Figure 2.

Blue light, but not red light pulses, evoke photocurrents in Chronos-expressing CHO cells. Voltage clamp, whole cell recordings of a Chronos-expressing CHO cell (a) when stimulated with (b) blue light and (c) red light, both at increasing illumination power densities. The horizontal blue and red lines above the voltage-clamp traces represent 5 ms long red and blue LED pulses incident on the patched cell respectively. (d) The average induced photocurrent of Chronos-expressing cells increased with the blue LED power density, but remained zero with increased red LED power density. The graph shows the average currents measured in N  =  4 cells, across 16 trials for blue light, and 13 trials for red light. Vertical lines represent the standard error of the mean (S.E.M); S.E.M values for the red light data series are too small to be seen on this scale. The blue shaded area represents the power densities used to photostimulate Chronos-expressing brain slices; the red shaded area represents the range of power densities used to image CaSiR-1 fluorescence in the brain slice preparations.