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Visualization of DNA Repair Proteins Interaction by Immunofluorescence
Published on: June 26, 2020
Rad6-Rad18 media una respuesta SOS eucariota mediante la ubiquitinación de la abrazadera del punto de control 9-1-1
1Department of Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, S7N 5E5, Canada.
Cell
|May 20, 2008
Resumen
El complejo Rad6-Rad18 coordina las respuestas al daño del ADN en la levadura, similar a la respuesta SOS bacteriana. Regula la transcripción génica y las vías de reparación del ADN a través de la ubiquitinación de proteínas.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Los eucariotas carecen de una respuesta global bien definida al daño del ADN similar a la respuesta SOS bacteriana.
- Se sabe que el complejo de ubiquitinación Rad6-Rad18 está involucrado en la reparación del ADN.
Objetivo del estudio:
- Para investigar el papel del complejo Rad6-Rad18 en la respuesta al daño del ADN de los eucariotas.
- Para determinar si Rad6-Rad18 influye en la transcripción genética global después del daño del ADN.
Principales métodos:
- Genética de la levadura y técnicas de biología molecular.
- Análisis de los cambios en la expresión génica en respuesta al daño del ADN.
- Ensayos de ubiquitinación y estudios de interacción con las proteínas.
Principales resultados:
- El complejo Rad6-Rad18 es esencial para la regulación al alza de la transcripción inducida por el daño del ADN de numerosos genes de levadura.
- Rad6-Rad18 cataliza la monoubiquitinación de Rad17 (una subunidad del complejo 9-1-1) en K197.
- La ubiquitinación de Rad17 es crucial para la fosforilación eficiente de Rad53 y la activación del punto de control del daño en el ADN.
Conclusiones:
- El complejo Rad6-Rad18 actúa como un regulador clave de la expresión génica global durante la respuesta al daño del ADN en la levadura, análogo a la respuesta SOS bacteriana.
- Este complejo coordina múltiples vías de respuesta al daño del ADN mediante la ubicuidad de las abrazaderas de ADN PCNA y 9-1-1.
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