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11:07
Biochemical Reconstitution of Steroid Receptor•Hsp90 Protein Complexes and Reactivation of Ligand Binding
Published on: September 21, 2011
Los receptores de glucocorticoides y progesterona se unen a los mismos sitios en dos promotores regulados
Nature
|February 21, 1985
Resumen
Los receptores de hormonas esteroideas, al igual que el receptor de glucocorticoides, reconocen secuencias similares de ADN en los promotores de genes. Esto sugiere que los elementos reguladores compartidos controlan la expresión génica de múltiples hormonas.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Endocrinología Endocrinología.
- Genética La genética.
Sus antecedentes:
- El receptor glucocorticoide (GR) del hígado de rata interactúa con las secuencias de ADN cerca del promotor del virus del tumor mamario de ratón (MMTV), crucial para la inducción hormonal en los estudios de transferencia génica.
- Se identifican secuencias similares de ADN en el gen humano de la metalotioneína IIA y el gen de la lisozima de pollo, que responde al estrógeno, la progesterona y los andrógenos.
Objetivo del estudio:
- Investigar las similitudes estructurales entre los elementos reguladores del ADN reconocidos por diferentes receptores de hormonas esteroideas.
- Para determinar si las secuencias de promotores compartidos median las respuestas de expresión génica a múltiples hormonas esteroides.
Principales métodos:
- Experimentos de transferencia génica para identificar secuencias de promotores MMTV reconocidas por el hígado de rata GR.
- Experimentos de microinyección que implican la eliminación de pares de bases específicos en el promotor de lisozima de pollo.
- Los ensayos de huella de exonucleasa III utilizan hígado de rata purificado GR y receptor de progesterona (PR) del útero de conejo.
Principales resultados:
- La eliminación de 44 pares de bases (-208 a -164) en el promotor de lisozima de pollo condujo a una pérdida coordinada de la expresión génica dependiente de la progesterona y los glucocorticoides.
- El hígado de rata purificado GR y el útero de conejo PR produjeron huellas de exonucleasa III similares o superpuestas en las regiones promotoras de MMTV y lisozima de pollo.
Conclusiones:
- Los elementos reguladores de las diferentes hormonas esteroides pueden compartir similitudes estructurales.
- Estos hallazgos sugieren un mecanismo común para la regulación génica mediada por la hormona esteroide a través de secuencias de reconocimiento de ADN compartidas.
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