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Pak funciona aguas abajo de Dock para regular la guía de los axones fotorreceptores en Drosophila
1Howard Hughes Medical Institute, Department of Biological Chemistry, School of Medicine, University of California, Los Angeles 90095, USA.
Cell
|July 10, 1999
Resumen
La quinasa activada por Drosophila p21 (Pak) es esencial para guiar los axones de las células fotorreceptoras, que actúan aguas abajo de la proteína Dock. Este estudio revela Pak Pak.
Área de la Ciencia:
- La neurociencia es la neurociencia.
- Biología celular Biología celular.
- Biología del desarrollo Biología del desarrollo.
Sus antecedentes:
- La proteína adaptadora SH2/SH3 Dock está implicada en la transducción de señales desde los receptores de guía hasta el citoesqueleto de actina en los conos de crecimiento de los fotorreceptores (células R) de Drosophila.
- Comprender los mecanismos moleculares de la orientación de los axones es crucial para el desarrollo y la reparación neuronal.
Objetivo del estudio:
- Investigar el papel de la quinasa activada por Drosophila p21 (Pak) en la vía Dock que regula la orientación y la orientación de los axones de las células R.
- Para aclarar la relación funcional entre Dock y Pak in vivo.
Principales métodos:
- Estudios de co-localización de Dock y Pak en axones de células R y conos de crecimiento.
- Análisis de los fenotipos de pérdida de función para Dock y Pak.
- Evaluación de la actividad de la cinasa de Pak y los sitios de unión para Dock y Cdc42/Rac.
- Estudios de ganancia de función utilizando un Pak (Pak(myr) atado a la membrana.
- Experimentos de rescate de mutantes de muelle utilizando la expresión retiniana de Pak (((myr).
Principales resultados:
- Dock y Pak se colocalizan en los axones de las células R y los conos de crecimiento e interactúan físicamente.
- Las mutaciones de pérdida de función en Dock y Pak resultan en fenotipos indistinguibles.
- La conectividad normal de las células R requiere la actividad de la cinasa de Pak y su unión a Dock y Cdc42/Rac.ac.
- La expresión retiniana de Pak (((myr) rescata los defectos de conectividad de las células R en los mutantes dock.
Conclusiones:
- Drosophila Pak es un regulador crítico de la orientación y orientación de los axones de las células R.
- Pak funciona como un efector aguas abajo de Dock in vivo.
- La vía Dock-Pak es esencial para establecer una conectividad neuronal adecuada en el sistema visual.
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