FIGURE 4.

DNA-protein complexes formed by yKu and Nej1 in EMSAs. Formation of DNA-protein complexes by yKu and Nej1 with a 200-bp DNA duplex with blunt ends (38 nm) was detected in EMSAs as described under “Experimental Procedures.” A, lane 1, no protein; lane 2, 3 nm yKu; lane 3, 3 nm yKu and 6 nm Nej1; lane 4, 3 nm yKu and 12 nm Nej1; lane 5, 3 nm yKu and 25 nm Nej1; lane 6, 6 nm Nej1; lane 7, 12 nm Nej1; lane 8, 25 nm Nej1. B, DNA-protein complexes formed by yKu (3 nm; lanes 2–4 and 6–8) and Nej1 (25 nm; lanes 2–4, 6, and 7), either alone or in combination, were incubated with anti-yKu (lanes 3 and 4) or anti-Nej1 (anti-CBP, lanes 7 and 8) antibodies as indicated. Lanes 1 and 5, no protein.