Abstract
In plants, glutathione (GSH) is synthesized mainly by photosynthesis. GSH synthesized in leaves translocates to other organs for physiological and developmental regulations. The wild-type Arabidopsis showed a specific pattern of GSH accumulation in roots, especially in root apices and hairs. To address whether this pattern is associated with GSH function, GSH was applied to the plant, resulting in an increase in the root-hair number. These suggest that GSH acts positively in root hair formation. Investigating several mutants having an aberration of root-hair formation revealed an association of the pattern with the root-hair-forming position, leading to finding the mutant that lacks the root-hair-forming response to GSH but still has the specific pattern similar to the wild-type. This mutant proved defective in the positive regulator CAPRICE (CPC) of root hair formation. Overexpressing CPC disrupted the pattern of GSH accumulation, suggesting that CPC and GSH cooperatively function in root-hair formation.
