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La diversidad alélica y la genealogía en el locus de autoincompatibilidad de las solanáceas
A D Richman1, M K Uyenoyama, J R Kohn
1Department of Biology, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA.
Science (New York, N.Y.)
|August 30, 1996
Resumen
El tamaño efectivo de la población (Ne) en dos especies solanáceas varió significativamente, revelando distintas dinámicas históricas de la población. Equilibrar la selección en el locus de autoincompatibilidad ayuda a entender los eventos de especiación y la historia de la población.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Genética de la población Genética de la población.
- Ciencias de las plantas Ciencias de las plantas.
Sus antecedentes:
- El locus de autoincompatibilidad (S) en las plantas con flores es un modelo de polimorfismo extremo mantenido por la selección de equilibrio.
- Comprender el tamaño efectivo de la población (Ne) es crucial para inferir historias demográficas y procesos evolutivos.
- La selección de equilibrio puede preservar la diversidad genética e influir en la especiación, particularmente la especiación de evento fundador.
Objetivo del estudio:
- Para estimar el tamaño efectivo de la población reciente y a largo plazo (Ne) en dos especies solanáceas.
- Investigar el impacto de la dinámica histórica de la población en la diversidad del S-locus.
- Para evaluar el papel de los cuellos de botella en la especiación de eventos fundadores utilizando loci bajo la selección de equilibrio.
Principales métodos:
- Análisis de la diversidad de alelos S en dos especies de plantas solanáceas.
- Estimación del tamaño efectivo de la población reciente y a largo plazo (Ne) basado en datos del alelo S.
- Comparación de las historias demográficas inferidas de los datos del S-locus.
Principales resultados:
- Las estimaciones recientes de Ne difieren en un orden de magnitud entre las dos especies, en correlación con las diferencias ecológicas.
- Una especie mostró evidencia de restricción histórica de la población a pesar de un gran reciente Ne.
- Las otras especies carecían de evidencia de cuellos de botella severos durante millones de años.
Conclusiones:
- La diversidad del S-locus proporciona información sobre las historias demográficas contrastantes de las especies relacionadas.
- Los cuellos de botella de la población son significativos en la especiación de eventos fundadores.
- Los loci bajo la selección de equilibrio son valiosos para evaluar la frecuencia de la especiación de eventos fundadores.
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