Video Experimental Relacionado
Updated: May 5, 2026

10:40
Assembly of Nucleosomal Arrays from Recombinant Core Histones and Nucleosome Positioning DNA
Published on: September 11, 2013
22.1K
La proteína H-NS asociada a la cromatina interactúa con el ADN curvo para influir en la topología del ADN y la
T A Owen-Hughes1, G D Pavitt, D S Santos
1Imperial Cancer Research Fund, University of Oxford, John Radcliffe Hospital, England.
Cell
|October 16, 1992
Resumen
La proteína bacteriana H-NS se une al ADN curvo, regulando la expresión génica. Esta interacción es crucial para la osmorregulación del promotor proU e influye en la topología del ADN.
Área de la Ciencia:
- La genética bacteriana es genética bacteriana.
- Biología molecular La biología molecular.
- La estructura de la cromatina en su estructura.
Sus antecedentes:
- Las proteínas asociadas a nucleóides (NAP) como el H-NS son abundantes en las bacterias.
- El H-NS juega un papel en la compactación del ADN y regula varios procesos celulares.
- El promotor proU está regulado osmóticamente, un factor clave en la adaptación bacteriana.
Objetivo del estudio:
- Para dilucidar el mecanismo de acción de H-NS en el promotor proU regulado osmóticamente.
- Para investigar el papel de la curvatura del ADN en la regulación génica mediada por H-NS.
- Para entender cómo H-NS influye en la topología del ADN in vivo.
Principales métodos:
- Estudiando la interacción de H-NS con elementos de ADN curvo in vitro.
- Utilizando genes reporteros luxAB y lacZ para evaluar los patrones de transcripción.
- Analizando el efecto de H-NS en el número de enlace del plásmido in vivo.
Principales resultados:
- La interacción de H-NS con un elemento de ADN curvo aguas abajo es esencial para la regulación del promotor proU.
- Las secuencias de ADN curvas heterólogas pueden reemplazar funcionalmente la curva proU.
- H-NS se une preferentemente a las secuencias de ADN curvas in vitro.
- Las interacciones H-NS-ADN in vivo afectan el número de enlace del plásmido, lo que indica un papel en el control de la topología del ADN.
Conclusiones:
- La curvatura del ADN es un determinante crítico para la unión y función de H-NS.
- Los cambios mediados por H-NS en la topología del ADN están involucrados en la osmorregulación del promotor proU.
- Este estudio proporciona información sobre los mecanismos moleculares de la regulación de los genes bacterianos por las proteínas nucleoides asociadas.
Videos de Conceptos Relacionados
The Nucleosome
15.0K
DNA in a human cell is almost 2m long and it is packed inside a tiny nucleus that is only a few microns in diameter. The level of compaction of DNA inside the nucleus is astonishing. It is organized into several sequentially higher levels of compaction to fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
DNA is wound twice around a protein complex called histone core, that consist of 8 histone proteins. This complex...
15.0K
The Nucleosome Core Particle
12.2K
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
The paradox
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their main responsibility is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. While on the other hand, they must allow polymerase enzymes to access DNA...
12.2K
Nucleosome Remodeling
8.7K
Nucleosomes are the basic units of chromatin compaction. Each nucleosome consists of the DNA bound tightly around a histone core, which makes the DNA inaccessible to DNA binding proteins such as DNA polymerase and RNA polymerase. Hence, the fundamental problem is to ensure access to DNA when appropriate, despite the compact and protective chromatin structure.
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
Nucleosome remodeling complex
Eukaryotic cells have specialized enzymes called ATP-dependent nucleosome remodeling enzymes. These enzymes...
8.7K
Histone Modification
14.6K
The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational modifications such as acetylation, methylation, phosphorylation, and ubiquitination. Particular combinations of these modifications form “histone codes” that influence the chromatin folding and tissue-specific gene expression.
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone...
Acetylation
The enzyme histone acetyltransferase adds acetyl group to the histones. Another enzyme, histone...
14.6K
The Nucleosome
3.9K
Human DNA is almost two meters long. However, it is compressed inside a tiny nucleus measuring only a few microns in diameter. To make this degree of compaction possible, DNA is organized into several sequential levels so that it can fit into such a tiny space. The most compact form of DNA is a chromosome that can be seen under a microscope in a dividing cell.
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
In a chromosome, DNA is wound twice around a protein complex called a histone octamer core, which consists of 8 histone proteins. This...
3.9K
The Nucleosome Core Particle
2.6K
Nucleosomes are the DNA-histone complex, where the DNA strand is wound around the histone core. The histone core is an octamer containing two copies of H2A, H2B, H3, and H4 histone proteins.
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
Nucleosomes, paradoxically, perform two opposite functions simultaneously. On the one hand, their primary aim is to protect the delicate DNA strands from physical damage and help achieve a higher compaction ratio. On the other hand, they must allow polymerase enzymes to access histone-bound DNA during...
2.6K

