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Engineering Artificial Factors to Specifically Manipulate Alternative Splicing in Human Cells
Published on: April 26, 2017
Una familia de proteínas eucariotas altamente conservada que posee propiedades de factor de liberación de la cadena
L Frolova1, X Le Goff, H H Rasmussen
1Department of Molecular Biology, University of Aarhus, Denmark.
Nature
|December 15, 1994
Resumen
Los científicos identificaron una familia de proteínas conservadas, eRF1, crucial para terminar la síntesis de proteínas en los eucariotas. Este descubrimiento aclara la función de los factores de liberación eucarióticos (RF) en la terminación de la traducción.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Genética La genética.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La terminación de la síntesis de proteínas está regulada por los codones de parada y los factores de liberación (RF).
- Se conoce la estructura de las RF procarióticas y mitocondriales, pero la estructura de la RF eucariótica (eRF) no está clara.
- Se reconoce una única RF eucariota (eRF), pero su identidad y función requieren aclaración.
Objetivo del estudio:
- Identificar y caracterizar el factor de liberación eucariota (eRF) involucrado en la terminación de la traducción.
- Investigar la similitud estructural y funcional de potenciales ERF en diferentes especies eucariotas.
- Para confirmar el papel de las proteínas identificadas en la terminación de la síntesis de proteínas.
Principales métodos:
- Análisis de secuencias para identificar familias de proteínas conservadas en eucariotas.
- Expresión heteróloga de proteínas candidatas en levadura y E. coli.
- Ensayos de factor de liberación in vitro para probar la actividad de las proteínas.
- Análisis funcional de Saccharomyces cerevisiae sup45 (sup1) en su traducción.
Principales resultados:
- Se identificó una familia conservada de proteínas relacionadas, designadas eRF1, en eucariotas inferiores y superiores.
- Las proteínas eRF1 humanas y de Xenopus laevis se expresaron, purificaron y demostraron actividad en ensayos de RF in vitro.
- La proteína sup45 (sup1) de Saccharomyces cerevisiae, parte de la familia eRF1, está involucrada en la supresión de la traducción.
- Se observó una alta conservación de las secuencias de aminoácidos dentro de la familia eRF1.
Conclusiones:
- La familia de proteínas eRF1 está directamente involucrada en la terminación de la traducción en los eucariotas.
- Las proteínas eRF1 se conservan estructural y funcionalmente en diversos organismos eucariotas.
- Este hallazgo resuelve la pregunta de larga data con respecto a la identidad y función de los factores de liberación eucariotas.
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