Limited TORC1 signaling in the H3K37A mutant selectively induces necrosis. (A) Wild-type (BY4741), tco89Δ, H3WT, and H3K37A cells were grown to log phase before mock treating or treating with 25 nM rapamycin for 24 hours. Viability was determined by staining cells with Annexin V and propidium iodide and analyzing by flow cytometry. (B) Mock-treated and rapamycin-treated H3WT and H3K37A mutants from (A) were visualized by confocal microscopy. Scale bar represents 10 μm. (C) H3WT and H3K37A mutants were combined with an atg6Δ to prevent autophagy and then spotted to control YPD or YPD + 25 nM rapamycin plates. Plates were incubated at 30°C for 4 days. (D) H3WT, H3K37A, and the mitochondrial-deficient (ρ-) derivative strains from each background were spotted to control YPD, YP containing 3% glycerol and YPD containing 25 nM rapamycin plates. The YPD and YP + 3% glycerol plates were incubated at 30°C for 3 days while the YPD + 25 nM Rap plates were incubated at 30°C for 7 days. PI, propidium iodide; rap, rapamycin.