2.4. Luciferase-based ATP assay

Luminescent ATP detection assay kit (ab113849: Abcam, Cambridge, MA, USA) was used to measure ATP produced by DRG neurons. In brief, cultured DRG neurons and ATP standard dilution series were prepared. D-Luciferin and firefly luciferase reagents were added to the reaction mix, stirred and incubated for 10 min. Luminescence from luciferase activity was recorded using the Glomax multi-detection system (Promega, Wisconsin, USA). A standard curve was plotted and luminescent units from each sample were interpolated to calculate the absolute ATP concentration per mg of total protein lysate. Luminescence from oligomycin- and 2-DG-treated neurons was measured after adjusting to their basal levels.