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El complejo Par dirige la división celular asimétrica mediante la fosforilación de la proteína citoesquelética Lglgl
Jörg Betschinger1, Karl Mechtler, Juergen A Knoblich
1Research Institute of Molecular Pathology, Dr Bohr Gasse 7, 1030 Vienna, Austria.
Nature
|March 12, 2003
Resumen
El complejo de la proteína Par previene la deslocalización del factor determinante del destino celular mediante la fosforilación de las larvas gigantes Lethal (2) (Lgl). Esta fosforilación restringe la actividad de Lgl, asegurando la división celular adecuada y la determinación del destino de las células hijas en los neuroblastos de Drosophila.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología del desarrollo Biología del desarrollo.
- Genética La genética.
Sus antecedentes:
- La asimetría celular es crucial para generar diversos tipos de células durante el desarrollo.
- En los neuroblastos de Drosophila, el complejo de proteína Par establece la polaridad apical-basal, dirigiendo los determinantes del destino celular a las células hijas.
- El mecanismo por el cual el complejo Par logra esta localización direccional de proteínas sigue sin estar claro.
Objetivo del estudio:
- Para dilucidar el mecanismo molecular por el cual el complejo proteico Par dirige los determinantes del destino celular a células hijas específicas durante la mitosis.
- Para investigar el papel de la proteína Lethal (2) larva gigante (Lgl) en este proceso.
Principales métodos:
- Se utilizaron modelos de neuroblastos de Drosophila.
- Empleó experimentos genéticos y bioquímicos.
- Interacciones proteína-proteína investigadas y eventos de fosforilación.
Principales resultados:
- Se demostró que la proteína quinasa C atípica (aPKC), un miembro del complejo Par, fosforila Lgl.
- Se demostró que la fosforilación mediada por aPKC libera Lgl de las asociaciones de membrana y citoesqueleto de actina.
- Se encontró que la Lgl fosforilada impide la localización apical de los determinantes del destino celular, incluido Miranda.
Conclusiones:
- La fosforilación de Lgl por aPKC es un mecanismo clave para restringir la localización determinante del destino celular en el lado basal de los neuroblastos de Drosophila.
- Este evento de fosforilación regula espacialmente la actividad de Lgl, asegurando la correcta segregación de los determinantes para la división celular asimétrica.
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