Figure 6.

Dose‐ and time‐dependent tuning of non‐photochemical quenching (NPQ) capacity via chemical induction of ZEP3 expression.

An inducible ZEP3 Phaeodactylum strain (zep3‐2 + iZEP3) was created via complementation of the zep3‐2 mutant with a construct containing the native ZEP3 gene under the control of a β‐estradiol‐inducible synthetic promoter.

(a) The NPQ of the iZEP3 strain and WT was measured with an IMAGING‐PAM at different β‐estradiol concentrations after 24 h.

(b) The NPQ of the iZEP3 strain was measured over 48 h at 1000 nm β‐estradiol. Cells were incubated and assayed in 24 well plates with 2 ml of f/2 medium to which was added 2 μl of β‐estradiol at the needed concentration or 2 μl of ethanol as a vehicle control. Points are averages with error bars representing one standard deviation of biological replicates (n = 3). Asterisks represent statistically significant differences between WT and the iZEP3 strain, tested via unpaired t‐tests at each timepoint with Holm‐Šídák's multiple comparison method (*P < 0.05, **P < 0.005, ***P < 0.0005).