Identification and characterization of cAMP-dependent protein kinase and its possible direct interactions with protein phosphatase-1 in marine dinoflagellates
| العنوان: | Identification and characterization of cAMP-dependent protein kinase and its possible direct interactions with protein phosphatase-1 in marine dinoflagellates |
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| المؤلفون: | John F. Dawson, Charles F.B. Holmes, Kathy He Wang |
| المصدر: | Biochemistry and Cell Biology. 74:559-567 |
| بيانات النشر: | Canadian Science Publishing, 1996. |
| سنة النشر: | 1996 |
| مصطلحات موضوعية: | Phosphopeptides, Molecular Sequence Data, Biochemistry, Protein Phosphatase 1, Cyclic AMP, Phosphoprotein Phosphatases, Animals, Protein phosphorylation, Amino Acid Sequence, Enzyme Inhibitors, Phosphorylation, Protein kinase A, Molecular Biology, biology, Calcineurin, Dinoflagellate, Protein phosphatase 1, Cell Biology, biology.organism_classification, Cyclic AMP-Dependent Protein Kinases, Peptide Fragments, Chromatography, Gel, Dinoflagellida, Calmodulin-Binding Proteins, Identification (biology), Signal transduction, Oligopeptides |
| الوصف: | We have examined the nature of signal transduction involving reversible protein phosphorylation in marine Prorocentrale species. Of particular interest is the marine dinoflagellate Prorocentrum lima in which the tumour promoter okadaic acid is produced and may interfere with signal transduction. We have identified cAMP-dependent protein kinase (PKA) activity in P. lima, P. micans, and P. minimum. The P. lima enzyme was characterized biochemically and appears to consist of two different isoforms in the R2C2configuration. Whole cell extracts of P. micans and P. minimum treated with the specific PKA inhibitor peptide PKI (5–24) or cAMP demonstrated altered intensities of phosphopeptide32P labeling, most likely involving regulation of a protein phosphatase via PKA activity. A primary candidate for PKA regulation is protein phosphatase-1 (PP-1), which in P. lima possesses a classical PKA consensus phosphorylation site. We demonstrate that a peptide fragment of PP-1 from P. lima corresponding to this PKA phosphorylation site can be effectively phosphorylated by PKA and dephosphorylated by calcineurin. We speculate that PP-1 activity among several lower eukaryotes may be mediated directly by reversible phosphorylation. Higher eukaryotes may have developed inhibitor proteins to provide more complex regulation of protein phosphatase activity.Key words: cAMP-dependent protein kinase, protein phosphatase-1, dinoflagellates, Prorocentrum lima, okadaic acid. |
| تدمد: | 1208-6002 0829-8211 |
| URL الوصول: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::96f5c78430058fce8c71903f6345a5fb https://doi.org/10.1139/o96-460 |
| حقوق: | CLOSED |
| رقم الأكسشن: | edsair.doi.dedup.....96f5c78430058fce8c71903f6345a5fb |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 12086002 08298211 |
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