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La mutación de los genes de control del ciclo celular de la levadura de fisión elimina la dependencia de la mitosis
Cell
|February 23, 1990
Resumen
La entrada de la mitosis en la levadura de fisión se basa en la síntesis del ADN, pero este enlace se rompe en ciertos mutantes "wee". Esto sugiere que la activación de cdc25 + requiere eventos previos del ciclo celular como la replicación del ADN.
Área de la Ciencia:
- Regulación del ciclo celular Regulación del ciclo celular
- Biología molecular La biología molecular.
- Genética de la levadura genética de la levadura.
Sus antecedentes:
- La entrada de la mitosis en la levadura de fisión está regulada por la quinasa p34cdc2, modulada por cdc25+ (activador) y wee1+ (inhibidor).
- Los mutantes "wee" exhiben un tiempo de mitosis alterado debido a los controles regulatorios eludidos.
Objetivo del estudio:
- Para investigar el papel de la dependencia de la síntesis del ADN en la entrada de la mitosis en la levadura de fisión.
- Para determinar cómo eludir los controles cdc25+ o wee1+ afecta a esta dependencia.
Principales métodos:
- Análisis de mutantes "wee" con actividad cdc2+ o cdc25+ alterada.
- Observación de la progresión de la mitosis en relación con la síntesis del ADN.
Principales resultados:
- La pérdida de la dependencia de la mitosis en la síntesis del ADN se observó en los mutantes "wee" donde el control de cdc25+ se evitó (a través de mutaciones cdc2+ o sobreproducción de cdc25+).
- La dependencia de la síntesis del ADN se mantuvo cuando se omitió el control wee1+.
Conclusiones:
- La activación de cdc25+ parece requerir la finalización de eventos anteriores del ciclo celular, incluida la síntesis de ADN.
- Este mecanismo vincula la activación de la quinasa p34cdc2 con la finalización de eventos anteriores, lo que potencialmente explica por qué algunos embriones tempranos carecen de la dependencia de la replicación del ADN para la mitosis.
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