The Phosphorylation of Liver Ribosomal Proteins in Vivo

摘要: Abstract The phosphorylation of rat liver ribosomal proteins was increased by an order magnitude during regeneration. A large amount radioactivity associated with preparations ribosomes after administration [32P]orthophosphoric acid to partially hepatectomized rats; however, only a small fraction actually in phosphoproteins. Radioactivity removed from the pellet each following treatments: high concentrations potassium ions form subunits, cold trichloroacetic acid, hot tichloroacetic and organic solvents; remained treatment. 40 S subunit resistant treatment deoxyribonuclease ribonuclease but sensitive trypsin alkaline phosphatase; radioactive phosphate covalently bound serine. It shown two-dimensional polyacrylamide gel electrophoresis that all incorporated into single protein, S6. There were, addition, several (in some experiments as many five) derivatives S6 which contained increasing numbers phosphoserine residues. No protein phosphorylated.