Figure 1. Scheme of chloroplast redox regulation in the stroma.
A schematic representation of two reduction pathways (A), FNR/NTRC and
FTR/Trx under different light availability, and (B) oxidation pathway
under dark is shown. (A) Under high light intensity, the FTR regulatory
system dominantly reduces thiol-regulated target enzymes. Under limited
light availability, the NTRC system mainly functions. (B) Under dark,
2CP mediates oxidizing the target enzymes. More details can be found in
Section 2. The arrows indicate the flow of reducing equivalents, with
blue representing reduction and pink representing oxidation.
Abbreviations: ETC, Electron transport chain; FNR, ferredoxin-NADP+
reductase; FTR, ferredoxin-thioredoxin reductase; NTRC, NADPH-dependent
thioredoxin reductase C;
2CP, 2 Cys-peroxiredoxin