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Assay for Adhesion and Agar Invasion in S. cerevisiae
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La cascada de quinasa HOG1 MAP de la levadura está regulada por un mecanismo de fosforelado de varios pasos en el
F Posas1, S M Wurgler-Murphy, T Maeda
1Dana-Farber Cancer Institute and Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, USA.
Cell
|September 20, 1996
Resumen
La levadura de brote utiliza un sistema de fosforelados de varios pasos que incluye Sln1p, Ypd1p y Ssk1p para la osmosensibilidad. Este mecanismo, iniciado por la autofosforilación de Sln1p, se propone como una vía universal de transducción de señales en procariotas y eucariotas.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología molecular La biología molecular.
- La bioquímica es la bioquímica.
Sus antecedentes:
- La osmosensibilidad es crucial para la adaptación celular a los cambios ambientales.
- La levadura de brote (Saccharomyces cerevisiae) emplea una compleja red de señalización para la osmorregulación.
- Los componentes clave incluyen un sistema de dos componentes (Sln1p, Ypd1p, Ssk1p) y una cascada de MAP quinasa (Ssk2p / Ssk22p, Pbs2p, Hog1p).
Objetivo del estudio:
- Para dilucidar el mecanismo de osmosis en Saccharomyces cerevisiae.
- Para detallar el relevo de fósforo de varios pasos dentro del transductor de señal de dos componentes.
- Proponer la universalidad de este mecanismo de fosforelaje.
Principales métodos:
- Análisis de las interacciones de proteínas y funciones de dominio (Sln1p, Ypd1p, Ssk1p).
- Investigación de la iniciación de la vía del fosfororreceptor y las etapas de transferencia de fosfato.
- Análisis comparativo de los mecanismos de transducción de señales en diferentes organismos.
Principales resultados:
- Sln1p, una proteína transmembrana, inicia el repuesto de fósforo a través de la autofosforilación en His576.
- El fosfato se transfiere secuencialmente a través de Sln1p-Asp-1144, Ypd1p-His64, y finalmente a Ssk1p-Asp554.
- El fosforelador descrito es un componente central de la osmosensibilidad de la levadura.
Conclusiones:
- El phosphorelay de varios pasos es un mecanismo crítico de osmosensing en la levadura en ciernes.
- Este mecanismo implica una transferencia secuencial precisa de fosfato entre residuos específicos de aminoácidos.
- El estudio propone que este repuesto de fósforo representa un aparato de transducción de señales conservado y universal.
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