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The Green Monster Process for the Generation of Yeast Strains Carrying Multiple Gene Deletions
Published on: December 15, 2012
Múltiples rondas de especiación asociadas con la pérdida recíproca de genes en levaduras poliploides
Devin R Scannell1, Kevin P Byrne, Jonathan L Gordon
1Smurfit Institute of Genetics, University of Dublin, Trinity College, Dublin 2, Ireland.
Nature
|March 17, 2006
Resumen
La duplicación de todo el genoma en los antepasados de la levadura condujo a la pérdida de genes, impulsando la especiación. Diferentes patrones de pérdida de genes en Saccharomyces cerevisiae, S. castellii y C. glabrata revelan mecanismos de aislamiento reproductivo y emergencia rápida de especies.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- La genómica es la genómica.
- Genética de la levadura genética de la levadura.
Sus antecedentes:
- Un evento compartido de duplicación de todo el genoma ocurrió en el antepasado de Saccharomyces cerevisiae, Saccharomyces castellii y Candida glabrata.
- Los patrones posteriores de pérdida de genes después de esta duplicación varían significativamente entre estas tres especies de levaduras.
Objetivo del estudio:
- Investigar la pérdida diferencial de genes duplicados después de la duplicación del genoma completo en especies de levaduras relacionadas.
- Explorar el papel de la pérdida de genes en la especiación y el aislamiento reproductivo.
- Proponer un modelo unificado de cómo la pérdida de genes impulsa la rápida aparición de especies de levaduras.
Principales métodos:
- Análisis genómico comparativo de los patrones de pérdida de genes en Saccharomyces cerevisiae, Saccharomyces castellii y Candida glabrata.
- Identificación de genes no ortólogos resultantes de la pérdida de genes diferenciales.
- Análisis de la función génica y las tasas evolutivas en los lugares duplicados retenidos.
Principales resultados:
- Se observaron diferencias significativas en la pérdida de genes en el 20% de los loci entre las tres especies.
- El 4-7% de los genes de copia única no eran ortólogos entre especies debido a la pérdida diferencial de pares de genes duplicados.
- Los patrones de pérdida sugieren un mecanismo de Bateson-Dobzhansky-Muller que contribuye al aislamiento reproductivo.
- Los genes duplicados retenidos se enriquecen para la biogénesis ribosómica y los genes de evolución lenta.
Conclusiones:
- La pérdida diferencial de genes después de la duplicación del genoma entero es un factor clave de la especiación de la levadura.
- La pérdida pasiva de genes puede conducir rápidamente al surgimiento de nuevas especies.
- Los patrones observados apoyan un modelo unificado de especiación impulsada por la pérdida de genes en levaduras.
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