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Assay for Adhesion and Agar Invasion in S. cerevisiae
Published on: November 8, 2006
Funciones inhibidoras y activadoras para MAPK Kss1 en la vía de señalización del crecimiento filamentoso de S.
J G Cook1, L Bardwell, J Thorner
1Department of Molecular and Cell Biology, University of California, Berkeley 94720-3202, USA.
Nature
|November 18, 1997
Resumen
Las cascadas de proteína quinasa activada por mitógeno (MAPK) regulan las respuestas celulares. En la levadura, Ste7 activa Kss1 para el crecimiento invasivo, revelando Kss1.
Área de la Ciencia:
- Las vías de señalización celular.
- Biología molecular La biología molecular.
- Genética de la levadura genética de la levadura.
Sus antecedentes:
- Las cascadas de proteína quinasa activada por mitógeno (MAPK) son cruciales para las respuestas celulares a estímulos externos y cambios ambientales.
- En Saccharomyces cerevisiae, la MAPK quinasa (MAPKK) Ste7 está involucrada en el apareamiento y las vías de crecimiento invasivo.
- Los roles específicos de los objetivos Kss1 y Fus3 de MAPK en el crecimiento invasivo no estaban claros anteriormente.
Objetivo del estudio:
- Aclarar el papel de Ste7 y sus objetivos MAPK en la vía de crecimiento invasivo de Saccharomyces cerevisiae.
- Para determinar si Ste7 actúa en objetivos no MAPK, como se hipotetizó anteriormente.
- Para caracterizar la función de Kss1 en el crecimiento invasivo.
Principales métodos:
- El análisis genético en Saccharomyces cerevisiae.
- Investigando las vías de señalización de MAPK.
- Comparación de cepas de levadura de tipo salvaje y MAPK-deficiente.
Principales resultados:
- Kss1 fue identificado como el objetivo primario de MAPK de Ste7 en la respuesta al crecimiento invasivo.
- Kss1 inactivo actúa como un regulador negativo del crecimiento invasivo.
- La activación de Ste7 cambia Kss1 de un inhibidor a un activador, aliviando la regulación negativa.
Conclusiones:
- El MAPK Kss1 juega un papel importante en el crecimiento invasivo, funcionando incluso en su estado no activado.
- La acción de Ste7 sobre Kss1 es fundamental para promover el crecimiento filamentoso.
- Tanto las vías dependientes como las independientes de MAPK contribuyen al hambre de nitrógeno y al crecimiento filamentoso estimulado por Ras.
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