Figure 1.

Nutritional and Organ-Specific Plasticity of Different Tracheal Subsets

(A–C) Representative tracheation of the ventral nerve cord (VNC) (A), body wall (B), and gut (mid-hindgut, C) in well-fed larvae (8% yeast).

(D–F) A mild nutrient restriction (2% yeast) does not affect CNS (D) or body wall (E) tracheae, but leads to reduced tracheal terminal growth in the gut (mid-hindgut, F).

(G–I) Severe nutrient restriction (0.8% yeast) does not affect CNS tracheae (G), but leads to reduced coverage of both body wall (H) and gut (I, mid-hindgut). For body wall: p < 0.001 (8% versus 0.8%), p = 0.004 (2% versus 0.8%). For mid-hindgut: p < 0.0001 (8% versus 0.8%), p < 0.0001 (8% versus 2%), and p < 0.0001 (2% versus 0.8%). n = 10–24/set.

(J) Representative gut tracheation (mid-midgut) of a 7-day-old adult fly reared on a nutritious (8% yeast) diet both during larval and adult stages.

(K) Representative tracheation of the same intestinal region in an age-matched fly subject to an identical dietary regime as an adult, but exposed to a restricted diet (0.8% yeast) during larval life. Reduced branching is apparent.

(L) Increased tracheation of the same region in a representative adult fly reared under standard conditions and exposed to 9% sucrose for 7 days.

Quantifications of the adult phenotypes (J to L) are displayed below these panels. p = 0.001 (well-fed – larval restriction) and p < 0.0001 (balanced – adult imbalance), n = 17–33/set. Scale bars, 10 μm in all images except for (B), (E), and (H), 100 μm. See also Figures S1 and S2. Color coding for this and subsequent Likert levels are displayed as follows: red (strongly reduced), orange (reduced), gray (unchanged), light blue (increased), and dark blue (strongly increased). The mean (circled) is also displayed. See Experimental Procedures for additional information.