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Ablation of a Single Cell From Eight-cell Embryos of the Amphipod Crustacean Parhyale hawaiensis
Published on: March 16, 2014
Los genes Hox y la diversificación de los planes corporales de insectos y crustáceos
Nature
|August 3, 1995
Resumen
Los genes Hox en Artemia (un crustáceo) muestran una expresión superpuesta en el tórax, a diferencia de los insectos donde estos genes especifican segmentos distintos. Esto sugiere una evolución independiente de la segmentación del tronco y la diversificación de la función del gen Hox.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- Biología evolutiva Biología evolutiva.
- Genética La genética.
Sus antecedentes:
- Los crustáceos y los insectos comparten planos corporales segmentados, pero exhiben una evolución independiente de la especialización del segmento troncal.
- Los genes Hox son marcadores genéticos conservados cruciales para comprender el patrón del eje corporal y la identidad del segmento en diversos grupos animales.
Objetivo del estudio:
- Para investigar los patrones de expresión de cuatro genes Hox en el crustáceo branquiópodo Artemia franciscana.
- Para comparar estos patrones con la expresión conocida del gen Hox en insectos para inferir cambios evolutivos en la arquitectura corporal y la función génica.
Principales métodos:
- Análisis comparativo de la expresión génica Hox.
- Examen de cuatro genes Hox específicos (Antp, Ubx, abdA) en la especie Artemia franciscana.
- Comparación de los dominios de expresión génica de Artemia Hox con los de los insectos.
Principales resultados:
- En Artemia, los genes Hox troncales Antp, Ubx y abdA exhiben dominios de expresión que se superponen en gran medida dentro de la región torácica uniforme.
- En contraste, estos mismos genes Hox especifican distintos tipos de segmentos en el tórax y el abdomen de los insectos.
- Estos hallazgos sugieren un proceso de varios pasos para la diversificación funcional del gen Hox.
Conclusiones:
- La evolución de la función del gen Hox involucró diferencias tempranas en la especificidad tisular y la adquisición posterior de roles en la definición de diferencias segmentales.
- El tórax de los branquiópodos puede ser homólogo evolutivamente a toda la región pregenital (torácica y abdominal) del tronco del insecto.
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