DN3 require RasGRP1 for ERK phosphorylation in response to CXCR4 activation.

<p><b>A, B.</b> Bulk thymocytes were pre-treated with (right panels) or without (left panels) 20 µM of the PI3K inhibitor LY294002 and were stimulated with 10 nM SDF1α for 0, 1, 2, 3 or 5 minutes. <b>A.</b> Induction of p-ERK (pT202/pY204) was measured in DN3 (CD4⁻CD8⁻Thy1.2⁺CD3^lo Thy1.2⁺CD44⁻CD25⁺) from B6 and DKO thymi. <b>B.</b> Induction of p-AKT (pS473) was measured in DN3 (CD4⁻CD8⁻Thy1.2⁺CD3^lo Thy1.2⁺CD44⁻CD25⁺) from B6 and DKO thymi. <b>C.</b> Bulk thymocytes were stimulated with 10 nM SDF1α for 0, 1, 2, 3 or 5 minutes and the induction of p-ERK (pT202/pY204) was measured in DN3 (CD4⁻CD8⁻Thy1.2⁺CD3^lo Thy1.2⁺CD44⁻CD25⁺) from B6, 1KO, 3KO and DKO thymi. Data are representative of between 3 and 7 independent experiments. * represents a significant statistical comparison between B6 and DKO. # represents a significant statistical comparison between B6 and 1KO. */# p<0.05.