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Measurement of Heme Synthesis Levels in Mammalian Cells
Published on: July 9, 2015
Los orígenes filogenéticos y la evolución adaptativa de los genes de hemoglobina de aves y mamíferos
Nature
|July 15, 1982
Resumen
La evolución de la globina implicó duplicaciones genéticas, lo que condujo a genes embrionarios aviares y mamíferos distintos. La selección natural, no la deriva neutral, impulsó estos cambios en la evolución del gen globina.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- Evolución molecular de la evolución molecular.
- La genómica es la genómica.
Sus antecedentes:
- Rápido crecimiento del aminoácido globina y de la secuencia genética de la hemoglobina.
- El análisis cladístico revela nuevos conocimientos sobre la evolución de los globos.
- Estudios previos sugirieron una evolución independiente de la mioglobina de los antepasados de la globina.
Objetivo del estudio:
- Para investigar los orígenes evolutivos de las aves y mamíferos embrionarios alfa y beta globina genes.
- Determinar el papel de la duplicación génica y la selección natural en la evolución de las globinas.
- Desafiar la hipótesis neutralista de la evolución molecular en las globinas.
Principales métodos:
- Análisis cladístico de secuencias de aminoácidos de globinas.
- Análisis de secuencias de nucleótidos de genes de hemoglobina y pseudogenes.
- Reconstrucción filogenética para inferir eventos de duplicación genética.
Principales resultados:
- Los genes alfa embrionarios de aves (pi) y mamíferos (xi) se originaron en un evento monofilético hace unos 400 millones de años, tras la separación de genes alfa-beta.
- Las duplicaciones independientes de genes beta más tarde produjeron rho embrionario aviar y epsilon embrionario de mamíferos / loci gamma fetales.
- La evidencia apoya la selección natural que actúa sobre los genes duplicados, lo que contradice la visión neutralista.
Conclusiones:
- La evolución de la globina se caracteriza por eventos de duplicación génica que dan forma a las familias de genes en diferentes linajes.
- La evolución de la globina loci embrionaria en aves y mamíferos ocurrió de forma independiente.
- La selección natural jugó un papel importante en la evolución adaptativa de las secuencias de globina, refutando las explicaciones puramente neutralistas.
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