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Diferentes requisitos para las proteínas NSF, SNAP y Rab en el transporte apical y basolateral en las células MDCK
E Ikonen1, M Tagaya, O Ullrich
1Cell Biology Programme, European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Cell
|May 19, 1995
Resumen
El estudio revela una maquinaria molecular distinta para las vías de transporte de las células epiteliales. El transporte basolateral utiliza el mecanismo Rab-NSF-SNAP-SNARE, mientras que el transporte apical emplea diferentes componentes.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- El tráfico de membranas.
Sus antecedentes:
- Las células epiteliales polarizadas exhiben distintos dominios de la membrana apical y basolateral.
- La comprensión de los mecanismos moleculares que rigen el transporte de la membrana polarizada es crucial para la función celular.
Objetivo del estudio:
- Investigar las funciones de las proteínas NSF, SNAP, SNAREs y Rab en el transporte de la membrana polarizada en las células epiteliales.
- Para diferenciar la maquinaria molecular involucrada en las vías de transporte apical versus basolateral.
Principales métodos:
- Utilizó un sistema in vitro con células del riñón canino Madin-Darby (MDCK) permeabilizadas con estreptolisina O. Utilizó un sistema in vitro con células del riñón canino Madin-Darby (MDCK) permeabilizadas con estreptolisina O.
- Se evaluó el impacto de los anticuerpos contra NSF, alfa-SNAP, Rab-GDI y neurotoxinas en el transporte de TGN a la membrana plasmática.
Principales resultados:
- El transporte basolateral de la red trans-Golgi (TGN) fue inhibido por anticuerpos anti-NSF y estimulado por alpha-SNAP.
- El transporte apical desde el TGN no se vio afectado por los anticuerpos anti-NSF ni por el alfa-SNAP.
- El transporte apical fue insensible a las neurotoxinas Rab-GDI y tetanus/botulinum, que inhibieron el transporte basolateral.
Conclusiones:
- El mecanismo Rab-NSF-SNAP-SNARE está específicamente involucrado en el transporte basolateral de la membrana.
- Una maquinaria molecular distinta media la entrega vesicular a la superficie celular apical.
- Este estudio aclara los requisitos moleculares específicos de la vía para el tráfico de membranas polarizadas.
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