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Enfoques a escala genómica para resolver la incongruencia en las filogenias moleculares
Antonis Rokas1, Barry L Williams, Nicole King
1Howard Hughes Medical Institute, Laboratory of Molecular Biology, R. M. Bock Laboratories, University of Wisconsin-Madison, 1525 Linden Drive, Madison, Wisconsin 53706, USA.
Nature
|October 24, 2003
Resumen
Los árboles filogenéticos de un solo gen a menudo entran en conflicto. La combinación de muchos genes, incluso solo 20, resuelve las relaciones de las especies de levadura con alta confianza, mejorando los estudios evolutivos.
Área de la Ciencia:
- Filogenética molecular Filogenética molecular
- La genómica es la genómica.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La incongruencia filogenética de los genes individuales es un gran desafío en la filogenética molecular.
- Resolver las relaciones evolutivas requiere árboles filogenéticos robustos.
Objetivo del estudio:
- Investigar sistemáticamente la incongruencia del árbol genético en las especies de levadura.
- Identificar métodos para resolver señales filogenéticas conflictivas.
Principales métodos:
- Secuencias del genoma de levadura examinadas para genes ortólogos.
- Realizó análisis filogenéticos de genes individuales y conjuntos de genes concatenados.
- Se analizaron conjuntos de datos que van desde genes individuales hasta los 106 genes seleccionados.
Principales resultados:
- Las concatenaciones de genes individuales o pequeños con frecuencia apoyan topologías conflictivas.
- La concatenación de todos los 106 genes produjo un solo árbol de especies de levadura completamente resuelto con el máximo apoyo.
- Un mínimo de 20 genes concatenados proporcionaron una comparable y robusta resolución filogenética.
Conclusiones:
- La incongruencia filogenética es común con datos genéticos limitados.
- La concatenación de un número sustancial de genes, incluso una fracción de un genoma, es crucial para una reconstrucción precisa del árbol de especies.
- Este enfoque tiene implicaciones significativas para la resolución de ramas profundas en el árbol de la vida.
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