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TMEM16F forma un canal catiónico activado por Ca2+ requerido para la mezcla de lípidos en las plaquetas durante la
Huanghe Yang1, Andrew Kim, Tovo David
1Department of Physiology, Howard Hughes Medical Institute, University of California, San Francisco, 94143, USA.
Cell
|October 2, 2012
Resumen
La proteína TMEM16F es crucial para la coagulación de la sangre, actuando como un canal iónico activado por el calcio esencial para la mezcla de lípidos en las plaquetas. Su disfunción causa trastornos hemorrágicos e impacta la trombosis, destacando su papel en la salud cardiovascular.
Área de la Ciencia:
- Biología Molecular Biología Molecular
- La biofísica es la biofísica.
- Hematología Hematología.
Sus antecedentes:
- La asimetría lipídica de la membrana es vital para la coagulación de la sangre.
- La deficiencia de TMEM16F está relacionada con el síndrome de Scott y la alteración de la mezcla lipídica dependiente de calcio.
- Las proteínas de la familia TMEM16 incluyen canales de cloruro activados por calcio (CaCC).
Objetivo del estudio:
- Para investigar el papel de TMEM16F en la coagulación sanguínea y la función plaquetaria.
- Para caracterizar la actividad del canal iónico de TMEM16F.
- Para identificar los determinantes moleculares de la selectividad del canal TMEM16F.
Principales métodos:
- Generación y análisis de ratones knockout TMEM16F.
- Evaluación de los defectos de sangrado y modelos de trombosis arterial.
- Registros electrofisiológicos de TMEM16F. expresado heterológicamente.
- Mutagénesis dirigida al sitio para detectar la función del canal.
Principales resultados:
- Los ratones nocaut TMEM16F muestran defectos de sangrado y protección contra la trombosis arterial.
- Las plaquetas de ratones knockout muestran una exposición deficiente a la fosfatidilserina dependiente del calcio y una actividad procoagulante.
- La expresión heteróloga de TMEM16F produce una corriente de catión no selectivo (SCAN) activado por calcio de pequeña conductividad, no un CaCC.
- Los canales TMEM16F-SCAN son permeables a los cationes, incluido el Ca2+, y están cerrados por el calcio y el voltaje.
- Un residuo poroso específico influye en la selectividad catión versus anión para los canales TMEM16F y TMEM16A.
Conclusiones:
- TMEM16F funciona como un canal catiónico activado por calcio crítico para la actividad de la plaqueta scramblase durante la coagulación sanguínea.
- TMEM16F es esencial para mantener la asimetría lipídica de la membrana y la función procoagulante en las plaquetas.
- Comprender las propiedades del canal TMEM16F proporciona información sobre el síndrome de Scott y los trastornos de la coagulación.
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