spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

Right arrow Help viewing high resolution images
Right arrow Return to article
(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.


Figure 1


Fig. 1. Characterization of sea urchin eIF4G. (A) Schematic diagram of SgIF4G protein deduced from the cDNA. The SgIF4G conserved domains MIF4G (middle domain of eIF4G: predicted eIF4A- and eIF3-binding domain), MA3 (domain present in DAP-5, eIF4G and MA-3), eIF5C (domain at the C-termini of GCD6, eIF-2B {epsilon}, eIF5 and eIF4G) and amino acid sequence corresponding to the eIF4E- and PABP-binding sites are indicated. The last 1005 residues of the predicted protein scored 40% with human eIF4GI. The sequence corresponding to the peptide used to generate an SgIF4G-GST fusion protein is indicated by a grey line. Numbers indicate the positions of amino acids in the protein sequence deduced from the cDNA sequence. (B) Protein alignment of the eIF4E-binding domain of sea urchin eIF4G, and human eIF4GI and eIF4GII. Identical and conserved amino acid residues are on black and grey background, respectively. The common eIF4E recognition motif is indicated above (where x is any amino acid and {Phi} is an aliphatic residue, usually L, M or F). (C) Protein alignment of the PABP-binding region of SgIF4G and human eIF4GI and eIF4GII. Residues suggested to be important for the interaction with PABP in human eIF4GI are indicated above (Imataka and Sonenberg, 1997; Wakiyama et al., 2000). (D) A single ortholog of SgIF4G is expressed in unfertilized eggs of sea urchin. Northern blot derived from gel loaded with 1 or 8 µg poly(A+) mRNAs from unfertilized sea urchin eggs was assessed for the presence of SgIF4G transcript as described in Materials and Methods. (E) The SgIF4G fusion protein (GST-SgIF4G) interacts with a mouse eIF4E-fusion protein (GST-mIF4E). After incubation, the fusion proteins were affinity-purified using an m7GTP column (lanes 1-5), analysed by immunoblotting and detected by chemifluorescence using an anti-GST antibody as described in Materials and Methods. Affinity-purified proteins were compared with the GST-fusion proteins loaded separately (lanes 6-8). The positions of the respective GST proteins are indicated with arrows on the right side of the panel.





Right arrow Return to article