Figure 5.

Effect of Fasting on Protein Cysteine-Residue Oxidation and Survival

(A) Survival of young (7 days) control and catalase-overexpressing flies during fasting. Arrow indicates where cohorts are sampled (24-hr treatment).

(B) Distribution of cysteine peptides plotted against redox states of the cysteine residues for control flies after 24-hr fasting. Shown is the mean for the relative numbers of cysteine residues in each 5% quantile of the five biological replicates. The dashed line is the curve for the untreated control (cf. Figure 2B) cohort.

(C) Oxidation state of cysteine residues present in control flies upon 24-hr fasting compared to untreated cohorts. Dotted line slope = 1, while the continuous line is the best fit to the data. Each symbol represents a cysteine residue identified in at least three biological replicates of both the control untreated as well as the fasted cohort. Red symbols identify cysteine residues (n = 252) with p < 0.05 (non-paired, two-tailed Student’s t test), while blue symbols (n = 200) indicate a high-stringency significance (Benjamini-Hochberg test). Total unique peptides = 387.

(D) Distribution of cysteine peptides plotted against redox states of the cysteine residues for catalase-overexpressing flies after 24-hr fasting. Shown is the mean for the relative numbers of cysteine residues in each 5% quantile of the five biological replicates. Dashed line is the distribution for untreated catalase-overexpressing flies on control food.

(E) Oxidation state of cysteine residues in catalase-overexpressing flies upon 24 hr fasting against untreated cohorts. Dotted line slope = 1, while the continuous line is the best fit to the data. Each symbol represents a cysteine residue identified in at least three biological replicates of both the untreated and fasted cohorts. Red symbols identify cysteine residues (n = 96) with p < 0.05 (non-paired, two-tailed Student’s t test). Blue symbols (n = 51) indicate high-stringency significance assessed (Benjamini-Hochberg test). Total unique peptides = 440.

(F) Oxidation state of cysteine residues present upon 24-hr fasting in catalase-overexpressing flies plotted against control flies. Dotted line slope = 1, while the continuous line is best fit to the data. Each symbol represents a cysteine residue that was identified in at least three biological replicates of both the fasted control and catalase-overexpressing flies. Red symbols identify cysteine residues (n = 13) p < 0.05 (non-paired, two-tailed Student’s t test). Total unique peptides = 601.

See also Figures S5–S8.