Glutaredoxin represses transcriptional and developmental responses to nitrate in roots.

Glutaredoxins (GRXs) are small oxidoreductase enzymes that can reduce disulfide bonds in target proteins. The class III GRX gene family is unique to land plants, and has 21 class III GRXs, which remain largely uncharacterized. About 80% of class III GRXs are transcriptionally regulated by nitrate, and several recent studies have suggested roles for these GRXs in nitrogen signaling.