Research Paper Volume 2, Issue 10 pp 678—690

Intracellular protein glycosylation modulates insulin mediated lifespan in C. elegans


Figure 4. Inactivation of O-GlcNAc cycling enzymes only affects a subset of functions regulated by the insulin-like signaling pathway. (A) The oga-1(ok1207) mutant is resistant to oxidative stress (100mM paraquat for 9 hrs). Notably, the oxidative stress resistance in daf-2(e1370) mutant is significantly reduced in the daf-2(e1370); ogt-1(ok1474) double mutant, suggesting that protein O-GlcNAc modification contributes to the oxidative resistance of the daf-2 mutant. (B) The long-lived oga-1(ok1207) mutant is sensitive to heat stress (35°C), unlike the long-lived daf-2 (e1370) mutant. (C) oga-1 and ogt-1 mutants have normal developmental timing [from hatch to the fourth larval molt] at 20°C. The daf-2 mutant has delayed post-embryonic development, and this delay is unaffected by loss of O-GlcNAc modification in the daf-2; ogt-1 double mutant. (D) oga-1 and ogt-1 mutants generate normal numbers of offspring while the daf-2 mutant has reduced fecundity at 20°C. The reduced fecundity in the daf-2 mutant is not rescued by loss of O-GlcNAc modification in the daf-2; ogt-1 double mutant. Asterisks above bars denote statistically significant differences from wild type (* p < 0.05 and ** p < 0.01); while asterisks above solid lines connecting two genotypes denote statistically significant differences between those genotypes.