Disease relevance of Poly aug

• Binding and cross-linking of the uncharged, modified tRNAs to E. coli ribosomes have been studied with and without poly(A,U,G) as a message, under conditions directing uncharged tRNAs preferentially to the P-site [1].
• In addition, initiation complex formation on uncapped cowpea mosaic virus RNA and on poly(A,U,G) was only slightly stimulated by ATP, much less than in the case of the capped RNAs [2].

High impact information on Poly aug

• Purified IF3(mt) promotes initiation complex formation on mitochondrial 55 S ribosomes in the presence of mitochondrial initiation factor 2 (IF2(mt)), [(35)S]fMet-tRNA, and either poly(A,U,G) or an in vitro transcript of the cytochrome oxidase subunit II gene as mRNA [3].
• In the presence of N-fMet-tRNAfMet and poly(A,U,G) or in the presence of N-acetyl-Phe-tRNAPhe and poly(U), initiation factor IF2 causes an additional decrease of the uncoupled EF-G GTPase activity [4].
• In addition, phosphorylation of 40 S ribosomal subunits by the cAMP-dependent protein kinase inhibited translation of poly(A,U,G) by 30% in a reconstituted protein-synthesizing system [5].
• Mammalian mitochondrial translational initiation factor 3 (IF3(mt)) promotes initiation complex formation on mitochondrial 55S ribosomes in the presence of IF2(mt), fMet-tRNA and poly(A,U,G) [6].

Anatomical context of Poly aug

• The IF-2mt-mediated binding of fMet-tRNAi(Met) to mitochondrial ribosomes is dependent on the presence of a message such as poly(A,U,G) and on GTP [7].

Analytical, diagnostic and therapeutic context of Poly aug

• The purification was monitored by Western immunoblotting and the activity of the purified factor was tested by measuring the stimulation of binding of the initiator fMet-tRNA(Met)f to 70S ribosomes in the presence of GTP and poly(A,U,G) as messenger RNA [8].

References