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Measuring G-protein-coupled Receptor Signaling via Radio-labeled GTP Binding
Published on: June 9, 2017
La subunidad de la proteína G Galpha13 se une a la integrina alfaIIbbeta3 y media la señalización "de afuera hacia
Haixia Gong1, Bo Shen, Panagiotis Flevaris
1Department of Pharmacology, University of Illinois at Chicago, 835 South Wolcott Avenue, Room E403, Chicago, IL 60612, USA.
Science (New York, N.Y.)
|January 16, 2010
Resumen
Las integrinas funcionan como receptores acoplados Galpha13 no canónicos. Esta interacción regula directamente la RhoA, impactando en la difusión celular y la dinámica de retracción.
Área de la Ciencia:
- Biología celular Biología celular.
- La señalización molecular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- Las integrinas median la adhesión celular y transmiten señales que influyen en el comportamiento celular.
- El mecanismo preciso de la señalización integrina exterior-interior sigue siendo incompletamente entendido.
Objetivo del estudio:
- Para dilucidar el mecanismo de la señalización exterior-interior de la integrina.
- Para identificar las interacciones moleculares directas involucradas en la transducción de señales de integrina.
Principales métodos:
- Investigó la unión directa de Galpha13 al dominio citoplasmático de la integrina beta3.
- Interferencia utilizada de la expresión de Galpha13 y fragmentos inhibidores de Galpha13.
- Evaluación de la activación de la proteína quinasa c-Src y la pequeña guanosina trifosfatasa RhoA.
Principales resultados:
- Galpha13 se une directamente al dominio citoplasmático de la integrina beta3.
- La unión de ligandos al alfaIIbbeta3 y la carga de GTP de Galpha13 promueven la interacción Galpha13-integrina.
- La interferencia con la unión a Galpha13-integrina inhibió la activación de Src y estimuló RhoA, lo que condujo a una reducción de la propagación celular y una mayor retracción.
Conclusiones:
- Las integrinas funcionan como receptores acoplados Galpha13 no canónicos.
- Esta interacción proporciona un mecanismo para la regulación dinámica de RhoA.
- Los hallazgos ofrecen nuevos conocimientos sobre la adhesión celular mediada por integrina y las vías de señalización.
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