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La dinámica de la actina impulsa la reorganización de la membrana y la escisión en la endocitosis independiente de la
Winfried Römer1, Léa-Laetitia Pontani, Benoît Sorre
1Institut Curie, Centre de Recherche, CNRS UMR, Paris, France. winfried.roemer@curie.fr
Cell
|February 25, 2010
Resumen
La reorganización de la actina impulsa la escisión de los túbulos de membrana inducidos por la toxina de Shiga, un proceso dependiente del colesterol pero independiente de la dinamina. Esto sugiere un mecanismo físico para la constricción de la membrana durante la endocitosis.
Área de la Ciencia:
- Biología celular Biología celular.
- El tráfico de membranas.
- La biofísica es la biofísica.
Sus antecedentes:
- La escisión de la membrana es crucial para la formación de vesículas durante la endocitosis.
- Existen mecanismos de escisión dependientes de dinamina e independientes, siendo este último poco conocido.
- La endocitosis independiente de la clatrina implica una escisión independiente de la dinamina.
Objetivo del estudio:
- Para dilucidar el mecanismo de la escisión de la membrana independiente de la dinamina en la endocitosis inducida por la toxina de Shiga.
- Para investigar el papel del colesterol y la actina en este proceso de escisión.
- Para explorar las fuerzas físicas que impulsan la constricción de los túbulos de la membrana.
Principales métodos:
- El agotamiento celular de los componentes de actina (Arp2).
- Estudios de reorganización de la membrana dependientes del colesterol. estudios de reorganización de la membrana dependientes del colesterol.
- Experimentos de modelo de membrana basados en liposomas.
- Ensayos de endocitosis inducida por la toxina de Shiga.
Principales resultados:
- La reorganización de la membrana dependiente del colesterol precede a la escisión de los túbulos de la toxina de Shiga.
- La actina desencadena la escisión al inducir la reorganización de la membrana.
- La formación de la cáscara de actina en los liposomas induce la escisión del túbulo dependiente del colesterol y independiente de la dinamina.
- La aparición de túbulos aumenta con el agotamiento de Arp2.
Conclusiones:
- La reorganización de la membrana desencadenada por la actina, impulsada por las fuerzas de los límites del dominio, media la escisión de los túbulos de la toxina Shiga.
- Este mecanismo físico opera independientemente o en sinergia con la actividad de pinchazo.
- El colesterol juega un papel clave en la regulación de la escisión mediada por actina.
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