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Las chaperonas moleculares activan el receptor de ecdisona de Drosophila, un heterodímero RXR
1Department of Developmental Biology, Stanford University School of Medicine, California 94305, USA.
Cell
|April 25, 2000
Resumen
La hormona esteroide 20-hidroxiyecdisona activa el desarrollo de la Drosophila formando un complejo receptor. Esta activación requiere un complejo de chaperona, con Hsp90 y Hsc70 identificados como componentes clave in vivo dirigidos al receptor de ecdisona (EcR).
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Biología del desarrollo Biología del desarrollo.
- Endocrinología Endocrinología.
Sus antecedentes:
- La hormona esteroide 20-hidroxyecdisona regula el desarrollo de la Drosophila.
- Funciona a través de un heterodímero del receptor de ecdisona (EcR) y el homólogo del receptor de retinoide X (USP).
- La activación de los heterodímeros RXR generalmente no requiere complejos de chaperona.
Objetivo del estudio:
- Para investigar el requisito de los complejos de chaperona para la actividad de unión al ADN EcR/USP.
- Para identificar proteínas específicas dentro del complejo chaperón esencial para la activación de EcR/USP.
- Determinar el papel in vivo de estas proteínas y su objetivo principal dentro del complejo de receptores de ecdisona.
Principales métodos:
- Purificación de seis proteínas individuales del complejo chaperón.
- Ensayos in vitro para probar la suficiencia de las proteínas purificadas para la activación de EcR/USP.
- Estudios in vivo para evaluar la necesidad de Hsp90 y Hsc70 para la actividad del receptor de ecdisona.
Principales resultados:
- La actividad de unión al ADN EcR/USP requiere la activación por un heterocomplejo chaperón.
- Seis proteínas chaperón purificadas fueron suficientes para activar EcR/USP.
- Las proteínas de choque térmico Hsp90 y Hsc70 son esenciales in vivo para la actividad del receptor de ecdisona.
- El receptor de ecdisona (EcR) es el objetivo principal del complejo de chaperona.
Conclusiones:
- Los complejos de Chaperona, anteriormente no vinculados a la activación de heterodímero RXR, son esenciales para la función EcR / USP en Drosophila.
- Las proteínas chaperón específicas, incluidas Hsp90 y Hsc70, juegan un papel crítico en la regulación de la señalización de la hormona esteroide durante el desarrollo.
- EcR es regulado directamente por el complejo de chaperona, destacando un mecanismo conservado en la activación del receptor de esteroides.
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