REC8 but not sister chromatid cohesion is required for pairing. (A) Wild-type cells with homologous TEL5 dots (A16366, ■), or with homologous URA3 dots (A6946, ▴), or with homologous CEN5 dots (A16362, ·), rec8Δ cells with homologous TEL5 dots (A16535, blue rectangle), or with homologous URA3 dots, (A16538, blue triangles), or with homologous CEN5 dots (A16537, blue circles), and wild-type cells with nonhomologous CEN5/LEU2 dots (A16360, ○), all deleted for NDT80, were assayed for pairing as described in Figure 1A. (B) Wild-type cells with homologous LYS2 dots (A9828, ■), or with homologous LEU2 dots (A5111, ▴), rec8Δ cells with homologous LYS2 dots (A16108, blue rectangles), or with homologous LEU2 dots, (A16131, blue triangles), and wild-type cells with nonhomologous LYS2/LEU2 dots (A11474, □), all deleted for NDT80, were assayed for pairing as described in Figure 1A. (C–E) Wild-type (A9828, ■) or cdc6-mn cells with homologous LYS2 dots (A10735, ▴) and wild-type cells with nonhomologous URA3/LYS2 dots (A9829, □), all deleted for NDT80, were induced to sporulate to assayed pairing as described in Figure 1A (C) or DNA content by flow cytometry analysis (D and E). (F–H) Wild-type cells with homologous URA3 dots (A6946, ■), cdc6-mn cells with homologous URA3 dots (A10404, ▴), wild-type cells with nonhomologous URA3/LYS2 dots (A9829, □), all deleted for NDT80, were induced to sporulate to assayed pairing as described in Figure 1A (F) or DNA content by flow cytometry analysis (G and H). (I) Wild-type cells with homologous LEU2 dots (A5111, ■), rec8Δ cells with homologous LEU2 dots (A16131, ▴), cdc6-mn cells with homologous LEU2 dots (A16533, ·), rec8Δ cdc6-mn cells with homologous LEU2 dots (A16460, ♦), and wild-type cells with nonhomologous LEU2/LYS2 dots (A11474, □), all deleted for NDT80, were assayed for pairing as described in Figure 1A. Note that the time courses shown in I and J were performed at the same time, and the nonhomologous dot controls are shown in both experiments. (J) Wild-type cells with homologous LYS2 dots (A9828, ■), rec8Δ cells with homologous LYS2 dots (A16108, ▴), cdc6-mn cells with homologous LYS2 dots (A10735, ·), rec8Δ cdc6-mn cells with homologous LYS2 dots (A16446, ♦), and wild-type cells with nonhomologous LEU2/LYS2 dots (A11474, □), all deleted for NDT80, were assayed for pairing as described in Figure 1A.