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Isolation of Translating Ribosomes Containing Peptidyl-tRNAs for Functional and Structural Analyses
Published on: February 25, 2011
Síntesis selectiva de proteínas por ribosomas con un túnel de salida obstruido por fármacos
Krishna Kannan1, Nora Vázquez-Laslop, Alexander S Mankin
1Center for Pharmaceutical Biotechnology, University of Illinois at Chicago, 900 S. Ashland Avenue, Chicago, IL 60607, USA.
Cell
|October 30, 2012
Resumen
Los antibióticos macrolides dirigidos al túnel de salida del ribosoma no bloquean toda la síntesis de proteínas. En cambio, permiten la síntesis de proteínas específicas basadas en su estructura, remodelando el proteoma celular.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Biología Estructural Biología estructural.
- La bioquímica es la bioquímica.
Sus antecedentes:
- El túnel de salida de polipéptidos del ribosoma es crucial para el plegamiento de proteínas nacientes y es un objetivo para los antibióticos macrólidos.
- Se cree que los macrolides inhiben la síntesis de proteínas obstruyendo este túnel.
- El impacto preciso de los macrólidos en la producción de proteínas celulares sigue siendo incompletamente entendido.
Objetivo del estudio:
- Para investigar el efecto de los antibióticos macrólidos en la función del ribosoma y la síntesis de proteínas.
- Para determinar si los ribosomas ligados al fármaco pueden sintetizar polipéptidos específicos.
- Para aclarar el papel de la estructura de la proteína en la navegación por el túnel de salida del polipéptido obstruido.
Principales métodos:
- Utilizando técnicas de biología estructural para analizar los ribosomas ligados a fármacos.
- Empleando ensayos bioquímicos para monitorear la síntesis de proteínas en presencia de macrolides.
- Analizar las características estructurales de los polipéptidos sintetizados por los ribosomas afectados.
Principales resultados:
- Los ribosomas ligados a fármacos pueden sintetizar un subconjunto distinto de polipéptidos celulares.
- La capacidad de un polipéptido para atravesar el túnel obstruido está determinada por su estructura.
- Mientras que algunas proteínas pasan por alto la detención inicial, su síntesis puede detenerse más tarde en el alargamiento; otras completan la traducción.
- Los antibióticos macrolides alteran selectivamente el proteoma celular en lugar de bloquear globalmente la síntesis de proteínas.
Conclusiones:
- El túnel de salida ribosomal exhibe propiedades discriminatorias, influenciadas por efectores de pequeñas moléculas como los macrolides.
- Los antibióticos macrolides no causan un cierre completo de la síntesis de proteínas, sino más bien remodelar el proteoma.
- Comprender estos mecanismos es vital para el desarrollo de terapias dirigidas con antibióticos.
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