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An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
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Límites fundamentales para la supresión de las fluctuaciones moleculares
Ioannis Lestas1, Glenn Vinnicombe, Johan Paulsson
1Department of Engineering, University of Cambridge, Cambridge CB2 1PZ, UK.
Nature
|September 11, 2010
Resumen
Los sistemas biológicos utilizan retroalimentación negativa para la estabilidad, pero las fluctuaciones moleculares limitan la precisión. El aumento de la precisión requiere exponencialmente más eventos de señalización molecular, desafiando las creencias convencionales sobre la precisión bioquímica.
Área de la Ciencia:
- Biología de Sistemas Biología de Sistemas.
- La biofísica es la biofísica.
- Ingeniería bioquímica Ingeniería bioquímica.
Sus antecedentes:
- Los mecanismos de retroalimentación negativa mejoran la estabilidad en los sistemas biológicos contra las perturbaciones.
- Los bucles de control a nivel molecular están limitados por tasas finitas de nacimiento molecular y eventos de muerte.
Objetivo del estudio:
- Investigar los límites teóricos de la supresión de las fluctuaciones moleculares en sistemas biológicos.
- Desarrollar un marco que fusione la teoría del control, la teoría de la información y la química física para analizar sistemas bioquímicos.
Principales métodos:
- Desarrolló herramientas matemáticas que integraban la teoría del control, la teoría de la información y la química física.
- Formuló restricciones teóricas para la supresión del ruido basadas en las tasas de eventos de señalización.
- Analizó los datos experimentales existentes sobre los procesos reguladores celulares.
Principales resultados:
- Las limitaciones leves en las tasas de nacimiento / muerte moleculares limitan severamente la supresión de las fluctuaciones moleculares.
- La desviación estándar mínima en las escalas de abundancia molecular con la raíz cuártica de los eventos de señalización, haciendo que la alta precisión sea costosa.
- Las células a menudo emplean estrategias de "fuerza bruta", como altas tasas de transcripción, para la supresión del ruido esencial.
Conclusiones:
- La precisión bioquímica está fundamentalmente limitada por el número de eventos de señalización molecular.
- El estudio desafía la comprensión convencional de la precisión en los sistemas biológicos.
- Presenta un nuevo enfoque teórico para el análisis de sistemas biológicos complejos y mal caracterizados.
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