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Kinetochore-localizado PP1-Sds22 parejas segregación cromosómica para la relajación polar
Nelio T L Rodrigues1, Sergey Lekomtsev1, Silvana Jananji2
1MRC Laboratory for Molecular Cell Biology, University College London, Gower Street, London WC1E 6BT, UK.
Nature
|July 14, 2015
Resumen
Una nueva vía de división celular utiliza la fosfatasa PP1-Sds22 para suavizar la corteza celular, lo que permite la segregación cromosómica y la división celular ordenada. Este mecanismo vincula el movimiento de los cromosomas con la polarización cortical.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- Genética La genética.
Sus antecedentes:
- La división celular requiere una coordinación precisa entre la segregación cromosómica y la citoquinesis.
- Los reclutas de Ect2 hacen girar microtúbulos para señalar el montaje y la constricción del anillo de actomiosina.
Objetivo del estudio:
- Identificar nuevas vías de señalización que regulan la división celular.
- Para investigar los mecanismos de acoplamiento de la segregación cromosómica a la división celular.
Principales métodos:
- Estudió la división celular en la proliferación de Drosophila y las células humanas.
- Se han investigado vías de señalización independientes de la formación de surcos, centrosomas y microtúbulos.
Principales resultados:
- Descubrió una vía de señalización paralela que involucra a la PP1 fosfatasa y Sds22.
- Kinetochore-localizado PP1-Sds22 desfosforila las proteínas ezrina/radixina/moesina, suavizando la corteza de las células polares.
- Esta vía facilita el alargamiento de la anafase y la división celular ordenada.
Conclusiones:
- Se identificó una señal de fosfatasa conservada basada en cinetocoros (PP1-Sds22) y un sustrato (ezrina/radixina/moesina).
- Esta vía vincula los movimientos de los cromosomas anafásicos con la polarización cortical.
- Segregación cromosómica de parejas con división celular a través del ablandamiento cortical.
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