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El límite caudal de la expresión de Otx2 posiciona el organizador istmático
V Broccoli1, E Boncinelli, W Wurst
1GSF-Research Centre for Environment and Health, Institute of Mammalian Genetics, Neuherberg, Germany.
Nature
|September 18, 1999
Resumen
El gen homeobox es Otx2
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- La neurociencia es la neurociencia.
- Genética La genética.
Sus antecedentes:
- El gen homeobox Otx2 juega un papel crucial en el desarrollo del tubo neural anterior, con su límite de expresión que define la unión entre el cerebro medio y el cerebro posterior.
- Estudios anteriores demostraron que la inactivación de Otx2 es esencial para el desarrollo dentro de su dominio de expresión.
Objetivo del estudio:
- Investigar si el límite caudal de la expresión de Otx2 es crítico para posicionar el organizador istmático.
- Para determinar si Otx2 influye en el cerebro medio frente a la especificación de destino del cerebro posterior.
Principales métodos:
- La expresión ectópica de Otx2 en el hipotético cerebro posterior anterior usando una estrategia de knock-in en el locus En1.
- Análisis morfológicos e histológicos de cerebros transgénicos adultos.
- Monitoreo de los patrones de expresión de los principales marcadores del desarrollo neuronal (Wnt1, Ephrin-A5, Pax2, Fgf-8, Gbx2).
Principales resultados:
- La descendencia transgénica exhibió ataxia cerebelosa.
- Se observó una reducción significativa en el vermis cerebeloso anterior y un agrandamiento compensatorio del colículo inferior.
- Cambio caudal en la expresión del cerebro medio, el organizador istmático y los marcadores del cerebro posterior en el presunto territorio del cerebro posterior.
Conclusiones:
- El límite caudal de la expresión de Otx2 es suficiente para posicionar el organizador istmático.
- La expresión de Otx2 es fundamental para codificar el destino del cerebro medio caudal dentro del dominio del cerebro medio / posterior.
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