Phosphorylation of ribosomal proteins by cyclic AMP independent protein kinase (ribosomal casein kinase) from soybean cotyledons (Glycine max L.).
Ribosomal subunits prepared by zonal centrifugation of 80 S ribosomes from 1-day-old soybean cotyledons were active in in vitro polyphenylalanine synthesis. 40 S and 60 S subunits contained 32 and 43 ribosomal proteins respectively, when analyzed by two-dimensional polyacrylamide gel electrophoresis. A cyclic AMP (cAMP) independent protein kinase associated with ribosomes was isolated from the ribosomal salt wash fraction and was found to be similar in chromatographic properties and substrate requirements to cAMP independent casein kinase II present in post-ribosomal supernatant. Soybean cotyledon ribosomal casein kinase in vitro phosphorylates 4 polypeptides of 40 S ribosomal subunit.
Department of Biology, University of Windsor, Windsor, Ontario, Canada.
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S
Gowda
Department of Biology, University of Windsor, Windsor, Ontario, Canada.
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DT
Pillay
Glycine max L.; Phosphorylation of ribosomal proteins; Ribosomal casein kinase; Ribosomal proteins; Soybean cotyledons; cAMP Independent casein kinase