Figure 4.

Protection in raw mutants is not sensitive to levels of Nmnat enzyme. A, Endogenous Nmnat levels in neuropil are increased in hiw mutants (noted with yellow brackets), however are not detectably changed in raw mutants (raw^dcp-1). B, Quantification of the relative levels of Nmnat protein in the neuropil regions of WT, hiw^ΔN and raw^dcp-1 animals. C, Example axons from m12-Ga4 expressing neurons, labeled by coexpression of UAS-mCD8::GFP, UAS-Dcr2 and UAS-nmnat-RNAi, shown 20 h after injury. D, Quantification of axonal degeneration in different time points for the noted genotypes. Comparing to WT animals (black line), knock-down of nmnat by RNAi (green line) modestly promotes axonal degeneration. Although knock-down of nmnat in the hiw mutant background significantly rescues the axonal protection phenotype in hiw mutant (compare pink line to blue line), knock-down of nmnat in raw^dcp-1 mutant background only modestly changes the axonal protective effect of raw^dcp-1 (compare red line to blue line). Scale bar, 20 μm. Error bars indicate SEM. ****p < 0.0001; ns (p = 0.5314), one-way ANOVA test; n = 5 animals per genotype in B, n ≥ 25 axons from 5 animals per condition in D.