Extension of Chronological Lifespan by Hexokinase Mutation in Kluyveromyces lactis Involves Increased Level of the Mitochondrial Chaperonin Hsp60
Figure 3
Oxidative stress analysis in rag5Δ strain. (a) Evaluation of stress resistance of the long-lived strain by inducing ROS damage with 5 and 20 μM menadione. (b) Evaluation of ROS accumulation in 1 day cultures of wt and rag5 cells challenged with 20 μM menadione for 2 hours. The results were the mean of at least three independent experiments with s.d. <5%. (c, d) Measurement of cellular ROS. FACS analysis of aging cells stained for cellular ROS using DHR123 (c) and cellular superoxide using DHE (d) are shown. The mean fluorescent intensity of three independent experiments is plotted ± one standard deviation.** value from a Student’s t-test, <0.01, *** value from a student’s t-test, <0.001. (e) Total glutathione levels. GSH levels were normalized with respect to the protein total content of the samples. The results are the mean of three independent experiments with s.d. <5%. (f) Northern analysis of CTA1, CTT1, SOD1, and SOD2 in wt strain and in rag5Δ strain. Total mRNAs were prepared as described in Section 2 from cells grown on YPD medium for 24 and 48 hours. Lines 1: wt, 24 h; line 2: rag5Δ, 24 h; lines 3: wt, 48 h; line 4: rag5Δ, 48 h. The experiment showed is representative of three independent experiments, repeated with similar results.
