Activation by Cyclic GMP Binding Causes an Apparent Conformational Change in cGMP-dependent Protein Kinase
| Autor: | Jackie D. Corbin, Der-Ming Chu, Sharron H. Francis, Kennard A. Grimes |
|---|---|
| Rok vydání: | 1997 |
| Předmět: |
Conformational change
Protein Conformation Proteolysis Biochemistry Cyclic nucleotide binding Cyclic GMP-Dependent Protein Kinases medicine Animals Protein kinase A Cyclic GMP Molecular Biology chemistry.chemical_classification CGMP binding medicine.diagnostic_test Kinase Cell Biology Chromatography Ion Exchange Enzyme Activation Enzyme chemistry Chromatography Gel cardiovascular system Cattle Dimerization cGMP-dependent protein kinase |
| Zdroj: | Journal of Biological Chemistry. 272:31922-31928 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.272.50.31922 |
| Popis: | Cyclic nucleotide binding activates cyclic nucleotide-dependent protein kinases, but the molecular mechanism is unknown. In the present studies, cGMP binding to type Ialpha or type Ibeta cGMP-dependent protein kinase (PKG) caused (i) a large electronegative charge shift of each enzyme on ion exchange chromatography, (ii) an increase in the Stokes radius (3 A) of each enzyme, and (iii) a decreased mobility of type Ibeta PKG on native gel electrophoresis. These physical changes were not detected in the monomeric form of type Ibeta PKG upon activation by cGMP. However, the results of partial proteolysis of type Ialpha PKG revealed some degree of cGMP-induced conformational change within the PKG-monomer, since cGMP binding protects the PKG-monomer against chymotryptic cleavage. The altered sensitivity to proteolysis occurs at Met-200, which is located between the B and C alpha-helices in the high affinity site (site A), and implies that the cGMP-induced structural perturbations in this region may participate in activation of dimeric PKG. The cGMP-induced conformational effects observed using the physical separation methods are likely to reflect altered interactions within the dimeric PKG that are caused by structural alterations within the subunits. |
| Databáze: | OpenAIRE |
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