Evidencia para el nacimiento evolutivo de una nueva vía de determinación del sexo en las abejas melíferas
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Published on: October 5, 2018
Martin Hasselmann1, Tanja Gempe, Morten Schiøtt
1Department of Genetics, Heinrich Heine University Duesseldorf, Universitaetsstrasse 1, 40225 Duesseldorf, Germany.
Nature
|July 3, 2008
Resumen
Las abejas melíferas determinan el sexo a través de la heterocigosidad en el gen del determinante de sexo complementario (csd). Un gen recientemente identificado, el feminizador (fem), actúa aguas arriba de la CDS y es esencial para el desarrollo femenino en las abejas.
Área de la Ciencia:
- Genética La genética.
- Biología del desarrollo Biología del desarrollo.
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- La determinación del sexo de las abejas se basa en la heterocigosidad en el locus del determinante de sexo complementario (csd).
- Los mecanismos moleculares precisos que vinculan las interacciones alélicas de la CDS con el desarrollo sexual siguen sin estar claros.
Objetivo del estudio:
- Identificar nuevos genes involucrados en la vía de determinación del sexo de las abejas.
- Para dilucidar la relación evolutiva entre el feminizador (fem) y los genes de la CDS.
Principales métodos:
- La interferencia de ARN (RNAi) para derribar las variantes específicas de empalme de genes.
- Análisis comparativo de secuencias de genes fem y csd en múltiples especies de abejas.
Principales resultados:
- Se identificó un nuevo gen, el feminizador (fem), 12 kilobases aguas arriba de csd.
- Fem codifica una proteína de tipo SR y se empalma alternativamente, siendo la variante específica de la hembra funcional.
- La eliminación de la variante fem splice específica de las hembras dio como resultado abejas machos.
- La eliminación de las transcripciones de CDS femeninas condujo a la variante fem splice masculina específica.
- El análisis evolutivo sugiere que la CDS se originó en el progenitor femenino a través de la duplicación génica.
Conclusiones:
- El gen fem es un componente crucial de la vía de determinación del sexo de la abeja, necesaria para el desarrollo femenino.
- Fem actúa aguas abajo de la CDS, implementando el cambio en el desarrollo sexual basado en la heterocigosidad de la CDS.
- El origen de la nueva vía de determinación del sexo de las abejas melíferas involucró la duplicación genética y la selección positiva en el CDS.
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