Redox-mediated kick-start of mitochondrial energy metabolism drives resource-efficient seed germination

摘要: Seeds preserve a far developed plant embryo in quiescent state. Seed metabolism relies on stored resources and is reactivated to drive germination when the external conditions are favorable. Since switchover from quiescence reactivation provides remarkable case of cell physiological transition we investigated earliest events energy redox Arabidopsis seeds at imbibition. By developing fluorescent protein biosensing intact seeds, observed ATP accumulation oxygen uptake within minutes, indicating rapid activation mitochondrial respiration, which coincided with sharp an oxidizing more reducing thiol environment matrix. To identify individual operational switches, captured fast release metabolic organello devised quantitative iodoacetyl tandem mass tag (iodoTMT)-based proteomics. The state across all Cys peptides was shifted toward reduction 27.1% down 13.0% oxidized thiol. A large number (412) were switched, representing central pathways metabolism, including respiratory chain each enzymatic step tricarboxylic acid (TCA) cycle. Active site glutathione reductase 2, NADPH-thioredoxin a/b, thioredoxin-o1 showed strongest responses. Germination lacking those proteins associated markedly enhanced respiration deregulated TCA cycle dynamics suggesting decreased resource efficiency metabolism. aged strongly impaired. We global operation switches that required for optimal usage stores by mitochondria efficient germination.