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Conversión de PrP a una conformación tipo PrPSc autoperpetua en el citosol
1Howard Hughes Medical Institute (HHMI), University of Chicago, Chicago, IL 60637, USA.
Science (New York, N.Y.)
|October 19, 2002
Resumen
La proteína priónica (PrP) puede convertirse en una forma PrPSc asociada a la enfermedad en el citosol. Este mecanismo de conversión celular intrínseco puede explicar el origen de las enfermedades priónicas transmisibles en los mamíferos.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- La bioquímica es la bioquímica.
- Biología celular Biología celular.
Sus antecedentes:
- Las enfermedades priónicas transmisibles están vinculadas a una proteína priónica mal plegada, PrPSc.
- El mecanismo que inicia la formación de PrPSc dentro de las células de mamíferos sigue siendo en gran medida desconocido.
- PrPSc es el agente infeccioso o un componente clave en las enfermedades priónicas.
Objetivo del estudio:
- Para investigar los mecanismos intracelulares de la formación de PrPSc.
- Para determinar si la PrP tiene una capacidad intrínseca de autoconversión dentro de las células de los mamíferos.
Principales métodos:
- Estudió el transporte de proteínas priónicas (PrP) y los cambios conformacionales en el citosol.
- Analizó la formación de agregados amorfos y conformaciones similares a PrPSc.
- Correlacionó la distribución de estas formas con su tasa de aparición.
Principales resultados:
- El PrP transportado retrogradamente desde el retículo endoplasmático formó agregados amorfos y una conformación similar al PrPSc en el citosol.
- La proporción de estas formas dependía de la velocidad de aparición citosólica de PrP.
- Una vez formada, la conformación parecida al PrPSc era estable y autosuficiente.
Conclusiones:
- La proteína priónica posee una capacidad inherente para someterse a la conversión conformacional dentro de las células de los mamíferos.
- Este proceso de conversión intrínseco podría ser el origen del PrPSc. patógeno.
- Los hallazgos ofrecen información sobre la patogénesis de las enfermedades priónicas transmisibles.
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