Clarke P R, Hardie D G
Department of Biochemistry, The University, Dundee, Scotland, UK.
FEBS Lett. 1990 Aug 20;269(1):213-7. doi: 10.1016/0014-5793(90)81157-j.
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.
