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Control materno de la determinación del sexo haplodiploide en la avispa Nasonia
Eveline C Verhulst1, Leo W Beukeboom, Louis van de Zande
1Evolutionary Genetics, Centre for Ecological and Evolutionary Studies, University of Groningen, Netherlands.
Science (New York, N.Y.)
|May 1, 2010
Resumen
En los insectos Hymenoptera que carecen del locus csd, el desarrollo femenino depende del gen del transformador Nasonia vitripennis (Nvtra). La impronta materna evita la transcripción de Nvtra cigótica masculina, mientras que la fertilización desencadena el empalme específico de la hembra para el desarrollo femenino.
Área de la Ciencia:
- Entomología Entomología.
- Genética La genética.
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- Los himenópteros exhiben una determinación del sexo haplodiploide, donde los machos se desarrollan a partir de huevos no fertilizados y las hembras de los fertilizados.
- La abeja Apis mellifera utiliza el locus complementario de determinación del sexo (CSD) para la determinación del sexo.
- Los mecanismos de determinación del sexo en Hymenoptera que carecen del locus csd siguen siendo en gran medida desconocidos.
Objetivo del estudio:
- Para dilucidar el mecanismo de determinación del sexo en la avispa parásita Nasonia, que carece del locus csd.
- Identificar los factores genéticos y las vías reguladoras que controlan el desarrollo femenino en Nasonia.
Principales métodos:
- Investigó el papel del gen del transformador de Nasonia vitripennis (Nvtra) en la determinación del sexo.
- Se analizó la contribución materna de ARNm y la transcripción cigótica de Nvtra.
- Examinó el proceso de empalme específico femenino regulado por Nvtra.
Principales resultados:
- Nasonia carece de un locus de CDS, lo que indica una vía alternativa de determinación del sexo.
- El ARNm maternal de Nvtra y la transcripción zigótica de Nvtra son cruciales para el desarrollo femenino.
- Nvtra autorregula su propio empalme para producir transcripciones específicas de las mujeres.
- La impronta materna impide la transcripción de Nvtra cigótica en óvulos no fertilizados, lo que lleva al desarrollo masculino.
Conclusiones:
- El sistema de determinación del sexo de Nasonia se basa en la regulación génica de Nvtra, no en el locus del CDS.
- El desarrollo femenino está controlado por la impronta materna y la autorregulación Nvtra cigótica del empalme.
- Este estudio revela un nuevo mecanismo de determinación del sexo en Hymenoptera.
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