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CRISPR-Mediated Reorganization of Chromatin Loop Structure
Published on: September 14, 2018
La regulación de la recombinación por la disociación de la cohesión inducida por la transcripción en las repeticiones
Takehiko Kobayashi1, Austen R D Ganley
1National Institute for Basic Biology, SOKENDAI, School of Life Science, 38 Nishigonaka, Myodaijicho, Okazaki, 444-8585 Japan. koba@nibb.ac.jp
Science (New York, N.Y.)
|September 6, 2005
Resumen
Los organismos regulan el número de copias del ADN ribosomal (ADNr) a través de la transcripción de un promotor bidireccional (E-pro). Este proceso implica la disociación de la cohesión, un mecanismo clave para mantener la estabilidad del ADNr y prevenir la amplificación génica.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- Biología celular Biología celular.
Sus antecedentes:
- Los organismos mantienen un número estable de copias de repetición de genes de ARN ribosómico (ADNr) a través de la recombinación.
- La pérdida de repeticiones de ADNr puede desencadenar la amplificación génica.
- La cohesina, un complejo de proteínas, normalmente suprime los cambios en el número de copias del ADNr.
Objetivo del estudio:
- Para dilucidar el mecanismo que regula la amplificación del ADNr.
- Para identificar el papel de la transcripción en el control del número de copias del ADNr.
Principales métodos:
- Investigó la función de un promotor bidireccional no codificante (E-pro) dentro del espaciador de ADNr.
- Se evaluó el impacto de la transcripción E-pro en la unión de la cohesina al ADNr.
- Examinó la regulación de la transcripción E-pro por SIR2 y el número de copia de ADNr.
Principales resultados:
- La amplificación depende de la transcripción del promotor E-pro.
- La transcripción E-pro promueve la disociación de la cohesina del ADNr.
- SIR2 y el número de copias de rDNA regulan la transcripción E-pro.
Conclusiones:
- La disociación de la cohesión inducida por la transcripción es un nuevo mecanismo para regular el número de copias del ADNr.
- Este mecanismo juega un papel crítico en la prevención de la amplificación de genes de ADNr.
- La disociación de la cohesión inducida por la transcripción puede representar un principio general en la regulación de la recombinación.
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