Calcium imaging demonstrates colocalization of calcium influx and extrusion in fly photoreceptors -- Data Supplement - Supplemental Data -- Proceedings of the National Academy of Sciences

Supplementary material for Oberwinkler and Stavenga (2000) Proc. Natl. Acad. Sci. USA 97 (15), 8578-8583.

QuickTime Video Movie 1.
Movie showing the Ca²⁺ influx and diffusion during light stimulation of a dark-adapted fly photoreceptor cell. The images were taken at a speed of 480 images per second and show the raw fluorescence intensity in false color coding. A photoreceptor cell injected with the Ca²⁺ indicator OG5N (the same cell as in Fig. 1) was dark adapted for at least 1 min and stimulated with strong laser light that was used for measuring the fluorescence. This experiment was repeated five times, and the resulting image sequences were averaged. At the beginning of the stimulation, only the region corresponding to the rhabdomere shines up strongly, showing that Ca²⁺ influx takes place only there. Subsequently, the increase in fluorescence spreads into the cell body, indicating that Ca²⁺ diffuses from the rhabdomere into the cell body. To facilitate viewing, the movie has been slowed down by a factor of 30. The duration of the measurement shown in the movie therefore corresponds to 204 ms.