The concentration of intracellular chloride is altered by KIF4 mutation in a PARP1-TrkB dependent manner in hippocampal primary neurons. (A) Calibration of ClopHensorN fluorescence in the hippocampal neurons. Scale bar, 20 µm. Statistical results exhibited green/red fluorescence ratio decreasing with intracellular chloride concentration gradient. Data are presented as mean ± SEM (n = 30, 3 independent experiments). (B) ClopHensorN fluorescence images of hippocampal culture neurons (DIV 18) demonstrating a higher intracellular chloride concentration in the mutant neurons and the NAD or ANA-12 could rescue this phenotype. Scale bar, 20 µm. Data are presented as mean ± SEM (n = 30, 3 independent experiments). ***P < 0.001, ****P < 0.0001 (two-way ANOVA).