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Trypanosome mitochondrial 3' terminal uridylyl transferasa (TUTasa): la enzima clave en la edición de la
Ruslan Aphasizhev1, Sandro Sbicego, Marian Peris
1Department of Microbiology, Immunology, and Molecular Genetics, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Cell
|March 15, 2002
Resumen
Los investigadores purificaron una 3' terminal de ARN uridililtransferasa (TUTasa) de las mitocondrias de Leishmania y clonaron su gen. Esta enzima es crucial para la edición de ARN en Trypanosoma brucei, lo que afecta la viabilidad del parásito cuando se inhibe su expresión.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Parasitología Parasitología.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La edición de ARN es un proceso crucial después de la transcripción en los kinetoplastidos.
- Las 3' terminal RNA uridylyltransferases (TUTases) juegan un papel clave en la edición de ARN mediante la adición de uridinas para guiar a los ARN.
- Comprender la función de la TUTasa es vital para comprender el metabolismo del ARN en estos organismos.
Objetivo del estudio:
- Para purificar y caracterizar el 3' terminal del ARN uridililtransferasa (TUTasa) de Leishmania tarentolae.
- Para clonar y expresar el gen TUTase tanto de Leishmania tarentolae como de Trypanosoma brucei.
- Para investigar la función in vivo y las interacciones de la TUTasa en el Trypanosoma brucei.
Principales métodos:
- Purificación de enzimas de Leishmania tarentolae mitochondria. también conocido como mitocondria.
- La clonación y la expresión de genes en sistemas procariotas.
- Estudios in vivo utilizando la interferencia del ARN (RNAi) en el Trypanosoma brucei.
- Los ensayos de coprecipitación utilizan antisuero anti-TUTasa.
Principales resultados:
- Se purificó y caracterizó la TUTasa específica de adición de 3' U dependiente de A Mg(2+).
- La enzima existe in vivo como aproximadamente 500 kDa oligómeros y aproximadamente 700 kDa complejos.
- Se descubrió que la TUTasa interactúa con las ligasas de ARN y los ARN guía.
- La inhibición de la expresión de la TUTasa a través del ARNi condujo a la desregulación de la edición del ARN y afectó la viabilidad del parásito.
Conclusiones:
- La TUTasa purificada es enzimáticamente activa y es específica para la adición de 3' U.
- La TUTasa funciona en múltiples formas complejas in vivo, interactuando con otros factores clave de procesamiento de ARN.
- La TUTasa es esencial para la edición del ARN y la supervivencia del parásito en Trypanosoma brucei, destacando su potencial como objetivo terapéutico.
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