Calmodulin-dependent multiprotein kinase and protein kinase C phosphorylate the same site on HMG-CoA reductase as the AMP-activated protein kinase.
Calmodulin-dependent multiprotein kinase and protein kinase C phosphorylate and inactivate both intact, microsomal HMG-CoA reductase, and the purified 53 kDa catalytic fragment. Isolation of the single phosphopeptide produced by combined cleavage with cyanogen bromide and Lys-C proteinase reveals that this is due to phosphorylation of a single serine residue near the C-terminus, corresponding to serine-872 in the human enzyme. This is identical with the single serine phosphorylated by the AMP-activated protein kinase. The nature of the protein kinase responsible for phosphorylation of this site in vivo is discussed.
Clarke
P R
PR
Department of Biochemistry, The University, Dundee, Scotland, UK.
Hardie
D G
DG
D000595:Amino Acid Sequence; D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D006863:Hydrogen-Ion Concentration; D006903:Hydroxymethylglutaryl CoA Reductases / Q000378:metabolism*; D008861:Microsomes / Q000201:enzymology; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis; D010766:Phosphorylation; D010768:Phosphoserine / Q000378:metabolism; D011493:Protein Kinase C / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism*; D051381:Rats
D010446:Peptide Fragments; D010768:Phosphoserine; D006903:Hydroxymethylglutaryl CoA Reductases; D011494:Protein Kinases; D011493:Protein Kinase C; D017871:Calcium-Calmodulin-Dependent Protein Kinases