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Quantitative Comparison of cis-Regulatory Element (CRE) Activities in Transgenic Drosophila melanogaster
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La selección natural y el origen del jingwei, un gen funcional quimérico procesado en Drosophila
1Section of Genetics, University of California, Davis 95616.
Science (New York, N.Y.)
|April 2, 1993
Resumen
Un gen procesado en Drosophila, anteriormente un pseudogén, evolucionó en un nuevo gen funcional llamado jingwei. El origen de este gen implicó la captura de ADN de otro gen, lo que demuestra el papel de la selección natural en la evolución de nuevos genes.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Genética molecular genética molecular.
- La genómica es la genómica.
Sus antecedentes:
- El origen de nuevos genes es un proceso fundamental en la evolución.
- Comprender el origen de los genes requiere examinar tanto los mecanismos moleculares como la dinámica de la población.
- Un gen procesado de Drosophila alcohol deshidrogenasa (Adh), inicialmente considerado un pseudógeno, ofreció un modelo único para estudiar la formación de nuevos genes.
Objetivo del estudio:
- Investigar los eventos moleculares y la dinámica poblacional involucrados en el origen de un nuevo gen funcional.
- Para analizar la trayectoria evolutiva de un gen quimérico formado por la captura de secuencias de ADN no relacionadas.
- Determinar el papel de la selección natural en la aparición y posterior evolución de nuevos genes.
Principales métodos:
- Análisis de secuencia del gen Adh procesado y su integración en un nuevo locus genético.
- Comparación de patrones de expresión génica entre el nuevo gen quimérico y su gen padre Adh.
- Evaluación de la tasa de evolución molecular del nuevo gen.
Principales resultados:
- Una secuencia de ARN mensajero Adh procesada se incorporó a un nuevo gen funcional, llamado jingwei, al capturar exones e intrones aguas arriba de un gen no relacionado.
- El nuevo gen quimérico, jingwei, exhibió patrones de expresión distintos en comparación con su gen padre Adh.
- La tasa de evolución molecular difería entre el gen jingwei y el gen Adh original.
- La evidencia sugiere que la selección natural jugó un papel en el origen y la evolución del gen jingwei.
Conclusiones:
- El estudio demuestra una vía plausible para el nacimiento de nuevos genes a través de la captura de exones y la formación de genes quiméricos.
- El gen jingwei sirve como un estudio de caso para comprender la interacción de la innovación molecular y la selección natural en la configuración de los genomas.
- Nuevos genes funcionales pueden surgir a partir de elementos genéticos previamente no funcionales a través de la recombinación y el nuevo regulador.
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