In >6-months-old mice but not 3-months-old mice, conditional CK2β-deficient mice exhibited impairment of neural transmission, as reflected by lowered miniature endplate potentials and currents in comparison with wild-type litters. The following electrophysiological recordings are presented: (A) membrane resistance, (B) miniature endplate potential amplitudes, (C) miniature endplate current amplitudes, (D) frequency of miniature endplates, (E) endplate potential amplitudes, (F) endplate current amplitudes, (G) decrement of endplate potential amplitude at 5 Hz. (*** p < 0.001; ** p < 0.01; unpaired two-tailed Student’s t-test; mice per genotype ≥ 3).