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Evolución reguladora convergente y pérdida de vuelo en aves paleognáticas
Timothy B Sackton1,2, Phil Grayson2,3, Alison Cloutier2,3
1Informatics Group, Harvard University, Cambridge, MA, USA. tsackton@g.harvard.edu sedwards@fas.harvard.edu.
Science (New York, N.Y.)
|April 6, 2019
Resumen
La evolución convergente de la pérdida de vuelo de las aves está impulsada por cambios en el ADN regulador, no en los genes codificadores de proteínas. Este hallazgo pone de relieve la importancia de la regulación genética en la formación de rasgos complejos durante la evolución.
Área de la Ciencia:
- Biología evolutiva
- La genómica
- Biología del desarrollo
Sus antecedentes:
- La evolución convergente de rasgos complejos plantea preguntas sobre los impulsores moleculares.
- Comprender si las regiones codificadoras o reguladoras de proteínas impulsan la convergencia es clave.
Objetivo del estudio:
- Investigar las bases moleculares de la evolución convergente en la pérdida de vuelo entre las aves paleognato.
- Determinar las funciones relativas de los genes codificadores de proteínas frente a las regiones reguladoras en la evolución convergente.
Principales métodos:
- Se realizaron análisis filogenómicos, de desarrollo y epigenómicos en 11 genomas de paleognath.
- Análisis bayesiano de 284.001 elementos no codificantes conservados, incluidos los potenciadores identificados por estados de cromatina abiertos.
- Examinó la expresión génica en el desarrollo de las extremidades delanteras de aves no voladoras.
Principales resultados:
- La evolución convergente de las regiones reguladoras, no de los genes codificadores de proteínas, es frecuente en las vías de pérdida de vuelo.
- Identificó 2355 aceleraciones independientes en los elementos reguladores a través de linajes de paleognaths sin vuelo.
- Estos cambios regulatorios tienen consecuencias funcionales para la expresión génica en el miembro anterior en desarrollo.
Conclusiones:
- Las regiones reguladoras juegan un papel sustancial en el paisaje genómico de la convergencia morfológica en las aves.
- Los cambios moleculares convergentes en los potenciadores son un factor importante de convergencia fenotípica, particularmente en la pérdida de vuelo.
- El estudio proporciona información sobre los mecanismos genéticos que subyacen a las adaptaciones evolutivas.
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