English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

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 in aox1a/pgr5 than that in the other genotypes at the early growth stage, while the leaf area ratio was higher in aox1a/pgr5 . We assessed detailed mechanisms in relation to NAR . In aox1a/pgr5 , photosystem II parameters decreased under HL, whereas respiratory O 2 uptake rates increased. Some intermediates in the tricarboxylic acid (TCA) cycle and Calvin cycle decreased in aox1a/pgr5 , whereas γ-aminobutyric acid (GABA) and N-rich amino acids increased in aox1a/pgr5 . Under HL, AOX may have an important role in dissipating excess reductants to prevent the reduction of photosynthetic electron transport and imbalance in primary metabolite levels.

international journal of molecular sciences

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