Mitochondrial AOX Supports Redox Balance of Photosynthetic Electron Transport, Primary Metabolite Balance, and Growth in Arabidopsis thaliana under High Light.

ABSTRACT: When leaves receive excess light energy, excess reductants accumulate in chloroplasts. It is suggested that some of the reductants are oxidized by the mitochondrial respiratory chain. Alternative oxidase (AOX), a non-energy conserving terminal oxidase, was upregulated in the photosynthetic mutant of Arabidopsis thaliana, pgr5, which accumulated reductants in chloroplast stroma. AOX is suggested to have an important role in dissipating reductants under high light (HL) conditions, but its physiological importance and underlying mechanisms are not yet known. Here, we compared wild-type (WT), pgr5, and a double mutant of AOX1a-knockout plant (aox1a) and pgr5 (aox1a/pgr5) grown under high- and low-light conditions, and conducted physiological analyses. The net assimilation rate (NAR) was lower

SUBMITTER: Jiang Z 

PROVIDER: S-EPMC6628045 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature