Role of acidic phosphoproteins in the partial reconstitution of the active 60 S ribosomal subunit

• Published in: FEBS letters 1987-05, Vol.216 (1), p.83-88
• Main Authors: Lavergne, Jean-Pierre, Conquet, François, Reboud, Jean-Paul, Reboud, Anne-Marie
• Format: Article
• Language: English
• Subjects: 60 S subunit; Animals; Biochemistry, Molecular Biology; Biological and medical sciences; Cell structures and functions; Fundamental and applied biological sciences. Psychology; Guanosine Triphosphate - metabolism; Life Sciences; Liver - analysis; Maleic Anhydrides - pharmacology; Molecular and cellular biology; Peptide Elongation Factor 2; Peptide Elongation Factors - metabolism; Phosphoprotein; Phosphoproteins - physiology; Phosphorylation; Protein Biosynthesis; Rats; Reconstitution; Ribosomal Proteins - physiology; Ribosome; Ribosomes - drug effects; Ribosomes - metabolism; Ribosomes - ultrastructure
• ISSN: 0014-5793; 1873-3468
• DOI: 10.1016/0014-5793(87)80761-5

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-particies: 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.