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El ensamblaje de ESCRT-III y la absisión citokinética son inducidos por la liberación de tensión en el puente
Julie Lafaurie-Janvore1, Paolo Maiuri, Irène Wang
1Institut Curie, CNRS UMR 144, Paris, France.
Science (New York, N.Y.)
|March 30, 2013
Resumen
La abscisión de la división celular se desencadena por una liberación de tensión en el puente intercelular, no por fuerzas de tracción. Esta liberación de tensión activa el ensamblaje ESCRT-III, lo que lleva a la fisión de la membrana y la separación celular.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- La citocinesis, la etapa final de la división celular, da como resultado dos células hijas conectadas por un puente intercelular.
- El proceso de absisión, cortando este puente, implica eventos moleculares conocidos, pero carece de un desencadenante definido.
- La fase de conexión prolongada durante la citoquinesis sugiere que está en juego un mecanismo regulador.
Objetivo del estudio:
- Para identificar el desencadenante de la abscisión, el paso final en la división celular.
- Investigar el papel de las fuerzas físicas en la regulación del tiempo de la separación celular.
- Para dilucidar los eventos moleculares que siguen a la liberación de la tensión en el puente intercelular.
Principales métodos:
- Utilizó imágenes de células vivas para observar las conexiones de las células hijas y la dinámica del puente intercelular.
- Aplicaba fuerzas mecánicas controladas a las células hijas para manipular la tensión en el puente.
- Investigó el montaje y la localización de los componentes de la ESCRT-III en respuesta a los cambios de tensión.
Principales resultados:
- Las fuerzas de tracción ejercidas por las células hijas paradójicamente prolongaron la conexión de puente intercelular.
- Se encontró que una liberación de tensión en el puente intercelular induce la abscisión.
- La liberación de tensión inició el ensamblaje de la ESCRT-III, que precede a la fisión de la membrana.
Conclusiones:
- La tensión física, específicamente su liberación, actúa como un disparador crucial para la abscisión.
- La maquinaria ESCRT-III se activa al liberarse la tensión, mediando la fisión de la membrana.
- Este mecanismo de detección de tensión permite que las células hijas permanezcan conectadas hasta que se asienten adecuadamente, ayudando a la organización del tejido y la morfogénesis.
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