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Comprehensive Profiling of Dopamine Regulation in Substantia Nigra and Ventral Tegmental Area
Published on: August 10, 2012
Interacciones aromático-aromáticas y azufre-π funcionalmente importantes en el receptor de dopamina D2
Kristina N-M Daeffler1, Henry A Lester, Dennis A Dougherty
1Division of Chemistry & Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA.
Journal of the American Chemical Society
|August 18, 2012
Resumen
Los residuos aromáticos en los receptores de dopamina forman un microdominio que conecta las hélices 3, 5 y 6. Esta estructura es crucial para traducir la unión de la dopamina en la activación del receptor.
Área de la Ciencia:
- La bioquímica es la bioquímica.
- Biología Molecular Biología Molecular
- Farmacología Farmacología.
Sus antecedentes:
- La estructura cristalina del receptor de dopamina D3 revela un grupo de residuos aromáticos conservados.
- Esta región conecta el sitio de unión con el movimiento helicoidal intracelular.
- Comprender este microdominio es clave para la función del receptor de dopamina.
Objetivo del estudio:
- Para investigar el papel funcional de los residuos aromáticos en el receptor de dopamina D2.
- Para sondear las interacciones dentro de un microdominio conservado que conecta las hélices 3, 5 y 6.
- Para dilucidar el mecanismo de activación del receptor de dopamina.
Principales métodos:
- Análisis del ciclo de doble mutante.
- Mutagénesis de aminoácidos no naturales.
- Fluoración progresiva de las cadenas laterales aromáticas.
Principales resultados:
- Se observó un acoplamiento funcional significativo entre los residuos en diferentes hélices (C3.36/W6.48, T3.37/S5.46, F5.47/F6.52).
- Las tendencias de fluoración sugieren importantes interacciones electrostáticas y aromáticas-aromáticas.
- Evidencia de una interacción de azufre-π entre C3.36 y W6.48.8.
Conclusiones:
- Un microdominio compacto de residuos en las hélices 3, 5 y 6 actúa como una barrera para la unión de la dopamina.
- Este microdominio traduce la unión extracelular de dopamina en movimientos intracelulares.
- El microdominio conservado probablemente mantiene su conformación durante la activación del receptor.
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