolecular Chemistry Laboratory, Department of Chemistry, Indian Institute of Engineering Science and Technology, Shibpur, Howrah, West Bengal, 711103, India.
A turn-on fluorescent probe, TPIHB, featuring a hydrazinobenzothiazole-appended phenanthroimidazole core, was developed for dual-channel sensing of reactive oxygen species, hypochlorite, and nerve agent simulant diethyl chlorophosphate (DCP), through two distinct mechanistic pathways in biological settings and vapor-phase applications. The probe lighted up with a strong blue signal at 437 nm due to the formation of triazole TPITT through the hypochlorite-induced intramolecular oxidative cyclization. In contrast, DCP-triggered protonation of the secondary nitrogen led to the formation of ICT-enabled TPIHB-DH, resulting in a bright cyan emission at 458 nm in an aqueous THF medium.
View Article and Find Full Text PDFMikrochim Acta
August 2025
State Key Laboratory of Antiviral Drugs, Henan Joint International Research Laboratory of Environmental Pollution Control Materials, College of Chemistry and Molecular Sciences, Henan University, Kaifeng, 475004, China.
Improving the targeting of nanomedicines in cancer diagnosis and treatment can not only greatly enhance the drug efficacy, but also reduce the systemic toxicity of drugs. The design of cellulose-based nanomaterials with targeted recognition and stimulatory response to overexpressed CD44 receptor and glutathione (GSH) in the cell membrane and cytoplasm of cancer cells, respectively, can significantly improve the targeting effect and reduce the biotoxicity due to the two-site recognition effect. Herein, carboxylated nanocellulose as a carrier to covalently graft with disulfide-modified anthocyanin dye molecules (Cyss) to obtain TOCNC-Cyss, and hyaluronic acid (HA) was assembled on the surface of TOCNC-Cyss to construct cellulose-based nanocomposite TOCNC-Cyss@HA (TCH).
View Article and Find Full Text PDFBiochemistry
September 2025
Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400076, India.
G-rich sequences of DNA and RNA can form G-quadruplex (G4) structures, modulating a myriad of biological processes. Thus, it is imperative to understand the structural topologies, location, and function of G4s under cell-free conditions and in the cellular milieu. In the present study, we report three small-molecule fluorescent probes based on azlactones (-) that significantly light up (∼65-135-fold) the parallel topology of the , , and mitochondrial HRCC G4 DNAs.
View Article and Find Full Text PDFAnal Sci
August 2025
Department of Forensic Medicine, Chongqing Medical University, Chongqing, 400016, China.
MicroRNAs (miRNAs) are pivotal regulators of cellular processes, with dysregulation linked to diverse diseases, particularly cancer. Current methods, while effective, are often expensive, complex, and require sophisticated equipment. To address these limitations, we developed a label-free, one-pot miRNA detection platform integrating toehold-mediated strand displacement (TMSD) with nucleic acid sequence-based amplification (NASBA).
View Article and Find Full Text PDFDNA-based fluorescent light-up aptamers (FLAPs) are promising for bioanalytical assays because they provide a low-cost fluorescent signal readout without the need for labeling of nucleic acid signal reporters with fluorophores and/or quenchers, unlike conventional hybridization probes used for instantaneous nucleic acid detection. Instead, FLAPs non-covalently bind dye ligands , which exhibit intrinsically low fluorescence in aqueous solutions, but become highly emitting upon FLAP binding. This protocol describes an algorithm to design split light-up aptamer sensors (SLASs) utilizing DAP-10-42, the most efficient DNA FLAP reported thus far.
View Article and Find Full Text PDF