Putative nuclear cdk2 substrates in normal and transformed cells.
The presence of putative substrates of cdk2 in a nuclear fraction obtained by DNase plus RNase extraction (S1 fraction) has been analyzed by immunoprecipitation using specific anti-cdk2 antibodies, followed by phosphorylation assays. S1 nuclear fractions from four different cellular types, two normal (rat hepatocytes and human T lymphocytes) and two transformed (HeLa and Namalwa cells), have been studied. Results indicate that the normal cells share three putative nuclear cdk2 substrates of 21, 37 and 57 kDa. On the other hand, only a substrate of 20 kDa is shared by the two transformed cell lines. On comparing the proliferating normal lymphocytes with the lymphoblastoid cell line Namalwa, it can be observed that they share two proteins of 40 and 70 kDa.
Jaumot
M
M
Department of Cell Biology, Faculty of Medicine, University of Barcelona, Spain.
Agell
N
N
Bachs
O
O
D000818:Animals; D042846:CDC2-CDC28 Kinases; D002455:Cell Division; D002461:Cell Line, Transformed; D002467:Cell Nucleus / Q000378:metabolism*; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D006918:Hydroxyurea / Q000494:pharmacology; D008099:Liver / Q000166:cytology / Q000378:metabolism*; D009687:Nuclear Proteins / Q000302:isolation & purification / Q000378:metabolism*; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051381:Rats; D013601:T-Lymphocytes / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D009687:Nuclear Proteins; D017346:Protein Serine-Threonine Kinases; D042846:CDC2-CDC28 Kinases; C495894:CDK2 protein, human; C495892:Cdk2 protein, rat; D051357:Cyclin-Dependent Kinase 2; D018844:Cyclin-Dependent Kinases; D006918:Hydroxyurea