[Synthesis of a Bisbenzoxazole Analogue of Hoechst 33258 as a Potential GC-Selective DNA Ligand].

Using a computer modeling approach, we proposed a structure for a potential GC-specific DNA ligand, which could form a complex with DNA in the minor groove similar to that formed by Hoechst 33258 at DNA AT-enriched sites. According to this model, , a bisbenzoxazole ligand, was synthesized. The results of spectrophotometric methods supported the complex formation of the compound under study with DNA differing in the nucleotide composition.

Dissecting the Kaiso binding profile in clear renal cancer cells.

Background: There has been a notable increase in interest in the transcriptional regulator Kaiso, which has been linked to the regulation of clonal hematopoiesis, myelodysplastic syndrome, and tumorigenesis. Nevertheless, there are no consistent data on the binding sites of Kaiso in vivo in the genome. Previous ChIP-seq analyses for Kaiso contradicted the accumulated data of Kaiso binding sites obtained in vitro.

Distinctive aspects of ligand binding to G4 DNA structure flanked by the double helix.

Except for telomeres, G4 DNA structures in the human genome can be formed only within the context of double-stranded DNA. DNA duplexes flanking the G4 structure may potentially affect the G4 architecture and the binding of G4-specific ligands. Here, we examine the interaction of TMPyP4, NMM, and PDS ligands with three structures formed by the same DNA fragment containing the (GGGT) sequence: the G4 in duplex (dsG4), G4 in single-stranded DNA (ssG4) and perfect duplex DNA (ds).

Enhancement of intrinsic guanine fluorescence by protonation in DNA of various structures.

Understanding the diversity of DNA structure and functions in biology requires tools to study this biomolecule selectively and thoroughly. Fluorescence methods are powerful technique for non-invasive research. Due to the low quantum yield, the intrinsic fluorescence of nucleotides has not been considered for use in the detection and differentiation of nucleic acid bases.

Quenching of G4-DNA intrinsic fluorescence by ligands.

G-quadruplex (G4) structures formed by the guanine-rich DNA regions exhibit several distinctive optical properties, including UV absorption and circular dichroism spectra. Some G4 DNA possess intrinsic UV fluorescence whose origin is not completely clear to date. In this work, we study the effect of TMPyP4 and Methylene Blue on the intrinsic fluorescence of the dimeric G4 DNA structure formed by two d(GT) sequences.