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Detection of Protein Ubiquitination
Published on: August 19, 2009
La ubiquitilación inducida por UV de la proteína XPC mediada por el complejo UV-DDB-ubiquitina ligasa
Kaoru Sugasawa1, Yuki Okuda, Masafumi Saijo
1Cellular Physiology Laboratory, RIKEN Discovery Research Institute, Japan Science and Technology Agency, Wako, Saitama 351-0198, Japan. sugasawa@riken.jp
Cell
|May 11, 2005
Resumen
La ubiquitilación del complejo proteico del grupo C de xeroderma pigmentosum (XPC) es crucial para la reparación del ADN. Este proceso, dependiente de la proteína de unión al ADN dañada por los rayos UV (UV-DDB), facilita la transferencia del daño al ADN inducido por los rayos UV para la reparación por escisión de nucleótidos (NER).
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Mecanismos de reparación del ADN.
- Respuesta celular a la radiación UV de las células
Sus antecedentes:
- El complejo de xeroderma pigmentosum grupo C (XPC) es vital para reconocer el daño del ADN genómico durante la reparación por escisión de nucleótidos (NER).
- El complejo de proteínas de unión al ADN dañadas por la luz ultravioleta (UV-DDB) está implicado en el reconocimiento del daño inducido por NER, pero su papel exacto y su relación con XPC no están claros.
Objetivo del estudio:
- Investigar el papel de la ubicuitación en la interacción entre XPC y UV-DDB durante la reparación del ADN.
- Para dilucidar las consecuencias funcionales de la ubicuidad de XPC en la unión al ADN y el reconocimiento de lesiones.
Principales métodos:
- Estudió los efectos de la irradiación UV en la proteína XPC en las células de mamíferos.
- Interacciones físicas investigadas entre XPC y UV-DDB utilizando ensayos bioquímicos.
- Se analizó el impacto de la poliubiquitilación en las propiedades de unión al ADN de XPC y UV-DDB.
- Evaluó el requisito de ubicuidad para el NER libre de células de fotoproductos inducidos por UV.
Principales resultados:
- XPC se somete a una ubicuidad reversible después de la irradiación UV, dependiendo de la actividad funcional UV-DDB.
- XPC y UV-DDB interactúan físicamente y son poliubiquitulados por una ligasa de ubiquitina asociada a UV-DDB.
- La poliubiquitilación modifica las características de unión al ADN tanto del XPC como del UV-DDB.
- La ubiquitilación es esencial para el NER libre de células de los fotoproductos inducidos por UV (6-4) cuando el UV-DDB se une a la lesión.
Conclusiones:
- La ubiquitación es un mecanismo de regulación crítico en la vía NER.
- Los hallazgos sugieren que la ubicuidad media la transferencia de lesiones de ADN dañadas por rayos UV de UV-DDB a XPC.
- Este estudio aclara la interacción entre UV-DDB, XPC y ubicuidad en el procesamiento de daño al ADN inducido por rayos UV.
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