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Identificación de los sitios de fosforilación regulados por el ciclo celular en la lámina nuclear C
1Department of Biochemistry and Biophysics, University of California, San Francisco 94143.
Cell
|May 18, 1990
Resumen
El factor promotor de la maduración (MPF) desencadena la ruptura de la envoltura nuclear durante la mitosis mediante la fosforilación de las láminas nucleares. Esta fosforilación conduce al desmontaje del filamento laminado, con la S6 quinasa II identificada como una enzima clave en este proceso.
Área de la Ciencia:
- Biología celular Biología celular.
- Biología Molecular Biología Molecular
- La bioquímica es la bioquímica.
Sus antecedentes:
- La mitosis implica la descomposición de la envoltura nuclear, un proceso regulado por el Factor de Promoción de la Maduración (MPF).
- Las láminas nucleares forman una red estructural que sostiene la envoltura nuclear y son objetivos conocidos durante la división celular.
Objetivo del estudio:
- Investigar el mecanismo por el cual el MPF induce el desmontaje de la lámina nuclear y la ruptura de la envolvente nuclear.
- Para identificar sitios específicos de fosforilación en las láminas nucleares y las quinasas involucradas.
Principales métodos:
- Utilizamos extracto de huevo de rana para estudiar la transición de interfase a mitosis inducida por la adición de MPF.
- Empleado laminado nuclear humano bacterialmente expresado C, ensamblado en filamentos in vitro.
- Se analizaron los sitios de fosforilación en las láminas utilizando técnicas de secuenciación en presencia y ausencia de MPF.
Principales resultados:
- El MPF indujo un aumento de la fosforilación de los filamentos C de la lámina nuclear en sitios específicos dentro del extracto de huevo de rana.
- El desmontaje del filamento laminado se observó simultáneamente con un aumento de la fosforilación.
- Se identificaron secuencias específicas de aminoácidos de sitios fosforilados, lo que sugiere múltiples actividades de la quinasa.
- La S6 quinasa II fue identificada como una potencial quinasa clave responsable de la fosforilación laminar.
Conclusiones:
- La fosforilación mediada por MPF es un paso crítico en el desmontaje de la lámina nuclear y la ruptura de la envoltura nuclear durante la mitosis.
- Los hallazgos resaltan el papel de las quinasas específicas, incluida la S6 quinasa II, en la regulación de la dinámica de la estructura nuclear durante la división celular.
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