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La proteína tirosina quinasa Wee1B es esencial para la salida de la metafase II en los ovocitos de ratón
Jeong Su Oh1, Andrej Susor, Marco Conti
1Center for Reproductive Sciences, Department of Obstetrics, Gynecology and Reproductive Sciences, University of California, San Francisco, CA 94143-0556, USA.
Science (New York, N.Y.)
|April 2, 2011
Resumen
La actividad de la quinasa Wee1B es crucial para la activación del óvulo, controlando la inactivación de Cdc2 y la formación de pronúcleos. Su regulación a la baja impide la progresión adecuada del ciclo celular después de la fertilización.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología del desarrollo Biología del desarrollo.
- Biología Molecular Biología Molecular
Sus antecedentes:
- La síntesis y degradación de la ciclina regulan la actividad de la cinasa Cdc2 a lo largo del ciclo celular.
- La inactivación de Cdc2 por la fosforilación de Wee1B causa la detención de la G2-profasa en los ovocitos.
- El papel de Wee1B en la transición de metafase a anafase sigue sin estar claro.
Objetivo del estudio:
- Investigar el papel de Wee1B en la regulación de la actividad de Cdc2 durante la activación del óvulo.
- Para determinar si se requiere la fosforilación mediada por Wee1B para la transición de metafase a anafase.
Principales métodos:
- Investigó la reactivación de la vía Wee1B durante la activación del huevo.
- Se examinó el efecto de la regulación descendente de Wee1B en la formación del pronúcleo.
- Se evaluó el impacto de la quinasa II dependiente de calcio-calmodulina (CaMKII) en la actividad de Wee1B y la salida de la metafase II.
Principales resultados:
- La reactivación de la vía Wee1B desencadena una disminución de la actividad de Cdc2 durante la activación del huevo.
- La regulación a la baja de Wee1B perjudica la formación de pronúcleos en respuesta a las señales de calcio.
- CaMKII activa Wee1B, y esta activación es necesaria para la salida impulsada por CaMKII de la metafase II.
Conclusiones:
- La salida de la metafase II requiere tanto la degradación de la ciclina B como la fosforilación inhibidora de Cdc2 por Wee1B.
- La fosforilación de Cdc2 mediada por Wee1B es esencial para la progresión adecuada del ciclo celular durante la activación del óvulo.
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