Role of acidic phosphoproteins in the partial reconstitution of the active 60 S ribosomal subunit.
We have recently shown that rat liver 60 S ribosomal subunits active in protein synthesis can be reconstituted from inactive core particles lacking 30% of the total proteins, mainly L10a, L12, L22, L24, A33 and the acidic phosphoproteins P1-P2, obtained by treatment of 60 S subunits with dimethylmaleic anhydride [(1987) Eur. J. Biochem. 163, 15-20]. In this study, an ethanol extract of the 60 S subunit which contains only P1 P2 was also shown to be effective in reconstitution with the DMMA-core-particles: it strongly stimulated the EF-2-dependent GTP hydrolysis and, to a lesser extent, polyphenylalanine synthesis; like the DMMA wash it shifted the thermal denaturation curve of the DMMA-core particles towards that of control subunits. Prior dephosphorylation of the ethanol extract by alkaline phosphatase inhibited the reconstruction process.
D000818:Animals; D006160:Guanosine Triphosphate / Q000378:metabolism; D008099:Liver / Q000032:analysis; D008299:Maleic Anhydrides / Q000494:pharmacology; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors / Q000378:metabolism; D010750:Phosphoproteins / Q000502:physiology*; D010766:Phosphorylation; D014176:Protein Biosynthesis; D051381:Rats; D012269:Ribosomal Proteins / Q000502:physiology*; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism* / Q000648:ultrastructure
D008299:Maleic Anhydrides; D020652:Peptide Elongation Factor 2; D010445:Peptide Elongation Factors; D010750:Phosphoproteins; D012269:Ribosomal Proteins; C007474:2,3-dimethylmaleic anhydride; D006160:Guanosine Triphosphate