αCat forced dimerization promotes protrusion-dependent cell–cell contact. Split-screen video of mCherry-iDimerize- WT-ΔNαCat–expressing (left) and ΔNαCatKKR<3A mutant–expressing (right) cell couplets (red) coinfected with GFP-LifeAct (green). Labels and time stamps are incorporated within corresponding image frames. Note that addition of the B/B-dimerizer allows WT ΔNαCat-expressing couplets to close a gap between the two cells (yellow arrows) and remain in close proximity; this gap reappears upon addition of the wash-out (W/O) ligand. This activity is less prominent in an ΔNαCatKKR<3A mutant couplet.
