Fig. S3.

Singlet oxygen-mediated signaling in lincomycin-treated flu seedlings. (A) Light-grown flu seedlings were transferred to the dark for 8 h and re-exposed to light for 24 h (8 hD/24 hL). Thirty minutes before reillumination seedlings were sprayed with or without 5 mM lincomycin. Control flu seedlings kept under continuous light (LL) were sprayed with or without lincomycin in the light 24 h before images were taken. (B) Transient Chl fluorescence images taken from seedlings shown in A reveal a similar strong photoinhibition of PSII in mock- and lincomycin-treated flu seedlings subjected to the dark-to-light shift, but not in LL seedlings. (C) Singlet oxygen-mediated cell death as revealed by trypan blue staining occurs only in flu seedlings after a dark-to-light shift and is not affected by lincomycin.