Fig. 5

NMNAT2 loss impairs glycolysis in distal axon presynaptic varicosities. A Experimental and live imaging timeline. B Schematic diagram of the Syn-ATP sensor configuration and the treatment. Syn: synaptophysin, mCh: mCherry, Luc: luciferase. C Representative Syn-ATP luminescence and fluorescence images of distal axon varicosities under basal and oligomycin-treatment conditions from DIV8 ctrl, KO, and KO neurons supplemented with NAD⁺ (KO + NAD⁺). Scale bar, 5 μm. D pH-corrected L/F (Luminescence/Fluorescence) ratio representing relative presynaptic ATP levels measured by the Syn-ATP sensor in mCherry positive varicosities of distal axons of DIV8 ctrl, KO, and KO + NAD⁺ neurons. Numbers (neurons imaged) and statistics: 78 ctrl, 77 KO, and 48 KO + NAD⁺ under basal conditions; 67 ctrl, 68 KO, and 48 KO + NAD⁺ under oligomycin-treated conditions. Ctrl and KO were from 5 independent experiments, and KO + NAD⁺ was from 2 independent experiments. Kruskal–Wallis test with Dunn's multiple comparisons test was used. All above data represents mean ± SEM, ** p = 0.004, ****p < 0.0001. In the NAD⁺ treated KO group, the difference between basal and oligomycin treatment conditions is marginal to significance, p = 0.0537