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Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation
Published on: January 6, 2016
La inducción dependiente de Ras de las respuestas celulares por la fosfatidilinositol-3 quinasa constitutivamente
1Cardiovascular Research Institute, University of California, San Francisco 94143-0130, USA.
Science (New York, N.Y.)
|April 7, 1995
Resumen
La fosfatidilinositol 3-cinasa (PI3K) regula los diversos procesos celulares. que se encuentran en el cuerpo humano. La PI3K (p110) constitutivamente activa indujo la transcripción génica y la maduración de los ovocitos, lo que demuestra su papel en las vías de señalización dependientes de Ras.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- La fosfatidilinositol 3-cinasa (PI3K) es una enzima clave activada por los factores de crecimiento.
- Comprender las funciones reguladoras específicas de PI3K requiere estudiar su actividad independiente de la estimulación del factor de crecimiento.
Objetivo del estudio:
- Para investigar las respuestas celulares específicas reguladas por PI3K.
- Para caracterizar la función de un mutante PI3K constitutivamente activo (p110).
Principales métodos:
- Se construyó y expresó un mutante PI3K p110 constitutivamente activo.
- PI3K evaluado y la actividad de la proteína quinasa de p110.
- Estudió la transcripción génica (fos promotor) en las células 3T3 de los NIH.
- Investigó la señalización Ras y la maduración de los ovocitos en ovocitos de Xenopus laevis.
Principales resultados:
- El mutante p110 mostró una alta actividad de PI3K y proteína quinasa.
- Expresión de la transcripción del promotor fos inducida por p110 en las células 3T3 del NIH.
- La expresión Ras dominante-negativa bloqueó la transcripción fos inducida por p110.
- En los ovocitos de Xenopus, p110 aumentó Ras ligado al GTP, activó Raf-1 e indujo la maduración de los ovocitos.
- Estos efectos fueron Ras-dependientes.
Conclusiones:
- La activación de PI3K puede estimular de forma independiente diversos procesos celulares.
- La señalización de PI3K es crucial para eventos dependientes de Ras como la maduración de los ovocitos y la transcripción génica.
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