FIG. 4.

H134R-ChR2–expressing animals show less spike frequency adaptation than ChR2-expressing animals. A: light-evoked large EJPs in m6 in response to constant blue light stimulation of animals expressing ChR2 (top) or H134R-ChR2 (bottom) in motor neurons under control of OK371-GAL4. Instantaneous EJP frequency is shown above each trace. Note dashed line at 20 Hz in both panels. B: pooled data showing the decay of EJP frequency (means ± SE) as a function of genotype and stimulation rhythmicity. *Significant differences from ChR2 constant light data at each time point (P < 0.05, ANOVA with Bonferroni post hoc test); color of asterisk indicates which data set is being compared. Blue light pulses were 470 nm and 300 μW/mm² for all experiments. n for each data set is indicated on the histogram bar.