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La cosupresión de transgenes no homólogos en Drosophila implica secuencias endógenas mutuamente relacionadas
M Pal-Bhadra1, U Bhadra, J A Birchler
1Division of Biological Sciences, University of Missouri, Columbia 65211, USA.
Cell
|October 16, 1999
Resumen
Dos genes no homólogos, la deshidrogenasa de alcohol blanco (w-Adh) y Adh-w, desencadenan el silenciamiento de genes a través de la cosupresión. Esta interacción requiere el gen Adh endógeno e implica modificaciones de la cromatina por las proteínas del grupo Polycomb.
Área de la Ciencia:
- Genética La genética.
- Biología Molecular Biología Molecular
- La epigenética es la epigenética.
Sus antecedentes:
- La cosupresión es un fenómeno en el que los genes homólogos desencadenan el silenciamiento de los genes.
- Comprender los mecanismos de silenciamiento de genes es crucial para la investigación genética.
Objetivo del estudio:
- Para investigar la cosupresión entre genes no homólogos, deshidrogenasa de alcohol blanco (w-Adh) y Adh-w.
- Identificar los elementos genéticos y el tiempo de desarrollo involucrados en esta interacción silenciadora.
Principales métodos:
- Utilizando genes de fusión recíproca (w-Adh y Adh-w) para estudiar la cosupresión.
- Empleando la supresión y reintroducción de fragmentos de genes Adh para analizar el reconocimiento de homologías.
- Investigando el papel de la región reguladora Adh y el complejo del grupo Polycomb.
Principales resultados:
- Cosupresión demostrada entre w-Adh y Adh-w, mediada por la secuencia endógena de Adh.
- La eliminación del gen Adh endógeno abolió la interacción de silenciamiento.
- La reintroducción de un fragmento de 8,6 kb Adh restauró el silenciamiento, lo que indica su necesidad.
- Se identificó un segmento no transcrito dentro de la región reguladora Adh como crucial para el reconocimiento de la homología.
- La iniciación del silenciamiento ocurre durante el desarrollo temprano e involucra al complejo del grupo Polycomb.
Conclusiones:
- La cosupresión puede ocurrir entre genes no homólogos si una secuencia homóloga actúa como intermediario.
- Las regiones reguladoras específicas del gen Adh son esenciales para mediar este silenciamiento dependiente de la homología.
- El complejo del grupo Polycomb está implicado en las modificaciones epigenéticas subyacentes al silenciamiento de genes en el desarrollo.
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