Figure 2.

Widespread transcription induction defects in old cells. Whole life span imaging of cells expressing the indicated reporter constructs. (A–E) Maximal GFP induction rate was determined over a sliding window of 10 min for each division for 10 cells per analyzed strain. For statistical analysis, the data points of young cells (all cell divisions except the last six divisions before cell death), old cells (divisions −4 to −6 before cell death), and very old cells (last three complete divisions before cell death) were combined (A40278, A40279, A40276, A40277, and A40280). (F) Cells (A39859) were grown for 2 h (young) or 24 h (old) on microfluidic chips, and MET25-mCherry was induced by switching to methionine-free medium. Only cells that had undergone a minimum of eight cell divisions were considered old. (*) P < 0.01 (Mann-Whitney test).