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Evolución dirigida y perfil de especificidad de sustrato de la endonucleasa homing I-SceII
Jeffrey B Doyon1, Vikram Pattanayak, Carissa B Meyer
1Howard Hughes Medical Institute and the Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.
Journal of the American Chemical Society
|February 16, 2006
Resumen
Los científicos diseñaron enzimas con nuevas capacidades de corte de ADN utilizando la evolución de laboratorio. Este avance ofrece nuevas herramientas de edición del genoma y una visión más profunda del reconocimiento del ADN por las nucleasas.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Ingeniería de enzimas Ingeniería de enzimas Ingeniería de enzimas
- La genómica es la genómica.
Sus antecedentes:
- Las enzimas con habilidades específicas de escisión del ADN son valiosas para la manipulación del genoma y la comprensión del reconocimiento del ADN.
- Las endonucleasas homing, como I-SceI, son enzimas que reconocen y cortan secuencias específicas de ADN.
Objetivo del estudio:
- Desarrollar y aplicar un sistema de selección para la evolución de enzimas con características específicas de escisión de ADN hechas a medida.
- Para mejorar la comprensión del reconocimiento de ADN específico de la secuencia por las nucleasas.
- Para diseñar endonucleasas mutantes I-SceI homing con especificidades alteradas de escisión del ADN.
Principales métodos:
- Desarrollo de un eficiente sistema de selección positiva y negativa in vivo para aplicar presión evolutiva.
- Aplicación de la selección in vitro para determinar el perfil de especificidad del sustrato del tipo salvaje I-SceI.
- Utilizando estas herramientas para desarrollar enzimas mutantes I-SceI.
Principales resultados:
- Desarrollo exitoso y aplicación de un sistema de selección in vivo para la evolución de enzimas.
- Caracterización del perfil de especificidad del sustrato I-SceI de tipo silvestre.
- Evolución de las enzimas mutantes I-SceI con especificidades alteradas de la escisión del ADN.
- La enzima mutante más evolucionada exhibió una alta selectividad para una secuencia de ADN mutante objetivo.
Conclusiones:
- Los sistemas de selección desarrollados son efectivos para la evolución de enzimas con nuevas especificidades de escisión del ADN.
- Las enzimas diseñadas pueden lograr una selectividad de escisión del ADN comparable a las enzimas de tipo salvaje.
- Estos avances proporcionan nuevas herramientas para la ingeniería del genoma y el estudio de las interacciones ADN-proteína.
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