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Las estructuras helicoidales de la ESCRT-III son desmontadas por el VPS4
Suman Lata1, Guy Schoehn, Ankur Jain
1Unit for Virus Host Cell Interaction, UMR 5233 UJF (Université Joseph Fourier)-EMBL (European Molecular Biology Laboratory)-CNRS, 6 rue Jules Horowitz, 38042 Grenoble Cedex 9, France.
Science (New York, N.Y.)
|August 9, 2008
Resumen
Los complejos de clasificación endosómica necesarios para el transporte (ESCRT) de las proteínas CHMP2A y CHMP3 forman tubos helicoidales que facilitan el brote de la membrana. La ATPasa VPS4 del tipo AAA desmonta estas estructuras, controlando la formación de vesículas.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- Los complejos de clasificación endosómica necesarios para la maquinaria de transporte (ESCRT) son cruciales para los eventos de remodelación de la membrana.
- Las proteínas ESCRT median procesos como la formación de cuerpos multivesiculares, el brote viral y la citocinesis.
Objetivo del estudio:
- Investigar el ensamblaje in vitro y la función de las proteínas CHMP2A y CHMP3 de la ESCRT-III.
- Para aclarar el papel de VPS4 en el desmontaje de las estructuras mediadas por ESCRT.
Principales métodos:
- Ensayos de ensamblaje in vitro de las proteínas CHMP2A y CHMP3.
- Análisis de la copolimerización CHMP2A/CHMP3 y la unión a la membrana.
- Estudios in vitro de desmontaje mediado por VPS4 de los tubos CHMP2A/CHMP3.
Principales resultados:
- CHMP2A y CHMP3 se autoensamblan en tubos helicoidales con sitios de interacción de la membrana externa.
- La copolimerización de CHMP2A y CHMP3 mejora la orientación de la membrana.
- VPS4 se une al interior de estos tubos y los desmonta a través de la hidrólisis de ATP.
Conclusiones:
- Las estructuras helicoidales de CHMP pueden formarse dentro de los cuellos vesiculares en ciernes, impulsando la escisión de la membrana.
- VPS4 actúa como un regulador, controlando el desmontaje de estas estructuras para completar la remodelación de la membrana.
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