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Tracking Morphogenetic Tissue Deformations in the Early Chick Embryo
Published on: October 17, 2011
Distorsión permanente del sistema posicional del embrión de Xenopus por una breve perturbación temprana de la
Nature
|January 2, 1986
Resumen
El desarrollo temprano de las ranas establece un plan corporal utilizando un sistema posicional. Interrumpir este sistema con la gravedad revela su breve ventana reguladora y registros de patrones permanentes.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- Embriología Embriología.
- Biología celular Biología celular.
Sus antecedentes:
- La formación del plano corporal de los animales se basa en un sistema posicional y respuestas locales.
- Los primeros productos genéticos en Drosophila sugieren mecanismos conservados en los vertebrados.
- Comprender el sistema posicional de los vertebrados es crucial para la biología del desarrollo.
Objetivo del estudio:
- Investigar la naturaleza fisiológica del sistema posicional en embriones de vertebrados.
- Perturbar el sistema posicional para comprender sus propiedades reguladoras y sus mecanismos de registro.
- Prueba de hipótesis con respecto a los "plasmas" determinantes o los mecanismos basados en la difusión en la formación de patrones de Xenopus.
Principales métodos:
- Experimentalmente perturbando el sistema posicional en embriones de Xenopus.
- Utilizando reordenamientos impulsados por la gravedad para entrar en conflicto con los reordenamientos auto-organizados.
- Observando los efectos de la perturbación en la formación de patrones corporales en las larvas.
Principales resultados:
- El sistema posicional en Xenopus especifica la posición del cuerpo temprano en el desarrollo (aprox. 2 horas). durante el día.
- El sistema tiene un breve intervalo de propiedades reguladoras; las perturbaciones durante este tiempo conducen a registros de patrones permanentes.
- Los reordenamientos inducidos por la gravedad entran en conflicto con la autoorganización, lo que resulta en patrones corporales anormales.
Conclusiones:
- El sistema posicional de Xenopus sugiere un sistema de registro estructural o mecánico, no un gradiente de difusión.
- Los resultados contradicen los modelos basados en 'plasmas' determinantes o difusión molecular de largo alcance para la formación de patrones primarios.
- El sistema posicional exhibe plasticidad, pero establece registros permanentes después de una ventana crítica temprana.
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