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Neonatal Subventricular Zone Electroporation
Published on: February 11, 2013
Un receptor nuclear huérfano activado por los embarazos define una nueva vía de señalización de esteroides
S A Kliewer1, J T Moore, L Wade
1Department of Molecular Endocrinology, Glaxo Wellcome Research and Development, Research Triangle Park, North Carolina 27709, USA.
Cell
|March 7, 1998
Resumen
Los investigadores descubrieron el receptor X pregnano (PXR), un nuevo receptor nuclear activado por varios esteroides. La PXR influye en la homeostasis de la hormona esteroide y el esterol, lo que sugiere una nueva vía de señalización.
Área de la Ciencia:
- Endocrinología Endocrinología.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las hormonas esteroides regulan los procesos celulares críticos a través de los receptores nucleares.
- La comprensión de los nuevos receptores nucleares es clave para descifrar las vías de señalización complejas.
Objetivo del estudio:
- Identificar y caracterizar un nuevo receptor nuclear huérfano involucrado en la acción de la hormona esteroide.
- Investigar la activación y las implicaciones funcionales de este nuevo receptor.
Principales métodos:
- Identificación de un nuevo receptor nuclear huérfano, el receptor pregnano X (PXR).
- Análisis de la activación de la PXR por esteroides naturales y sintéticos.
- Examen de la activación específica de las isoformas de PXR (PXR.1 y PXR.2).
- Evaluación del efecto de la pregnenolona 16alfa-carbonitrilo en PXR.1 y la expresión génica aguas abajo.
Principales resultados:
- Descubrimiento del receptor X pregnano (PXR), activado por diversos esteroides, incluidas la pregnenolona y la progesterona.
- Identificación de dos isoformas de PXR (PXR.1 y PXR.2) con activación diferencial de esteroides.
- La pregnenolona 16alfa-carbonitrilo activa selectivamente el PXR.1, induciendo las hidroxilasas esteroideas CYP3A.
- Evidencia de la modulación de la PXR en la biosíntesis de esteroles y ácidos biliares in vivo.
Conclusiones:
- El receptor X pregnano (PXR) representa un nuevo receptor nuclear que media la señalización de la hormona esteroide.
- La PXR juega un papel en la regulación de la homeostasis de la hormona esteroide y el esteroide.
- Este descubrimiento abre caminos para comprender nuevas vías en la regulación metabólica.
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