Video Experimental Relacionado
Updated: Jun 20, 2026
05:37
Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes
Published on: April 4, 2025
El ADN G-cuadruplex unido por un ligando sintético es altamente dinámico
Prakrit V Jena1, Pravin S Shirude, Burak Okumus
1Department of Physics, Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|August 19, 2009
Resumen
Un nuevo ligando se une irreversiblemente al ADN telomérico G-cuadruplex humano, estabilizando su estructura. Esta estabilización preserva el ADN.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
- Biología Estructural Biología estructural.
Sus antecedentes:
- Los G-cuadruplexos del ADN telomérico son cruciales para la estabilidad genómica.
- Comprender las interacciones del ligando G-cuadruplex es clave para el desarrollo terapéutico.
Objetivo del estudio:
- Para investigar la interacción entre un ligando específico y el telomérico humano G-cuadruplex.
- Para caracterizar los efectos conformacionales y la dinámica de esta interacción.
Principales métodos:
- Se empleó la transferencia de energía de resonancia de fluorescencia de molécula única (smFRET).
- Se analizaron la cinética de unión y las preferencias conformacionales de un macrociclo de quinolinacarboxamida.
Principales resultados:
- El ligando exhibió una unión irreversible al telomérico G-cuadruplex.
- La unión de ligandos estabilizó selectivamente una conformación cuadruplex específica.
- El G-cuadruplex mantuvo una dinámica intrínseca de plegado/despliegue a pesar de la asociación de ligandos.
Conclusiones:
- El macrociclo de quinolinacarboxamida estabiliza el ADN telomérico G-cuadruplex.
- La estabilización ocurre sin obstaculizar la naturaleza dinámica inherente del G-cuadruplex.
- Esto ofrece una estrategia potencial para la modulación de estructuras G-cuadruplex en sistemas biológicos.
Videos de Conceptos Relacionados
00:49Ligand Binding and Linkage
Allosteric proteins have more than one ligand binding site; the binding of a ligand to any of these sites influences the binding of ligands to the other sites. When a protein is allosteric, its binding sites are called coupled or linked. In the case of enzymes, the site that binds to the substrate is known as the active site and the other site is known as the regulatory site. When a ligand binds to the regulatory site, this leads to conformational changes in the protein that can influence the...
02:13Cooperative Binding of Transcription Regulators
Transcriptional regulators bind to specific cis-regulatory sequences in the DNA to regulate gene transcription. These cis-regulatory sequences are very short, usually less than ten nucleotide pairs in length. The short length means that there is a high probability of the exact same sequence randomly occurring throughout the genome. Since regulators can also bind to groups of similar sequences, this further increases the chances of random binding. Transcriptional regulators form dimers that...
02:40Ligand Binding Sites
Proteins are dynamic macromolecules that carry out a wide variety of essential processes; however, the activities of most proteins depend on their interactions with other molecules or ions, known as ligands.
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
Protein-ligand interactions are quite specific; even though numerous potential ligands surround a cellular protein at any given time, only a particular ligand can bind to that protein. Moreover, a ligand binds only to a dedicated area on the surface of the protein, known as the...
00:43Complexometric Titration: Ligands
Different monodentate and polydentate ligands are used as complexing agents in complexometric titration reactions. The formation of complexes by mono- and bidentate ligands involves two or more intermediate steps, limiting their use as complexing agents. In comparison, polydentate ligands can form complexes with metal ions in a single-step process, facilitating sharper end points. This means polydentate ligands, such as amino carboxylic acid derivatives, are most commonly employed in...
01:03Single-Strand DNA Binding Proteins
For successful DNA replication, the unwinding of double-stranded DNA must be accompanied by stabilization and protection of the separated single strands of the DNA. This crucial task is performed by single-strand DNA-binding (SSB) proteins. They bind to the DNA in a sequence-independent manner, which means that the nitrogenous bases of the DNA need not be present in a specific order for binding of SSB proteins to it. The binding of SSB proteins straightens single-stranded DNA (ssDNA) and makes...
01:49Conserved Binding Sites
Many proteins’ biological role depends on their interactions with their ligands, small molecules that bind to specific locations on the protein known as ligand-binding sites. Ligand-binding sites are often conserved among homologous proteins as these sites are critical for protein function.
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...