Research Paper Volume 9, Issue 4 pp 1153—1185

The age- and sex-specific decline of the 20s proteasome and the Nrf2/CncC signal transduction pathway in adaption and resistance to oxidative stress in Drosophila melanogaster

Figure 6. Tissue-specific differences of the adaptive proteolytic capacity, and age-dependent changes in basal activity, of the 20S proteasome in females. Body segments collected from female progeny of the Actin-GS-255B strain crossed to the w[1118] strain were used as controls, or were pretreated with either 10µM or 100µM hydrogen peroxide. Individual proteolytic capacity of the 20S proteasome (caspase/peptidyl glutamyl-peptide hydrolyzing-like activity, trypsin-like, and chymotrypsin-like activity) was measured in the abdomen, head, and thorax. (A-C) Abdomen isolated from 3 day old (pink) and 60 day old (black) females following hydrogen peroxide pretreatment. (A) Caspase-like activity. (B) Trypsin-like activity. (C) Chymotrypsin-like activity. (D-F) Head isolated from 3 day old (pink) and 60 day old (black) females following hydrogen peroxide pretreatment. (D) Caspase-like activity. (E) Trypsin-like activity. (F) Chymotrypsin-like activity. (G-I) Thorax isolated from 3 day old (pink) and 60 day old (black) females following hydrogen peroxide pretreatment. (G) Caspase-like activity. (H) Trypsin-like activity. (I) Chymotrypsin-like activity. Error bars indicate the standard error of the mean (S.E.M) values. * P <0.05, ** P <0.01, *** P < 0.001, relative to the young female control using one-way ANOVA. Statistical significance is shown with pink asterisks (pink *) for young females and black asterisks (black *) in aged females.