A T-DNA insertion mutant of At4g11180 (DP1). A, Coexpression and accumulation network between lignans (blue) and putative DP genes (orange). Positive correlations above threshold levels are indicated with connecting lines (r, PCC). A relatively low threshold level (r > 0.5) was employed to detect weak relationships. B, Gene expression patterns of DP1 obtained from Bar eFP browser. C, Schematic representation of DP1 with the T-DNA insertion mutant used. The thick black line indicates coding sequence. The DP1 gene has no intron, and the gene region containing 5′-untranslated region and 3′-untranslated region is shown in the figure. Numbers indicate the position of the T-DNA insertion. LB, Left border; RB, right border. D, Selected ion chromatograms of seed extracts from the wild type (Columbia-0, bottom section) and the homozygous dp1 mutant (top section). The peak for 3-{4-[2-hydroxy-2-(4-hexosyloxy-3-methoxyphenyl)-1-hydroxymethylethoxy]-3,5-dimethoxyphenyl}acryloylcholine [SC(4-O-β)G 4′-O-hexoside] is shown.