Fig. 6. Rho GTPases and cytoskeleton participate in Vav and SLP76 phosphorylation. Jurkat cells, treated with 0.1 µg/ml of Toxin B for two hours or with cytochalasin for 30 minutes or left untreated were cultured for 15 minutes at 37°C on plates coated with anti-CD82 (C11, 50 µg/ml) or left uncoated. After lysis (5x10⁶ cells) in SDS sample buffer, SDS-PAGE analysis was performed. Upper panel, immunoblot with anti-phosphotyrosine antibodies (4G10). Stimulation: lanes 1, no mAb; lane 2-4, anti-CD82. Cell treatment: lanes 1-2, untreated cells; lanes 3, Toxin B; lane 4, cytochalasin. Lower panel: after dehybridization, the same membrane was re-probed with anti-ZAP70 rabbit antisera.