Membrane-anchored cyclin A2 triggers Cdc2 activation in Xenopus oocyte.
In Xenopus oocyte, the formation of complexes between neosynthesized cyclins and Cdc2 contributes to Cdc2 kinase activation that triggers meiotic divisions. It has been proposed that cytoplasmic membranes could be involved in this process. To investigate this possibility, we have injected in the oocyte two undegradable human cyclin A2 mutants anchored to the endoplasmic reticulum (ER) membrane. They encode fusion proteins between the truncated cyclin A2-Delta152 and a viral or cellular ER-targeting domain. We show that both mutants are fully functional as mitotic cyclins when expressed in Xenopus oocytes, bind Cdc2 and activate M-phase promoting factor.
Faivre
J
J
INSERM U370, Institut Pasteur/Necker, Faculté de Médecine Necker, Paris, France.
Frank-Vaillant
M
M
Poulhe
R
R
Mouly
H
H
Bréchot
C
C
Sobczak-Thépot
J
J
Jessus
C
C
D000818:Animals; D042846:CDC2-CDC28 Kinases; D002462:Cell Membrane / Q000378:metabolism; D019925:Cyclin A / Q000378:metabolism*; D056751:Cyclin A2; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D004789:Enzyme Activation; D009865:Oocytes / Q000201:enzymology*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D029867:Xenopus Proteins; D014982:Xenopus laevis
C503725:CCNA2 protein, Xenopus; C503721:CCNA2 protein, human; D019925:Cyclin A; D056751:Cyclin A2; D029867:Xenopus Proteins; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495891:Cdk2 protein, Xenopus; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases