Brizuela, L., Draetta, G., Beach, D. (June 1989) Activation of human CDC2 protein as a histone H1 kinase is associated with complex formation with the p62 subunit. Proc Natl Acad Sci U S A, 86 (12). pp. 4362-6. ISSN 1091-6490
Preview |
PDF (Paper)
Beach PNAS 1989.pdf - Published Version Download (1MB) | Preview |
Abstract
p34 kinase, the product of the CDC2 gene, is a cell-cycle regulated protein kinase that is most active during mitosis. In HeLa cells, p34 kinase has previously been shown to exist in both a low- and a high-molecular-mass form, the latter of which is only found in cells in the G2/M phase of the cell cycle and contains a 62-kDa subunit. Here we show that although each form of the kinase phosphorylates casein in vitro, only the high-molecular-mass form uses histone H1 as substrate. The high-molecular-mass form of p34 kinase from nocodazole-treated HeLa cells was purified 6700-fold. The apparent molecular mass of the mitotic CDC2-encoded protein kinase complex was 220 kDa. The purified enzyme phosphorylated not only its endogenous 62-kDa subunit but also phosphorylated histone H1 with a Km of 3 microM and used ATP 40 times more efficiently than GTP (Km 54 microM and 2 mM, respectively). The enzyme activity was unaffected by cAMP, calcium/calmodulin, or by the heat-stable inhibitor of cAMP-dependent protein kinase. These characteristics are typical of growth-associated histone H1 kinase from different organisms. These results suggest that CDC2 protein may be activated as an M-phase-specific protein kinase in part by its association with the p62 subunit.
Item Type: | Paper |
---|---|
Uncontrolled Keywords: | CDC2 Protein Kinase Cell Cycle Chromatography, DEAE-Cellulose Chromatography, Gel Chromatography, Ion Exchange Enzyme Activation Hela Cells/cytology/enzymology Humans Kinetics Macromolecular Substances Molecular Weight Phosphoproteins/isolation & purification/*metabolism Protamine Kinase/*metabolism Protein Kinases/*metabolism Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, P.H.S. Substrate Specificity |
Subjects: | bioinformatics > genomics and proteomics > genetics & nucleic acid processing > protein structure, function, modification > protein types > enzymes > kinase > Protein kinase C |
CSHL Authors: | |
Communities: | CSHL labs > Beach lab |
Depositing User: | Gail Sherman |
Date: | June 1989 |
Date Deposited: | 28 Jul 2017 17:08 |
Last Modified: | 09 Nov 2017 20:46 |
PMCID: | PMC287269 |
Related URLs: | |
URI: | https://repository.cshl.edu/id/eprint/34834 |
Actions (login required)
Administrator's edit/view item |