The phosphorylation of 40-S ribosomal subunits by cyclic-nucleotide-dependent and protease-activated protein kinases from rabbit reticulocytes was studied in vitro. Under optimal conditions the CAMP-dependent protein kinases incorporated up to 2 mol phosphate/mol S6. The electrophoretic mobility of S6 following phosphorylation indicated that this value was not an average for a population of maximally phosphorylated and non-phosphorylated S6 but represented a uniform population of diphosphorylated 40-S ribosomal subunits. Tryptic digests of S6 were analyzed by two-dimensional fingerprinting following phosphorylation with the CAMP-dependent protein kinase; two phosphopeptides, A and B, were observed. When 40-S ribosomal subunits were examined with the cGMP-dependent protein kinase, 1 mol phosphate was incorporated/mol S6. Upon analysis of the phosphopeptides obtained with the cGMP-dependent protein kinase, only peptide A was observed. S6 was also modified by a cyclic-nucleotide-independent protein kinase, protease-activated kinase 11, following activation of the enzyme by limited proteolytic digestion. These findings suggest that a multiple protein kinase system may regulate the phosphorylation-state of S6. A second ribosomal protein, S10, was phosphorylated by a different cyclic-nucleotide-independent protein kinase, protease-activated kinase I, and up to 1 mol phosphate was incorporated.

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Background: Our objective was to determine the assessment of cardiovascular risk by family physicians. Methods: A questionnaire was sent by mail or fax regarding both awareness and use of the various CV risk scores in southeastern Ontario. Results: Of 181 family physicians surveyed, 96% were aware of at least one CV risk score and 40% were aware of the JUPITER study. Despite this awareness, 72% simply counted risk factors to assess risk, rather than to calculate risk using established scoring methods. Only 23% used the JUPITER study criteria. This suggests an underestimated of overall CV risk by family physician's practicing in southeastern Ontario. Interpetation: Cardiovascular risk in primary care is being underestimated in southeastern Ontario. Additional knowledge translation strategies are required to enhance the family physician's awareness and use of established risk scoring methods if we are to reduce the burden of CV disease.