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La activación dopaminérgica y ligando-independiente de los receptores de la hormona esteroide
R F Power1, S K Mani, J Codina
1Department of Cell Biology, Baylor College of Medicine, Houston, TX 77030.
Science (New York, N.Y.)
|December 13, 1991
Resumen
Los receptores de la hormona esteroide pueden activarse sin un ligando, ya que la dopamina imita a la progesterona. Un residuo específico de serina en el receptor de progesterona de pollo (cPR) es clave para esta activación independiente del ligando.
Área de la Ciencia:
- Endocrinología Molecular La Endocrinología Molecular
- La neuroendocrinología en neuroendocrinología.
- Reglamento genético Reglamento genético.
Sus antecedentes:
- Los receptores de hormonas esteroides tradicionalmente requieren la unión de ligandos para la activación y la regulación de la transcripción génica.
- La activación de los receptores generalmente se considera dependiente únicamente del evento de unión de ligando.
- La evidencia emergente sugiere vías alternativas para la activación del receptor.
Objetivo del estudio:
- Para investigar la activación ligando-independiente de los receptores de la hormona esteroide.
- Para explorar el papel de la dopamina como un activador no tradicional del receptor de progesterona.
- Para identificar los mecanismos moleculares específicos que subyacen a la activación del receptor mediada por dopamina.
Principales métodos:
- Experimentos in vitro con el receptor de progesterona de pollo (cPR).
- Evaluación de la translocación del receptor del citoplasma al núcleo.
- Análisis mutacional de residuos específicos de aminoácidos dentro del cPR.
Principales resultados:
- La dopamina, un neurotransmisor, activó la RCP de una manera independiente de los ligandos.
- La dopamina imitaba el efecto de la progesterona al inducir la translocación de la RCP al núcleo.
- Se identificó un residuo específico de serina como esencial para la activación dependiente de la dopamina, pero no para la activación dependiente de la progesterona.
Conclusiones:
- Los receptores de la hormona esteroide pueden ser activados a través de vías independientes del ligando.
- La dopamina actúa como un agonista funcional para el receptor de progesterona, destacando el diálogo cruzado entre los sistemas de señalización.
- Residuos específicos de aminoácidos median distintas vías de activación, ofreciendo información sobre la regulación de los receptores.
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