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La miosina polarizada produce hijas de tamaño desigual durante la división celular asimétrica
Guangshuo Ou1, Nico Stuurman, Michael D'Ambrosio
1The Howard Hughes Medical Institute and the Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA. gou@ibp.ac.cn
Science (New York, N.Y.)
|October 9, 2010
Resumen
El tamaño de la división celular y el destino de las células hijas están controlados por la actividad de la miosina. En C. elegans, la acumulación asimétrica de miosina conduce a una división celular desigual, con las células más pequeñas sometidas a apoptosis.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología del desarrollo Biología del desarrollo.
- Genética La genética.
Sus antecedentes:
- El posicionamiento asimétrico del huso típicamente precede a la citocinesis, produciendo células hijas con destinos distintos.
- El tamaño desigual de la célula puede surgir incluso con un eje centrado, lo que sugiere mecanismos alternativos.
- El linaje de neuroblastos de Caenorhabditis elegans Q proporciona un modelo para el estudio de la división celular asimétrica.
Objetivo del estudio:
- Investigar el mecanismo que genera células hijas de diferentes tamaños en el linaje de neuroblastos Q de C. elegans, a pesar de un eje centrado.
- Determinar el papel de la miosina II en la mediación de la división celular asimétrica y el destino posterior de las células hijas.
Principales métodos:
- Observación de la división celular en el linaje de neuroblastos Q de C. elegans.
- Cuantificación de la acumulación de miosina II durante la división.
- La inactivación láser asistida por cromóforo (CALI) para inhibir selectivamente la actividad de la miosina anterior.
Principales resultados:
- La división de los neuroblastos Q produjo células hijas desiguales, con la célula anterior más pequeña sometida a apoptosis.
- Se observó un aumento de la acumulación de miosina II en la porción anterior de la célula en división.
- La inactivación parcial de la miosina II anterior dio lugar a una división más simétrica y la supervivencia de la célula hija anterior.
Conclusiones:
- Las fuerzas contráctiles asimétricas mediadas por la miosina II, en lugar del posicionamiento del husillo, pueden impulsar la determinación desigual del tamaño celular.
- El equilibrio de la actividad de la miosina dicta el tamaño de las células hijas y el destino posterior, incluida la supervivencia o la apoptosis.
- Este estudio revela un nuevo mecanismo para generar asimetría celular y controlar los resultados del desarrollo.
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