Video Experimental Relacionado

Updated: Jun 20, 2026

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes

Single-Molecule Fluorescence Visualization of DNA Polymerase Dynamics at G-Quadruplexes

Published on: April 4, 2025

Una secuencia rica en G dentro del promotor del oncogén c-kit forma un G-cuadruplex paralelo que tiene dinámicas

Shang-Te Danny Hsu¹, Peter Varnai, Anthony Bugaut

¹University Chemical Laboratory, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, United Kingdom.

Journal of the American Chemical Society

|August 27, 2009

Resumen

Las secuencias de ADN ricas en guanina forman estructuras G-cuadruplex en los promotores de genes. Este estudio revela que el c-kit2 G-quadruplex existe como un conjunto dinámico de estructuras similares, crucial para la comprensión de la regulación oncogénica.

Área de la Ciencia:

Biología Molecular Biología Molecular
Biología Estructural Biología estructural.
La bioquímica es la bioquímica.

Sus antecedentes:

Las secuencias de ADN ricas en guanina forman estructuras G-cuadruplexas.
Estas estructuras se encuentran en regiones promotoras de genes, especialmente proto-oncogenes.
El plegado G-cuadruplex es dependiente de la condición y estructuralmente polimórfico.

Objetivo del estudio:

Para investigar la estructura y la dinámica del motivo c-kit2 G-cuadruplex.
Para comprender el comportamiento estructural de un G-cuadruplex en el promotor de oncogenes c-kit.
Para identificar distintos estados estructurales y sus dinámicas de interconversión.

Principales métodos:

Espectroscopia de resonancia magnética nuclear (RMN) en estado de solución.
Experimentos de intercambio de hidrógeno y deuterio por espectroscopia de RMN.
Análisis estructural de la formación de G-cuadruplex en presencia de iones de potasio.

Principales resultados:

El motivo c-kit2 forma una estructura G-cuadruplex de tipo hélice de cadena paralela.
Un conjunto de conformaciones similares existe en solución.
Se identificaron al menos dos subestados dinámicamente distintos, que se interconectan lentamente en la escala de tiempo de la RMN.

Conclusiones:

El c-kit2 G-cuadruplex exhibe un polimorfismo estructural dinámico.
Comprender estas dinámicas es clave para su función en la regulación génica.
La espectroscopia de RMN es efectiva para caracterizar estructuras y dinámicas complejas de G-cuadruplex.

Más Videos Relacionados

Analysis of the c-KIT Ligand Promoter Using Chromatin Immunoprecipitation

Analysis of the c-KIT Ligand Promoter Using Chromatin Immunoprecipitation

Published on: June 27, 2017

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines

In Vitro Chemical Mapping of G-Quadruplex DNA Structures by Bis-3-Chloropiperidines

Published on: May 12, 2023

Videos de Conceptos Relacionados

Activation and Inactivation of G Proteins

Activation and Inactivation of G Proteins

Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high affinity and are together...

The Eukaryotic Promoter Region

The Eukaryotic Promoter Region

The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...

Small GTPases - Ras and Rho

Small GTPases - Ras and Rho

Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:

The Ras Gene

The Ras Gene

The Ras-gene-encoded proteins are regulators of signaling pathways controlling cell proliferation, differentiation, or cell survival. The Ras-gene family in humans constitutes three primary members—the HRas, NRas, and KRas. These genes code for four functionally distinct yet closely related proteins—the HRas, NRas, KRas4A, and KRas4B. The involvement of mutant Ras genes in human cancer was first discovered in 1982 and is among the most common causes of human tumorigenesis.
Ras is a superfamily...

Cooperative Binding of Transcription Regulators

Cooperative 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...

Inhibition of Cdk Activity

Inhibition of Cdk Activity

The orderly progression of the cell cycle depends on the activation of Cdk protein by binding to its cyclin partner. However, the cell cycle must be restricted when undergoing abnormal changes. Most cancers correlate to the deregulated cell cycle, and since Cdks are a central component of the cell cycle, Cdk inhibitors are extensively studied to develop anticancer agents. For instance, cyclin D associates with several Cdks, such as Cdk 4/6, to form an active complex. The cyclin D-Cdk4/6 complex...