Video Experimental Relacionado
Updated: Jul 6, 2026
10:59
Atomic Force Microscopy Investigations of DNA Lesion Recognition in Nucleotide Excision Repair
Published on: May 24, 2017
Alteración conformacional específica del sitio del complejo Oct-1 POU dominio-ADN como base para el reconocimiento
Cell
|December 2, 1994
Resumen
El elemento regulador que flanquea el dominio POU dicta la interacción Vmw65 (VP16) al inducir una conformación específica ligada al ADN. Las mutaciones revelan que este cambio conformacional es crucial para el reconocimiento de Vmw65, no solo para la unión POU.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Interacciones entre proteínas y ADN.
- El Reglamento de transcripción.
Sus antecedentes:
- El dominio POU es un motivo de unión al ADN crucial para la regulación de la transcripción.
- Vmw65 (VP16) es un transactivador viral que interactúa con las proteínas del dominio POU.
- Los elementos reguladores que flanquean los sitios de unión al ADN pueden influir en la formación y función del complejo proteína-ADN.
Objetivo del estudio:
- Investigar el papel de un elemento de acción cis que flanquea el sitio octámero en la formación del complejo de dominio POU-ADN y la interacción Vmw65 (VP16).
- Determinar si este elemento flanqueante induce cambios conformacionales en el dominio POU tras la unión al ADN.
- Para aclarar la base estructural de la selectividad Vmw65 (VP16) en el reconocimiento de dominio POU.
Principales métodos:
- Mutagénesis dirigida al sitio del elemento regulador de acción cis y el homeodominio del dominio POU.
- Análisis del dominio POU que se une a los motivos del ADN.
- Evaluación de la interacción de Vmw65 (VP16) con los complejos POU-DNA modificados.
Principales resultados:
- El elemento de acción cis flanqueante, aunque no es esencial para la unión de POU, induce una alteración conformacional en el complejo dominio-ADN POU.
- Una sola sustitución en el elemento de flanqueo distorsiona el complejo POU, impidiendo la interacción Vmw65 (VP16) sin afectar la unión POU.
- La sustitución de un residuo de homeodominio involucrado en la región de contacto GARAT altera los patrones de unión al ADN y reduce el reconocimiento de Vmw65 (VP16).
Conclusiones:
- Vmw65 (VP16) reconoce una conformación específica del dominio POU que es inducida por la presencia de la región GARAT flanqueante.
- El elemento regulador flanqueante juega un papel crítico en la modulación de la función del dominio POU y la transactivación Vmw65 (VP16).
- La plasticidad estructural del dominio POU es clave para las interacciones selectivas proteína-proteína en la regulación transcripcional.
Videos de Conceptos Relacionados
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...
02:02DNA Topoisomerases
Topoisomerases are enzymes that relax overwound DNA molecules during various cell processes, including DNA replication and transcription. These enzymes regulate positive and negative DNA supercoiling without changing the nucleotide sequence. DNA overwinding in a clockwise direction results in positively supercoiled DNA, whereas underwinding in a counterclockwise direction produces negatively supercoiled DNA.
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
Types and Mechanism of action
Topoisomerases are divided into two main types. Type I...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
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...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...