Figure 4.

Mec1-dependent activation of Rad53 in response to cadmium. (A) Experimental conditions were as in Figure 3A. Immunoblots were analyzed with polyclonal antibodies directed against Rad53. As a control, Rad53 from cells treated with 0.1% MMS for 30 min was analyzed. (B and C) Cells were grown as described in Figure 3A, incubated with 1 mM cadmium for 30 min, and analyzed by immunoblotting by using polyclonal antibodies to Met4 or Rad53. Strains used were mec1Δ (PY1164), tel1Δ (PY1161), rad53Δ (PY1117), and met4Δ (PY1123). mec1Δ and rad53Δ mutants were kept alive by a high-copy plasmid containing the RNR1 gene.