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Production of Xenopus tropicalis Egg Extracts to Identify Microtubule-associated RNAs
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Autoorganización de los asteros de microtúbulos inducidos en extractos de huevo de Xenopus por Ran Ran unido al GTP
T Ohba1, M Nakamura, H Nishitani
1Department of Molecular Biology, Graduate School of Medical Science, Kyushu University, Maidashi Higashi-ku, Fukuoka 812-8582, Japan.
Science (New York, N.Y.)
|May 21, 1999
Resumen
El factor de intercambio de nucleótidos de guanina RCC1 es esencial para la formación de asteros de microtúbulos. Ran GTP, regulado por RCC1, impulsa la autoorganización de los microtúbulos, lo que requiere la actividad de la dineína.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- RCC1 (Regulador de la condensación cromosómica 1) es el único factor de intercambio de nucleótidos de guanina para Ran.
- Ran es una Ras-como pequeña GTPasa crucial para varios procesos celulares.
- La formación de asteros de microtúbulos es vital para la división celular y el transporte intracelular.
Objetivo del estudio:
- Para investigar el papel de RCC1 y su efector aguas abajo Ran en la formación de asteros de microtúbulos.
- Para determinar el estado específico ligado a nucleótidos de Ran (GTP o GDP) que promueve la organización de los microtúbulos.
- Para dilucidar la participación de la dineína en la autoorganización de los microtúbulos mediada por Ran.
Principales métodos:
- Utilizados extractos de huevo de Xenopus detenidos en la meiosis II.
- RCC1 empobrecido de extractos de huevo para evaluar su necesidad.
- Formación inducida de aster de microtúbulos utilizando Ran GTP o Ran GDP en extractos empobrecidos con RCC1.
- Evaluó el requisito de actividad de diineína en la organización de microtúbulos observada.
Principales resultados:
- La actividad de intercambio de nucleótidos RCC1 fue indispensable para la formación de asteros de microtúbulos.
- Ran GTP, pero no Ran GDP, indujo la autoorganización espontánea de asteros de microtúbulos en extractos empobrecidos con RCC1.
- El proceso de autoorganización de los microtúbulos inducido por Ran-GTP requería la actividad de la dineína.
Conclusiones:
- Ran GTP es un regulador clave de la formación de la red de microtúbulos.
- La función de RCC1 en el intercambio de nucleótidos para Ran es crítica para iniciar la organización de microtúbulos.
- La dineína juega un papel crucial en el ensamblaje mediado por Ran de los ásteres de microtúbulos.
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