Fig. 3.

Metabolome analysis reveals altered oxidative tolerance of solitary and gregarious locusts. (A) PCA trajectory analysis of altered metabolites in gregarious locusts (blue point) and solitary locusts (orange point) in response to 0.25 and 1 h of flight treatment. Bar lines indicate SEM of PC1 and PC2. Five biological replicates for each flight treatment time point, and each replicate contains six locusts. Content changes of (B) TAG and (C) PE and PC during flight. Heat-map signal indicates log₂ fold-change value relative to the median expression level within the gregarious and solitary groups, respectively. Yellow and blue signals represent higher and lower levels, respectively. The dendrograms generated by the hierarchical clustering of metabolites are also provided. TAG: triacylglycerol, PC: glycerophosphocholine; PE: glycerophosphoethanolamine (n = 5 replicates, six locusts per replicate). (D) Pathway topology analysis of altered metabolites after flight treatment. Only pathways with P < 0.05 are shown (Fisher’s exact test). (E) Content changes in purine intermediate metabolite levels and (F) GSH during flight (n = 5). (G) H₂O₂ alterations in response to flight (n = 8). Time points are shown as 0.25- and 1-h flight treatment, each time point is compared to rest condition samples, Student’s t test. (H) GSH/GSSG and H₂O₂ alterations in response to paraquat treatment in the flight muscles (n ≥ 7, Student’s t test). (I) Flight performance measurement in response to paraquat treatment (n ≥ 17 individuals, Mann–Whitney U test). Each dot represents a single individual. Paraquat (2 µL) was injected at concentrations of 4, 20, and 100 mmol⋅L⁻¹ for 48 h. Locusts injected with saline (2 µL) served as the negative control. Different concentration samples are compared to the negative control. The data are shown as mean ± SEM, *P < 0.05, **P < 0.01, and n.s, not significant. G and S represent gregarious and solitary locusts, respectively.