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La función del erizo sónico en las aletas de los condrichtianos y la evolución del patrón de patrón de los apéndices
Randall D Dahn1, Marcus C Davis, William N Pappano
1Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois 60637, USA.
Nature
|December 26, 2006
Resumen
La regulación del gen Sonic hedgehog (Shh) está profundamente conservada en la evolución de los apéndices emparejados de los vertebrados. Los chondrichthyans comparten la expresión Shh y los patrones de función con los peces con aletas de rayos y los tetrápodos, revelando mecanismos genéticos conservados.
Área de la Ciencia:
- Biología del desarrollo evolutivo Biología del desarrollo evolutivo
- La genómica comparada es una genómica comparada.
- Paleontología de los vertebrados.
Sus antecedentes:
- Se conoce la genética del desarrollo de las extremidades de los tetrápodos, pero el ensamblaje evolutivo y la función de los vertebrados basales siguen sin estar claros.
- Se pensaba que los chondrichthyans, vertebrados primitivos con apéndices emparejados, tenían un esqueleto de apéndice independiente de Sonic hedgehog (Shh).
- Esto contrasta con los peces con aletas de rayos y los tetrápodos, lo que sugiere caminos evolutivos divergentes.
Objetivo del estudio:
- Para investigar la conservación evolutiva de la función del gen Sonic hedgehog (Shh) en los vertebrados basales.
- Para aclarar el papel de Shh en el desarrollo del apéndice chondrichthyan y sus implicaciones evolutivas.
- Para comparar la regulación Shh a través de los principales linajes de vertebrados.
Principales métodos:
- Análisis comparativo de los patrones de expresión génica de Shh en los condríctios.
- Identificación y caracterización de los elementos de ADN reguladores específicos del apéndice Shh.
- Estudios funcionales que evalúan el papel de Shh en el patrón de los apéndices.
Principales resultados:
- Chondrichthyans exhiben patrones conservados de la expresión del apéndice Shh.
- Se identificaron secuencias similares de ADN reguladoras específicas del apéndice Shh en condrictos, peces con aletas de rayos y tetrápodos.
- La evidencia sugiere que Shh juega un papel funcional conservado en el patrón del apéndice de los condrichtianos.
Conclusiones:
- La función del erizo sónico (Shh) en el desarrollo de los apéndices se conserva profundamente a través de la filogenia de los vertebrados.
- La evolución de los mecanismos reguladores de Shh probablemente contribuyó a los principales cambios morfológicos durante la evolución de los apéndices.
- Los chondrichthyans comparten mecanismos fundamentales de patronaje dependientes de Shh con otros vertebrados con mandíbula.
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