Stimulation of M-tRNAi binding to ribosomes by a/eIF2: 30 pmol of 70S ribosomes were incubated with SMet-tRNAi and increasing amounts of a/eIF2 (complete trimer, α–γ dimer or the γ-subunit only)

<p><b>Copyright information:</b></p><p>Taken from "The archaeal eIF2 homologue: functional properties of an ancient translation initiation factor"</p><p>Nucleic Acids Research 2005;33(6):1804-1812.</p><p>Published online 23 Mar 2005</p><p>PMCID:PMC1069517.</p><p>© The Author 2005. Published by Oxford University Press. All rights reserved</p> The samples were analysed on a non-denaturing polyacrylamide gel (left panel). Lane 1, [S]Met-tRNAi alone; lane 2, 70S ribosomes were incubated with [S]Met-tRNAi without a/eIF2; lanes 3–5, 70S ribosomes were incubated with [S]Met-tRNAi in the presence of 50 (lane 3), 100 (lane 4) and 150 (lane 5) pmol of the γ-subunit; lanes 6–8, 70S ribosomes were incubated with [S]Met-tRNAi in the presence of 50 (lane 6), 100 (lane 6) and 150 (lane 8) pmol of the α–γ dimer; and lanes 9–11, 70S ribosomes were incubated with [S]Met-tRNAi in the presence of 50 (lane 9), 100 (lane 10) and 150 (lane 11) pmol of the trimer. The position of the 30S ribosomal subunit (arrow) was determined separately by Coomassie blue staining. The amount of tRNA bound to ribosomes was quantified using an Instant Imager apparatus (right panel). The total amount of radioactivity in each lane is somewhat variable owing to deacylation undergone by free Met-tRNAi during the run. Circles, complete trimer; triangles: α–γ dimer; and squares, γ-subunit