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Regulación del calendario de la escisión del elemento transponible durante el desarrollo del maíz
Science (New York, N.Y.)
|June 22, 1990
Resumen
Los elementos transponibles (ET) exhiben un tiempo regulado en el desarrollo del grano de maíz. Los factores genéticos del huésped parecen controlar el momento de la escisión del transposón durante la proliferación de las células aleuronas.
Área de la Ciencia:
- Genética y Biología Molecular.
- Biología del desarrollo Biología del desarrollo.
- Ciencias de las plantas Ciencias de las plantas.
Sus antecedentes:
- Los elementos transponibles (ET) son secuencias móviles de ADN que pueden alterar la estructura del genoma y la expresión génica.
- La actividad TE específica del tejido demuestra regulación espacial y del desarrollo, pero la regulación temporal es menos comprendida.
- Comprender el tiempo de TE es crucial para descifrar su papel en la evolución del genoma y el desarrollo del organismo.
Objetivo del estudio:
- Investigar la regulación temporal de la actividad del elemento transponible (TE) durante el desarrollo del grano de maíz.
- Para determinar si el tiempo de escisión de TE está controlado por factores genéticos del huésped durante la ontogenia.
Principales métodos:
- Variación cuantificada inducida por TE en la capa de aleurona del maíz, un tejido unicelular.
- Tamaños de sector asignados a divisiones celulares específicas durante el desarrollo de aleuronas.
- Estudió las tres principales familias de TE (Mu, Spm, Ac/Ds) en dos loci genéticas.
Principales resultados:
- La frecuencia de escisión de TE varió dramáticamente (hasta 30 veces) durante la proliferación de aleurona.
- Se observaron cambios consistentes en el tiempo de escisión en las tres familias de TE estudiadas.
- Estos patrones temporales ocurrieron en eventos específicos de división celular conservados.
Conclusiones:
- El momento de la escisión del elemento transponible durante el desarrollo del maíz no es aleatorio.
- Es probable que los factores genéticos del huésped jueguen un papel importante en el control de la actividad temporal de las ET.
- Esto sugiere una regulación coordinada de la dinámica TE por el genoma del huésped durante el desarrollo.
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