Pyne, N J and Freissmuth, M and Pyne, S (1992) Phosphorylation of the recombinant spliced variants of the alpha-sub-unit of the stimulatory guanine-nucleotide binding regulatory protein (Gs) by the catalytic sub-unit of protein kinase A. Biochemical and Biophysical Research Communications, 186 (2). pp. 1081-1086. ISSN 1090-2104Full text not available in this repository. (Request a copy from the Strathclyde author)
Both GS alpha-1 and GS alpha-4 were phosphorylated by the purified catalytic sub-unit of protein kinase A. Phosphate incorporation into 220 pmol and 190 pmol of GS alpha-4 and GS alpha-1 after a 1 hour incubation with kinase was 14 pmol and 10 pmol, respectively. These low levels of phosphorylation are due to the thermal lability of purified recombinant GS alpha. However, the phosphorylation was inhibited by guanine nucleotides (GDP-beta-S, GppNHp and GTP) and is, therefore, a specific event. We suggest that, as for GS alpha phosphorylation by protein kinase C (Pyne et al., 1992), the guanine nucleotide-free form of GS alpha is the most likely substrate. Guanine-nucleotides reduce the lifetime and, therefore availability for phosphorylation, of guanine-nucleotide free GS alpha. GS alpha phosphorylation by protein kinase A in vitro provides preliminary evidence that a similar phosphorylation of GS alpha may be an important regulatory event in cells.
|Keywords:||autoradiography, brain, electrophoresis, polyacrylamide gel, escherichia coli, GTP-binding proteins, genetic variation, guanosine diphosphate, guanosine triphosphate, guanylyl imidodiphosphate, kinetics, macromolecular substances, molecular weight, phosphorus radioisotopes, protein kinases, RNA precursors, RNA splicing, recombinant proteins , thionucleotides, Therapeutics. Pharmacology, Biochemistry, Cell Biology, Molecular Biology, Biophysics|
|Subjects:||Medicine > Therapeutics. Pharmacology|
|Department:||Faculty of Science > Strathclyde Institute of Pharmacy and Biomedical Sciences|
|Depositing user:||Pure Administrator|
|Date Deposited:||15 Nov 2011 05:18|
|Last modified:||04 May 2016 20:20|