Figure 4.
The Rad9 BRCT2 domain is required for G1 checkpoint signalling. (A) Analysis of Rad9 phosphorylation in response to bleomycin. G1-arrested cells were treated as in Fig 1A and analysed by anti-Rad9 immunoblotting. (B) Analysis of Rad9 phosphorylation in response to ultraviolet-irradiation. G1-arrested strains were treated with 50 J/m2 ultraviolet radiation and then held in G1 for the indicated time period. (C) Analysis of Rad53 phosphorylation in response to IR and UV radiation. G1-arrested cells were irradiated with the indicated doses of X-ray or UV irradiation and then held in G1 for 30 min. αF, alpha factor; Bleo, bleomycin; IR, ionizing radiation; UV, ultraviolet; WT, wild type.