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In vivo Application of the REMOTE-control System for the Manipulation of Endogenous Gene Expression
Published on: March 29, 2019
Más allá de la localización: la competencia entre las endonucleasas intrónicas confiere una ventaja selectiva a los
1Department of Biological Sciences, State University of New York at Albany 12222, USA.
Cell
|January 26, 1996
Resumen
Los intrones de los bacteriófagos codifican endonucleasas únicas que dividen cadenas de ADN individuales. Estas enzimas se dirigen sorprendentemente al ADN extraño, lo que confiere una ventaja selectiva al genoma que contiene intrones durante infecciones mixtas.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- Virología Virología.
Sus antecedentes:
- Los bacteriófagos SPO1 y SP82 poseen intrones similares en sus genes de ADN polimerasa.
- Estos intrones codifican nuevas endonucleasas con propiedades distintas.
Objetivo del estudio:
- Para caracterizar las propiedades únicas de las endonucleasas codificadas por las intrones de los bacteriófagos.
- Para investigar los mecanismos de escisión del ADN y las especificidades de dichas enzimas.
- Comprender el papel de estas endonucleasas en las interacciones entre fagos y huéspedes y en la evolución del genoma.
Principales métodos:
- Análisis de la actividad de la endonucleasa codificada intron.
- Ensayos de escisión del ADN utilizando dianas de ADN que contienen intrones e intrones.
- Investigación de la especificidad enzimática hacia el ADN de fagos homólogo y heterólogo.
- Diseño experimental para estudiar infecciones mixtas y análisis de progenie.
Principales resultados:
- Las endonucleasas estudiadas cortan sólo una hebra de ADN, a diferencia de las endonucleasas homing típicas.
- La hendidura se produce a diferentes distancias del sitio de inserción de intrones en objetivos que contienen intrones y en objetivos sin intrones.
- Cada endonucleasa exhibe una preferencia por el ADN del fago heterólogo.
- La endonucleasa codificada por SP82 media la exclusión del intrón y los marcadores SPO1 en infecciones mixtas.
Conclusiones:
- Los intrones de los bacteriófagos codifican las endonucleasas con nuevos mecanismos de escisión del ADN y preferencia por el ADN heterólogo.
- Esta actividad enzimática única proporciona una ventaja selectiva, promoviendo la supervivencia del intrón y el marcador genético asociado.
- Estos hallazgos revelan un nuevo mecanismo de interacción de elementos genéticos y un papel potencial en la evolución del genoma de los fagos.
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