Abstract
The C-subunit of type II cyclic AMP-dependent protein kinase from bovine heart was labelled with the fluorophore fluorescamine (FAM). The association of the dye-labelled subunit (CFAM) with the R-subunit isolated from the same source was monitored by fluorescence polarization spectroscopy. The stoichiometry of C to R in the final complex was close to 1:1. The affinity of the two subunits could be described by a dissociation constant in the nanomolar range. Holoenzyme (formed from CFAM and R) was titrated with cyclic AMP, and the changes in fluorescence anisotropy, due to dissociation of the holoenzyme, recorded. The titration curves were analysed in terms of a model which required computer simulation. Cyclic AMP-induced dissociation proceeds via one or more ternary complexes, and all four cyclic AMP-binding sites on the R-dimer are accessible in the holoenzyme. The dissociation constants describing the release of the C-subunits from the two ternary complexes containing four cyclic AMP molecules were both approx. 9 microM. The binding of two cyclic AMP molecules to protein kinase is necessary and sufficient to cause the dissociation of both C-subunits. The state of association at 'in vivo' concentrations of protein and cyclic AMP is discussed.
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Selected References
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- Brostrom M. A., Reimann E. M., Walsh D. A., Krebs E. G. A cyclic 3',5'-amp-stimulated protein kinase from cardiac muscle. Adv Enzyme Regul. 1970;8:191–203. doi: 10.1016/0065-2571(70)90017-8. [DOI] [PubMed] [Google Scholar]
- Builder S. E., Beavo J. A., Krebs E. G. The mechanism of activation of bovine skeletal muscle protein kinase by adenosine 3':5'-monophosphate. J Biol Chem. 1980 Apr 25;255(8):3514–3519. [PubMed] [Google Scholar]
- Chau V., Huang L. C., Romero G., Biltonen R. L., Huang C. Kinetic studies on the dissociation of adenosine cyclic 3',5'-monophosphate from the regulatory subunit of protein kinase from rabbit skeletal muscle. Biochemistry. 1980 Mar 4;19(5):924–928. doi: 10.1021/bi00546a016. [DOI] [PubMed] [Google Scholar]
- Corbin J. D., Keely S. L., Soderling T. R., Park C. R. Hormonal regulation of adenosine 3',5'-monophosphate-dependent protein kinase. Adv Cyclic Nucleotide Res. 1975;5:265–279. [PubMed] [Google Scholar]
- Corbin J. D., Reimann E. M. Assay of cyclic AMP-dependent protein kinases. Methods Enzymol. 1974;38:287–290. doi: 10.1016/0076-6879(74)38044-5. [DOI] [PubMed] [Google Scholar]
- Corbin J. D., Sugden P. H., Lincoln T. M., Keely S. L. Compartmentalization of adenosine 3':5'-monophosphate and adenosine 3':5'-monophosphate-dependent protein kinase in heart tissue. J Biol Chem. 1977 Jun 10;252(11):3854–3861. [PubMed] [Google Scholar]
- Corbin J. D., Sugden P. H., West L., Flockhart D. A., Lincoln T. M., McCarthy D. Studies on the properties and mode of action of the purified regulatory subunit of bovine heart adenosine 3':5'-monophosphate-dependent protein kinase. J Biol Chem. 1978 Jun 10;253(11):3997–4003. [PubMed] [Google Scholar]
- Erlichman J., Rosenfeld R., Rosen O. M. Phosphorylation of a cyclic adenosine 3':5'-monophosphate-dependent protein kinase from bovine cardiac muscle. J Biol Chem. 1974 Aug 10;249(15):5000–5003. [PubMed] [Google Scholar]
- Erlichman J., Rubin C. S., Rosen O. M. Physical properties of a purified cyclic adenosine 3':5'-monophosphate-dependent protein kinase from bovine heart muscle. J Biol Chem. 1973 Nov 10;248(21):7607–7609. [PubMed] [Google Scholar]
- Freyssinet J. M., Lewis B. A., Holbrook J. J., Shore J. D. Protein-protein interactions in blood clotting. The use of polarization of fluorescence to measure the dissociation of plasma factor XIIIa. Biochem J. 1978 Feb 1;169(2):403–410. doi: 10.1042/bj1690403. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hofmann F. Apparent constants for the interaction of regulatory and catalytic subunit of cAMP-dependent protein kinase I and II. J Biol Chem. 1980 Feb 25;255(4):1559–1564. [PubMed] [Google Scholar]
- Hofmann F., Beavo J. A., Bechtel P. J., Krebs E. G. Comparison of adenosine 3':5'-monophosphate-dependent protein kinases from rabbit skeletal and bovine heart muscle. J Biol Chem. 1975 Oct 10;250(19):7795–7801. [PubMed] [Google Scholar]
- Hofmann F., Bechtel P. J., Krebs E. G. Concentrations of cyclic AMP-dependent protein kinase subunits in various tissues. J Biol Chem. 1977 Feb 25;252(4):1441–1447. [PubMed] [Google Scholar]
- Peters K. A., Demaille J. G., Fischer E. H. Adenosine 3':5'-monophosphate dependent protein kinase from bovine heart. Characterization of the catalytic subunit. Biochemistry. 1977 Dec 27;16(26):5691–5697. doi: 10.1021/bi00645a007. [DOI] [PubMed] [Google Scholar]
- Rubin C. S., Erlichman J., Rosen O. M. Molecular forms and subunit composition of a cyclic adenosine 3',5'-monophosphate-dependent protein kinase purified from bovine heart muscle. J Biol Chem. 1972 Jan 10;247(1):36–44. [PubMed] [Google Scholar]
- Takio K., Smith S. B., Krebs E. G., Walsh K. A., Titani K. Primary structure of the regulatory subunit of type II cAMP-dependent protein kinase from bovine cardiac muscle. Proc Natl Acad Sci U S A. 1982 Apr;79(8):2544–2548. doi: 10.1073/pnas.79.8.2544. [DOI] [PMC free article] [PubMed] [Google Scholar]
- WEBER G. Polarization of the fluorescence of macromolecules. I. Theory and experimental method. Biochem J. 1952 May;51(2):145–155. doi: 10.1042/bj0510145. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Walsh D. A., Perkins J. P., Krebs E. G. An adenosine 3',5'-monophosphate-dependant protein kinase from rabbit skeletal muscle. J Biol Chem. 1968 Jul 10;243(13):3763–3765. [PubMed] [Google Scholar]
