Effects of IL-7 (10 U), IL-15 (10 U), and IL-2 (100 U) on the DNA binding of c-Myc and Max to the E box in SeAx cells. Lanes 1 to 3, no IL, lanes 4 to 6, IL-7; lanes 7 to 9, IL-15; lanes 10 to 12, IL-2. The individual DNA binding proteins were identified by specific antibodies (see Max-Ab and c-Myc-Ab bands). C1, c-Myc/Max heterodimer; C2, IL-stimulated E-box binding factor-1 (ISEBF-1); C3, IL-stimulated E-box binding factor-2 (ISEBF-2). Lanes 1, 4, 7, 10, no antibody (Ab); lanes 2, 5, 8, 11, Max Ab; lanes 3, 6, 9, 12, c-Myc Ab.