Figure 1.

The seeds of an Arabidopsis thaliana double mutant, hise1-3 psat1-2, exhibit deeper color and higher contents of proanthocyanidins than those of the wild type. (a) Photographs of dry seeds of the wild type, hise1-3, psat1-2, and hise1-3 psat1-2. (b, c) Average values of the major axis (b) and minor axis (c) of 15 seed grains of each genotype. Data represent the mean ± standard deviation (SD; n = 15). Different letters indicate significant differences (p < .05; Tukey’s test). (d) Average dry weight of one seed grain. To measure seed weight, 150 seeds were collected and weighed with an electronic balance. The weight of one seed was calculated. Three biological replicates were performed. Data represent the mean ± SD (n = 3). Different letters indicate significant differences (p < .05; Tukey’s test). (e) Relative contents of acetone-soluble (soluble), acetone-insoluble (insoluble), and total proanthocyanidins in wild-type and hise1-3 psat1-2 seeds in three biological replicates. Data represent the mean ± SD (n = 3). Asterisks indicate significant differences between wild-type and hise1-3 psat1-2 seeds (p < .05; two-tailed Student’s t-test). The relative total proanthocyanidin content was calculated as follows: acetone-soluble proanthocyanidin content plus acetone-insoluble proanthocyanidin content was defined as total proanthocyanidin content. The relative total proanthocyanidin content of wild-type seeds was set at 1.0. (f) Relative content of sterols in wild-type, hise1-3, psat1-2, and hise1-3 psat1-2 dry seeds. The sterol content of total lipid extracts from seeds was measured with a Cholesterol Quantitation Kit (Sigma-Aldrich). In this experiment, cholesterol esterase treatment was not performed. The relative content of sterols of wild-type seeds was set at 1.0. Three biological replicates were performed. Data represent the mean ± SD (n = 3). Different letters indicate significant differences (p < .05; Tukey’s test)