Figure 7.

Distribution of γ-H2AX near the telomere. (A) γ-H2AX ChIP at subtelomeric regions of chromosome III (left and right) in the absence of exogenous DNA damage normalized by the γ-H2AX ChIP signal at CEN8. The black boxes denote the positions of telomere sequences. The location of HML is indicated by the gray box. (B) cdc13-1 mutant cells were grown at 25°C in log phase and shifted to 37°C at the same time when HO was induced by adding galactose into the culture. γ-H2AX near the telomere, TEL03L, as well as ∼20 kb to the right of the HO-induced DSB at MAT (gray symbols) were examined by ChIP and normalized to the signal at CEN8. Samples were collected before temperature shift and HO induction (diamonds) and at 1 (squares), 2 (triangles), and 4 (circles) h. The arrowhead indicates the location of HO-induced DSB. The black box denotes the position of TEL03L. The location of HML is indicated by the gray box. (C) The constitutive level of γH2AX near TEL03L was examined in the sir4Δ strain (triangles) and in the yku80Δ strain (squares) by ChIP. The black box indicates TEL03L. (D) The constitutive level of γH2AX near TEL03L and TEL03R was examined in G1-arrested cells (diamonds) after α-factor arrest and in G2-arrested cells (squares) after nocodazole treatment. γ-H2AX was also examined in the G1-arrested tel1Δ strain (triangles). The black boxes indicate TEL03L and TEL03R. Error bars represent SEM.