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Updated: Jul 14, 2026

Studying Proteolysis of Cyclin B at the Single Cell Level in Whole Cell Populations

Studying Proteolysis of Cyclin B at the Single Cell Level in Whole Cell Populations

Published on: September 17, 2012

La inactivación del complejo p34cdc2-ciclina B por la tirosina quinasa WEE1 humana

L L Parker¹, H Piwnica-Worms

¹Department of Physiology, Tufts University School of Medicine, Boston, MA 02111.

Science (New York, N.Y.)

|September 25, 1992

Resumen

El producto del gen humano WEE1, una tirosina quinasa, inactiva el complejo p34cdc2-ciclina B, regulando la entrada en la mitosis. El Cdc25C humano invierte esta inhibición mediante la desfosforilación de p34cdc2.2.

Área de la Ciencia:

Biología celular Biología celular.
Biología Molecular Biología Molecular
La bioquímica es la bioquímica.

Sus antecedentes:

La entrada de la mitosis en Schizosaccharomyces pombe está regulada por el gen wee1+.
El producto del gen wee1+ fosforila p34cdc2 en la tirosina 15, inactivando el complejo p34cdc2-ciclina B.

Objetivo del estudio:

Para investigar la función del homólogo humano del gen wee1+ (WEE1Hu).
Para determinar si WEE1Hu regula directamente el complejo p34cdc2-ciclina B en las células humanas.

Principales métodos:

Sobreproducción de WEE1Hu en las bacterias.
Ensayos in vitro de la quinasa utilizando la quinasa WEE1 humana purificada y el complejo p34cdc2-ciclina B.
Análisis de la actividad de la proteína Cdc25C humana.

Principales resultados:

La quinasa WEE1 humana es específica de la tirosina.
WEE1Hu fosforila p34cdc2 en la tirosina 15, pero no en la treonina 14, inactivando el complejo p34cdc2-ciclina B.
Cdc25C humano desfosforila p34cdc2, revirtiendo la inhibición mediada por WEE1.

Conclusiones:

WEE1Hu regula directamente el complejo p34cdc2-ciclina B en las células humanas.
Una quinasa distinta de la WEE1Hu fosforila las p34cdc2 en la treonina 14.

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