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Updated: Jul 7, 2026
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Isolation of Mesenchymal Stem Cells from Human Alveolar Periosteum and Effects of Vitamin D on Osteogenic Activity of Periosteum-derived Cells
Published on: May 4, 2018
Jun-Fos y los receptores para las vitaminas A y D reconocen un elemento de respuesta común en el gen de la
R Schüle1, K Umesono, D J Mangelsdorf
1Howard Hughes Medical Institute, Salk Institute, La Jolla, California 92037.
Cell
|May 4, 1990
Resumen
El elemento de respuesta de vitamina D en el gen de la osteocalcina también responde al ácido retinoico. Este acoplamiento cruzado de factores de transcripción revela nuevos conocimientos sobre la regulación génica por la vitamina A y la vitamina D.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- Reglamento genético Reglamento genético.
- Endocrinología Endocrinología.
Sus antecedentes:
- El gen de la osteocalcina humana contiene un elemento de respuesta de la vitamina D (VDRE).
- La vitamina D y el ácido retinoico son moléculas de señalización cruciales involucradas en varios procesos celulares.
Objetivo del estudio:
- Investigar el papel del VDRE en la mediación de la respuesta del ácido retinoico.
- Para identificar los factores de transcripción involucrados en la regulación de la expresión génica de la osteocalcina.
Principales métodos:
- Ensayos de unión in vitro utilizando el receptor de ácido retinoico expresado por bacterias (RAR).
- Estudios in vivo que involucran la transfección de vectores de expresión de RAR en células cultivadas.
- Análisis de la interacción del sitio AP-1 con el complejo Jun-Fos y los efectos de la cotransfección.
Principales resultados:
- El VDRE confiere respuesta al ácido retinoico, lo que demuestra el acoplamiento cruzado.
- El receptor del ácido retinoico (RAR) se une a la secuencia VDRE in vitro.
- La co-transfección con Jun y Fos suprimió la transcripción basal e indujo ácido retinoico y vitamina D3.
Conclusiones:
- Diferentes clases de factores de transcripción pueden reconocer secuencias reguladoras comunes (acoplamiento cruzado).
- El sitio AP-1 dentro del VDRE es un sitio de reconocimiento central para múltiples factores.
- Este hallazgo proporciona nuevos conocimientos sobre el diálogo cruzado entre las vías de señalización de la vitamina A y la vitamina D.
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