Wld^S requires N70 and Nmnat1 biosynthetic activity for maximal protection of severed axons in vivo. UAS-regulated versions of Wld^S variants were expressed in OR22a⁺ ORNs with OR22a-Gal4, axons were severed, and the number of remaining intact GFP⁺ axons was scored at the time points indicated. Two to four independent insertion lines were tested for each UAS-regulated Wld^S variant molecule (Fig. S1, available); n ≥ 10 for individual lines; data were subsequently pooled and are presented here. For Nmnat1, **, P < 0.01 and ***, P < 0.001 (Nmnat1 vs. Wld^S at corresponding time points). For Wld^S, **, P < 0.01 (day 0 vs. day 30). Error bars represent SEM.