TGF-β Signaling Mediates Food Suppression of Hyperoxia Avoidance

(A–E), (H), (I) In all panels, dotted lines indicate aerotaxis in the presence of a small amount of bacterial food. (A) Aerotaxis of wild-type N2 animals. (B) Aerotaxis of daf-7 mutants. (C) Aerotaxis of daf-3 mutants. (D) Aerotaxis of daf-7; daf-3 double mutants. (E) Aerotaxis of daf-3 npr-1 double mutants. (F–G) daf-7::GFP expression in ASI was reduced in a tax-4 mutant. Anterior is to the left. (H) Aerotaxis of tax-4; kyIs342 animals, which bear a transgene that rescues tax-4 in URX, AQR, and PQR, but not in ASI or other neurons. (I) Aerotaxis of tph-1; daf-3 double mutants. For (A–E), (H), and (I), asterisks denote distributions different by chi-square analysis at p < 0.01 from the same genotype without food. n ≥ 3 assays per genotype and condition, 80–100 animals/assay. Error bars denote SEM. (J) Hyperoxia avoidance index as defined in Figure 1. Asterisks, values significantly different from the same genotype without food at p < 0.05 by t test. In the absence of food, no strain is different from N2 controls by Dunnett test. In the presence of food, daf-7, daf-3 npr-1, and tph-1; daf-3 are different from N2 at p < 0.01 and tax-4; kyIs342 different from N2 at p < 0.05 by Dunnett test. Error bars denote SEM.