Journal: Nucleic Acids Research
Article Title: RNA-tethering assay and eIF4G:eIF4A obligate dimer design uncovers multiple eIF4F functional complexes
doi: 10.1093/nar/gkaa646
Figure Lengend Snippet: ( A ) Schematic representation of eIF4G homologs highlighting functional domains. The numbering is based on Gene Accession NM_182917.4 (eIF4GI), NM_001198802.2 (eIF4GII) and NM_001418.4 (eIF4GIII). Domain organization is based on Marintchev et al. . ( B ) Schematic diagram illustrating internal recruitment of 40S ribosomes and associated initiation factors (represented by a yellow star) via a λN-4G fusion, based on the tethering assay . ( C ) Schematic representation of retroviral-based expression system for ectopic production of eIF4GI in cells. Shown is the vector designed to express the middle domain of eIF4GI (amino acids 653–1131) fused to two λN domains. ( D ) Western blot denoting expression of λ–4GIm in translation extracts prepared from MSCV/λ–4GIm—infected K-2 cells (K-2/λ–4GIm). ( E ). Top: Schematic representation of bicistronic reporters used in this study. Shown are variations in the inter-cistronic region (ICR) tested. BBoxes or scrambled sequence controls (Scr) are present one (1×), three (3×) or six (6×) times, with a spacing of 26 or 52 nucleotides. Bottom: Luciferase production following in vitro translation of 10 μg/ml of the indicated mRNA reporters in either K-2 or K-2/λ-4GIm extracts. Values are normalized to the Scr control mRNAs of the same length and copy number (see ) and represent the average of 5 biological replicates, with each experiment performed in technical duplicates. ± SD. ns, not significant, ** P = 0.02. ( F ). Top: Schematic representation of monocistronic reporters used in this study. Bottom: Luciferase production following in vitro translation of 4 μg/ml of the indicated mRNA reporters in the indicated extracts. Values are normalized to the Scr control mRNAs of the same length. n = 5 biological replicates, ± SD.
Article Snippet: Cells were lysed 12–16 h later using Passive Lysis Buffer (Promega) and FF and Ren luciferase activity determined on a Fluostar 96-well plate reader BMG Labtech ( ).
Techniques: Functional Assay, Retroviral, Expressing, Plasmid Preparation, Western Blot, Infection, Sequencing, Luciferase, In Vitro, Control