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Estabilización de la función del canal de liberación de calcio (receptor de ryanodina) por la proteína de unión FK506
A B Brillantes1, K Ondrias, A Scott
1Department of Medicine, Mount Sinai School of Medicine, New York, New York 10029.
Cell
|May 20, 1994
Resumen
La proteína de unión a FK506 (FKBP12) es crucial para la función del receptor de ryanodina (RyR), modulando los canales de liberación de calcio. Este estudio revela el FKBP12.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Fisiología celular Fisiología celular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- FKBP12 es una isomerasa de prolina expresada en todas partes.
- Su función celular permaneció en gran parte desconocida antes de este estudio.
- Se sabe que FKBP12 interactúa con el receptor de ryanodina (RyR).
Objetivo del estudio:
- Para aclarar la función celular de FKBP12.
- Determinar el papel de FKBP12 en la modulación de la actividad del canal RyR.
- Para investigar el impacto de FKBP12 en la liberación de calcio intracelular.
Principales métodos:
- Coexpresión de RyR y FKBP12 en células de insectos.
- Análisis de las propiedades de encierro de canales RyR.
- Evaluación de la actividad de la isomerasa FKBP12 utilizando FK506 y rapamicina.
Principales resultados:
- FKBP12 aumenta significativamente el número de canales RyR con conductividad completa.
- FKBP12 disminuye la probabilidad de apertura de los canales RyR después de la activación de la cafeína.
- FKBP12 aumenta el tiempo medio de apertura de los canales RyR.
- Los inhibidores FK506 y la rapamicina invirtieron los efectos estabilizadores de FKBP12 en los canales RyR.
Conclusiones:
- El estudio establece la primera función celular natural para FKBP12.
- FKBP12 actúa como un modulador clave de la apertura del canal del receptor de ryanodina.
- El complejo funcional de canales de liberación de Ca2+ incluye intrínsecamente FKBP12.
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