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El polarisoma es necesario para la segregación y el transporte retrógrado de agregados proteicos
Beidong Liu1, Lisa Larsson, Antonio Caballero
1Department of Cell and Molecular Biology, University of Gothenburg, Medicinaregatan 9C, 413 90 Göteborg, Sweden.
Cell
|February 10, 2010
Resumen
La levadura Sir2p establece la asimetría del envejecimiento celular al retener las proteínas dañadas en las células madre. Las proteínas clave como Bni1p y Myo2p segregan agregados durante la división celular, con las células hijas limpiando el daño a través del flujo polarizado.
Área de la Ciencia:
- Biología celular Biología celular.
- Investigación sobre el envejecimiento Investigación sobre el envejecimiento.
- Genética de la levadura Genética de la levadura
Sus antecedentes:
- El envejecimiento celular implica asimetría, con proteínas dañadas retenidas en las células madre.
- Las sirtuinas, como Sir2p en la levadura, juegan un papel crucial en esta asimetría de edad.
- La comprensión de los mecanismos de segregación de agregados proteicos es clave para la investigación del envejecimiento.
Objetivo del estudio:
- Para dilucidar las interacciones genéticas globales de SIR2 en la levadura en ciernes.
- Para identificar la maquinaria molecular responsable de segregar los agregados de proteínas durante la división celular.
- Investigar el papel de Sir2p en las funciones citoesqueléticas y la polaridad celular.
Principales métodos:
- Análisis global de la red de interacción genética de SIR2.2.
- Identificación de las proteínas clave involucradas en la segregación de agregados proteicos.
- Análisis de los defectos citosqueléticos y de polaridad en las células sir2Δ.
Principales resultados:
- El polarisoma, la formina Bni1p y la miosina Myo2p son esenciales para segregar los agregados de proteínas.
- Las células hijas pueden eliminar el daño a través de un flujo polarizado dependiente del polarisoma y la tropomiosina en las células madre.
- El papel de Sir2p en la función citoesquelética está relacionado con el plegamiento de actina comprometido por la chaperonina CCT en las células sir2Δ.
Conclusiones:
- Los mecanismos de polaridad, que involucran a proteínas como Bni1p y Myo2p, son críticos para controlar el daño celular y la asimetría del envejecimiento.
- Los hallazgos apoyan modelos en los que la polaridad evolucionó para prevenir la senescencia clonal mediante la creación de linajes celulares de envejecimiento y rejuvenecimiento distintos.
- Sir2p influye en la integridad del citoesqueleto, afectando la gestión de los agregados proteicos y el envejecimiento celular.
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