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Una vía molecular que determina la asimetría izquierda-derecha en la embriogénesis de pollitos
M Levin1, R L Johnson, C D Stern
1Department of Genetics, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|September 8, 1995
Resumen
Los investigadores identificaron una cascada molecular que determina la asimetría izquierda-derecha en embriones de pollo. Los genes clave como Sonic hedgehog (Shh) muestran expresión asimétrica, influyendo en el desarrollo de los órganos y el establecimiento de ejes corporales.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- La embriogénesis es la embriogénesis.
- Genética molecular La genética molecular.
Sus antecedentes:
- La especificación del eje embrionario temprano (antero-posterior, dorso-ventral) es bien entendida.
- La base celular y molecular de la asimetría izquierda-derecha (LR) en la morfogénesis animal sigue siendo en gran medida desconocida.
Objetivo del estudio:
- Investigar los mecanismos moleculares subyacentes a la asimetría izquierda-derecha (LR) en el desarrollo del embrión de pollo.
- Para identificar genes clave y sus patrones de expresión involucrados en el establecimiento de diferencias LR.
Principales métodos:
- Se examinaron los patrones de expresión de los receptores de activina IIa, Sonic hedgehog (Shh) y cNR-1 en embriones de pollo.
- Interacciones genéticas analizadas durante y después de la gastrulación.
- Manipuló la proteína activina y la expresión Shh para observar los efectos en el sitio del corazón.
Principales resultados:
- Expresión asimétrica identificada de los receptores de activina IIa, Shh y cNR-1 durante y después de la gastrulación.
- Demostraron una vía reguladora secuencial entre estos genes.
- Se demostró que la alteración de la activina o la lateralidad Shh afecta el sitio cardíaco, lo que confirma su papel en la determinación de la LR.
Conclusiones:
- Una cascada de asimetría molecular que involucra a los receptores de activina IIa, Shh y cNR-1 dicta la asimetría morfológica LR en embriones de pollo.
- Esta vía es crucial para establecer asimetrías fundamentales en el plano corporal durante el desarrollo.
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