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Isolation of Intermediate Filament Proteins from Multiple Mouse Tissues to Study Aging-associated Post-translational Modifications
Published on: May 18, 2017
Proteínas de filamento intermedio en estructuras no filamentosas: desintegración transitoria e inclusión de proteínas
Cell
|August 1, 1982
Resumen
Durante la mitosis, los filamentos intermedios en el riñón y las células HeLa se deshacen en hilos y forman agregados de proteínas. Estas estructuras se reorganizan de nuevo en filamentos durante la telofase.
Área de la Ciencia:
- Biología celular Biología celular.
- Dinámica del citoesqueleto Dinámica del citoesqueleto
- Organización de las proteínas Organización de las proteínas
Sus antecedentes:
- Los filamentos intermedios, compuestos por citoqueratina y vimentina, forman la red estructural de la célula.
- Estos filamentos experimentan cambios significativos durante la división celular (mitosis).
Objetivo del estudio:
- Para investigar las transformaciones estructurales de los filamentos intermedios durante la mitosis.
- Para caracterizar la naturaleza de los agregados de proteínas de filamento intermedios formados durante la mitosis.
Principales métodos:
- Microscopia de células epiteliales renales bovinas cultivadas y células HeLa humanas.
- Análisis de células intactas y citoesqueletos aislados durante varias etapas mitóticas.
- Observación de células sometidas a mitosis normal y detención mitótica inducida por colcemida.
Principales resultados:
- Los haces de filamentos intermedios se deshacen en hilos similares a protofilamentos de 2-4 nm durante la mitosis.
- Las proteínas citokeratina y vimentina forman agregados esferoidales distintos (0,2-1,5 micras) que contienen partículas granulares (5-16 nm).
- Estos agregados coexisten con filamentos residuales en algunas células, y los filamentos se restablecen en la telofase.
Conclusiones:
- Las proteínas de filamento intermedio pueden formar estructuras distintas a los filamentos, como granos y agregados, durante la mitosis.
- Factores celulares específicos promueven el desenmarañamiento de filamentos y la reorganización de proteínas en agregados en ciertos tipos de células.
- Las células epiteliales y de carcinoma pueden poseer mecanismos para modular y reorganizar filamentos intermedios.
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