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Secuencias de proteínas del mastodonte y el tiranosaurio rex reveladas por espectrometría de masas
John M Asara1, Mary H Schweitzer, Lisa M Freimark
1Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA. jasara@bidmc.harvard.edu
Science (New York, N.Y.)
|April 14, 2007
Resumen
La espectrometría de masas recuperó con éxito secuencias de proteínas de los huesos del antiguo mastodonte y del tiranosaurio rex. Esta técnica ofrece una forma novedosa de estudiar la evolución de especies extintas cuando el ADN no está disponible.
Área de la Ciencia:
- La paleoproteómica es la paleoproteómica.
- Paleontología Molecular Paleontología molecular
- Biología evolutiva Biología evolutiva.
Sus antecedentes:
- Los huesos fosilizados pueden contener biomoléculas como proteínas y ADN.
- Estas moléculas ofrecen información sobre las relaciones evolutivas de las especies extintas.
- Obtener material genético antiguo a menudo es un desafío debido a la degradación.
Objetivo del estudio:
- Para investigar la viabilidad de extraer secuencias de proteínas de huesos antiguos utilizando espectrometría de masas.
- Para analizar la estabilidad de las proteínas y la integridad de la secuencia en especímenes excepcionalmente viejos.
- Establecer la espectrometría de masas como una herramienta viable para estudiar la evolución de los taxones antiguos que carecen de datos genómicos.
Principales métodos:
- Utilizó espectrometría de masas de alta resolución para analizar muestras de huesos.
- Se obtuvieron secuencias de proteínas de un mastodonte extinto (Mammut americanum) de entre 160.000 y 600.000 años de edad.
- Se recuperaron con éxito secuencias de péptidos de un fósil de tiranosaurio rex de 68 millones de años de antigüedad.
Principales resultados:
- Se identificaron secuencias de proteínas únicas tanto de mastodontes como de ejemplares de T. rex.
- Demostró una notable estabilidad de los enlaces péptidos en las proteínas del antiguo Tyrannosaurus rex.
- Los patrones de fragmentación de péptidos proporcionaron datos de secuencia confiables para el análisis evolutivo.
Conclusiones:
- La espectrometría de masas es una herramienta poderosa para recuperar secuencias de proteínas de fósiles antiguos.
- Este método permite el estudio de la historia evolutiva de especies en las que el ADN no se conserva.
- La estabilidad de las proteínas antiguas, incluso de los dinosaurios, abre nuevas vías en la paleoproteómica.
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