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Analysis of Cap-binding Proteins in Human Cells Exposed to Physiological Oxygen Conditions
Published on: December 28, 2016
El contenido de oxígeno de las proteínas transmembranares en escalas de tiempo macroevolutivas
Claudia Acquisti1, Jürgen Kleffe, Sinéad Collins
1Max Planck Institute for Plant Breeding Research, Carl-von-Linnè-Weg 10, 50829 Köln, Germany. Claudia.Acquisti.1@asu.edu
Nature
|December 22, 2006
Resumen
La compartimentación celular evolucionó a medida que aumentaban los niveles de oxígeno. Las primeras proteínas transmembrana excluían el oxígeno, pero esta restricción se alivió, permitiendo que se desarrollaran proteínas de comunicación más complejas.
Área de la Ciencia:
- Biología evolutiva Biología evolutiva.
- La bioquímica es la bioquímica.
- Biología celular Biología celular.
Sus antecedentes:
- La compartimentación celular es un sello distintivo de la vida eucariota.
- La evolución de la vida temprana coincidió con cambios significativos en los niveles de oxígeno atmosférico.
Objetivo del estudio:
- Investigar la correlación entre la concentración de oxígeno atmosférico y la evolución de la compartimentación celular.
- Para entender el papel de las proteínas transmembrana en este proceso evolutivo.
Principales métodos:
- Predicción bioinformática y caracterización de la topología de proteínas transmembrana en 19 taxones.
- Análisis de correlación entre la topología de las proteínas y las concentraciones históricas de oxígeno atmosférico.
Principales resultados:
- Las proteínas transmembrana probablemente excluyeron el oxígeno en los organismos antiguos.
- Esta restricción que excluye el oxígeno para las proteínas disminuyó a medida que aumentaba el oxígeno atmosférico.
- El tamaño y el número de proteínas transmembrana relacionadas con la comunicación aumentaron con la disminución de las restricciones de oxígeno.
Conclusiones:
- Los niveles de oxígeno atmosférico influyeron en el momento de la evolución de la compartimentación celular.
- La concentración de oxígeno limitó el desarrollo de los dominios de proteínas transmembranales esenciales para la comunicación celular.
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