Figure 6

Distinct spatial distribution of RALT and RALT ΔEBR in response to activation of ErbB receptors. Subconfluent cultures of serum-deprived NIH-EGFR/ErbB-2 (a–l) and NIH-EGFR (m–p) cells ectopically expressing either RALT or RALT ΔEBR were processed for immunocytochemistry before (a, e, i, c, g, k, m, o) or after stimulation with EGF (10 ng/ml) for 60 (b, f, j, d, h, l) or 15 min (n, p). NIH-EGFR/ErbB-2 cells (a–l) were double stained for ErbB-2 (a–d, green) and either RALT (e, f, red) or RALT ΔEBR (g, h, red). Upon EGF stimulation, RALT (f) relocates to vesicular perinuclear structures where it colocalizes with the EGFR/ErbB-2 chimera (b, merge in j), while RALT ΔEBR (h) does not show significant relocation and does not colocalizes with EGFR/ErbB-2 (d, merge in l). Also in EGF-treated NIH-EGFR cells (m–p), RALT (m, n) relocates from the cytosol to a vesicular compartment, whereas spatial distribution RALT ΔEBR (o, p) is not detectably altered by EGFR activation. Bars: 10 μm.