Fig. 3. Ethylene biosynthesis pathway and gene expression regulation during Arabidopsis thaliana seed germination.
a Ethylene biosynthesis as discovered by (Yang and Hoffman 1984). Key step during seed germination is the conversion of ACC to ethylene via ACC oxidases (Linkies et al. 2009; Matilla and Matilla-Vázquez 2008).
b and c Relative transcript expression results obtained by eNorthern analyses of data from the BAR expression browser at www.bar.utoronto.ca (Toufighi et al. 2005) based on experiments for non-dormant, non-stratified after-ripened wild type seeds (Nakabayashi et al. 2005; Preston et al. 2009), cold-stratified wild type seeds (Yamauchi et al. 2004), ABA-treated wild-type and GA-treated ga1-3 seeds (RIKEN transcriptome sets). Shown are relative transcript abundance ratios based on seed imbibition time in the light (24h / 0h), ABA treatment (ABA / control at 24h), cold stratification (4ºC / 22ºC after 96h imbibition in darkness), and GA treatment (GA / control at 6h). Abbreviations: ACC= 1-aminocyclopropane-1-carboxylic acid, MTA= methylthioadenosine, MTR= methylthioribose, SAM= S-AdoMet.