Figure 3.

Inhibition of LHCII and D1 protein phosphorylation by thiol reagents. Thylakoids isolated from dark-adapted leaves were incubated in darkness without (white bar) and with DTT (dark gray bars) or NEM (light gray bars) for 10 min. Thereafter, in vitro protein phosphorylation was initiated. In experiments indicated by hatched bars, the thylakoid membranes were first incubated with 2 mM DTT, which was subsequently washed out by pelleting the thylakoids and resuspending them in the same buffer either without thiol reagents (hatched white bars) or with various concentrations of NEM (hatched gray bars), and incubated in darkness for 10 min before the phosphorylation assay. The concentrations of DTT and NEM are indicated under (or above) the bars. The phosphorylation levels of the D1 and LHCII proteins were analyzed as described in Fig. 2. Results are means ± SD, n = 2–4.