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Química de activación potencialmente prebiótica compatible con la copia de ARN no enzimática
Stephanie J Zhang1, Daniel Duzdevich2, Jack W Szostak1,2
1Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States.
Journal of the American Chemical Society
|August 16, 2020
Resumen
Este estudio introduce un nuevo método para activar nucleótidos de ácido ribonucleico (ARN) utilizando la activación formadora de puentes. Este avance apoya la copia continua de ARN no enzimática, crucial para comprender el origen de la vida.
Área de la Ciencia:
- El origen de los estudios biológicos
- Química prebiótica
- Evolución molecular
Sus antecedentes:
- La replicación no enzimática del ácido ribonucleico (ARN) es un mecanismo propuesto para la propagación temprana de la información genética.
- La copia continua de ARN requiere la activación de nucleótidos in situ, un desafío que la química prebiótica no había logrado previamente.
- La química cianosulfídica ofrece una ruta potencial para la activación de nucleótidos prebióticos, pero su integración con la copia de ARN no fue probada.
Objetivo del estudio:
- Demostrar una nueva vía para la activación de nucleótidos de ARN compatible con la replicación no enzimática.
- Investigar la aplicación de la química cianosulfúrica prebiótica a la copia continua del ARN.
- Para permitir simulaciones más realistas de la propagación temprana del ARN.
Principales métodos:
- Desarrollo de una nueva vía de activación de puentes.
- Activación química de nucleótidos de ARN bajo condiciones de cianosulfuro.
- Demostración de la copia de ARN no enzimática dirigida por la plantilla utilizando nucleótidos activados.
Principales resultados:
- Una nueva vía genera selectivamente el intermediario de dinucleótido con puente de imidazolio requerido.
- Activación exitosa de los nucleótidos de ARN de una manera compatible con la copia no enzimática.
- Demostración de la copia continua de ARN impulsada por la activación in situ de los nucleótidos.
Conclusiones:
- La activación formadora de puentes proporciona un mecanismo viable para la replicación continua del ARN no enzimático.
- Esta vía une la química prebiótica con los requisitos para la propagación temprana del material genético.
- Los hallazgos facilitan un modelado más preciso de los orígenes de la vida basados en el ARN.
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