Figure 6
From: Light- induced electron transfer and ATP synthesis in a carotene synthesizing insect
Tetrazolium (MTT) reduction by orange aphid extract.
100 µl of tetrazolium solution (1 mM in water) were placed on a glass slide in which 10 µl of orange aphid extracts were added. The system was irradiated by visible light (A) for 30 min or kept in dark (B). Then, the medium was delicately washed out. Top: The photos show the border of the spots where the formazan precipitation is more intense. Unambiguously, an increase of MTT reduction, measured as formazan precipitation on the glass, is observed under light (A). Middle: higher magnification of the photograph above. Bottom: The light exposure of strongly pigmented ovarioles in presence of MTT (1 mM in water) is compared with white/pale ovarioles in the same conditions as above. Produced formazan by orange or white aphid extract (100 µg protein) under light or kept in dark was measured after solubilization in acid/ethanol (C and D). The representations are the mean of three separate experiments.
