TY - JOUR
T1 - cdc2 protein kinase is complexed with both cyclin A and B
T2 - Evidence for proteolytic inactivation of MPF
AU - Draetta, Giulio
AU - Luca, Frank
AU - Westendorf, Joanne
AU - Brizuela, Leonardo
AU - Ruderman, Joan
AU - Beach, David
N1 - Funding Information:
We thank Ellen LeMosy for providing cyclin A antiserum, and Dave Greene and Jim Duffy for help in preparation of the figures. Maureen McLeod, Bob Booher, Lisa Molz, Ellen LeMosy, and Bernard Ducom-mun are thanked for critical comments on the manuscript. This work was supported by National Institutes of Health grants GM39620 to D. B. and G. D. and HD23696 to J. V. R.
PY - 1989/3/10
Y1 - 1989/3/10
N2 - In the clam, Spisula, two previously described proteins known as cyclin A and B display the unusual property of selective proteolytic degradation at the end of each mitosis. We show here that clam oocytes and embryos contain a cdc2 protein kinase. This protein kinase is a component of the M phase promoting factor (MPF) in frog eggs and the M phase-specific histone H1 kinase in starfish. Clam cdc2 is found in association with both cyclin A and B, probably not as a trimolecular association, but as separate cdc2/cyclin A and cdc2/cyclin B complexes. Clam cdc2 and the associated cyclins bind to p13suc1-Sepharose. The p13-bound complex, and also anti-cyclin A or B immunoprecipitates, each display cell cycle-dependent histone H1 kinase activity. We suggest that in addition to the cdc2 protein kinase, the cyclins are further components of the M phase promoting factor and that cyclin proteolysis provides the mechanism of MPF inactivation and thus exit from mitosis.
AB - In the clam, Spisula, two previously described proteins known as cyclin A and B display the unusual property of selective proteolytic degradation at the end of each mitosis. We show here that clam oocytes and embryos contain a cdc2 protein kinase. This protein kinase is a component of the M phase promoting factor (MPF) in frog eggs and the M phase-specific histone H1 kinase in starfish. Clam cdc2 is found in association with both cyclin A and B, probably not as a trimolecular association, but as separate cdc2/cyclin A and cdc2/cyclin B complexes. Clam cdc2 and the associated cyclins bind to p13suc1-Sepharose. The p13-bound complex, and also anti-cyclin A or B immunoprecipitates, each display cell cycle-dependent histone H1 kinase activity. We suggest that in addition to the cdc2 protein kinase, the cyclins are further components of the M phase promoting factor and that cyclin proteolysis provides the mechanism of MPF inactivation and thus exit from mitosis.
UR - http://www.scopus.com/inward/record.url?scp=0024565997&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024565997&partnerID=8YFLogxK
U2 - 10.1016/0092-8674(89)90687-9
DO - 10.1016/0092-8674(89)90687-9
M3 - Article
C2 - 2538242
AN - SCOPUS:0024565997
SN - 0092-8674
VL - 56
SP - 829
EP - 838
JO - Cell
JF - Cell
IS - 5
ER -