Fig. 4

The Cisd2 KKEV motif of Cisd2 interacts with the COPI complex. a Synthetic peptides corresponding to the cytosolic C-terminal sequence of Cisd1, Cisd2 and the yeast WBP1 protein were synthesized and biotinylated. As a negative control, we used a peptide where the two lysine residues of WBP1 were replaced with two serine residues (WBP1-SS). b The indicated peptides were immobilized on beads and incubated with a lysate from COS7 cells. The proteins bound to the peptides were then separated on an acrylamide gel and detected by Coomassie staining. The position of the α (≈160 kDa) β, β’ and γ (≈110 kDa) subunits of the COPI complex are indicated with stars. c The gel shown in b was restained with silver to detect less abundant proteins. The COPI complex interacted specifically with the WBP1 cytosolic domain, as well as with the Cisd2 cytosolic domain