Figure 4.

Role of MYB118.

(A) Molecular characterization of myb118-1 and OE3 lines. Structure of the MYB118 gene showing the position of the T-DNA insertion in myb118-1 is presented. Confirmed flanking sequence tag is anchored in the gene structure and represented by a vertical bar. Closed boxes represent exons and open boxes untranslated regions (UTR). Accumulation of MYB118 mRNA in wild-type and transgenic backgrounds was studied by RT-PCR on developing seeds harvested 10 DAA. EF1αA4 (EF) gene expression was used as a constitutive control. Primers used for this study are indicated as arrows (Supplemental Table 4).

(B) Total fatty acid content of endosperm and embryo fractions dissected from wild-type or myb118-1 seeds during early (12 DAA) or late maturation (20 DAA). Values are the means and se of five replicates performed on batches of 20 individuals from five distinct plants. ***Significant difference according to t test, P < 0.001.

(C) Total fatty acid content of endosperm fractions dissected from wild-type, mutant, or complemented mature dry seeds. Values are the means and se of five replicates performed on batches of 20 individuals from five distinct plants.

(D) Storage protein content in embryo and endosperm fractions of wild-type and mutant dry seeds. A representative gel stained with Coomassie Blue G 250 is presented. Each lane contains an amount of proteins equivalent to 16 (endosperm fraction) or to four individuals (embryo fraction).

(E) Immunoblots of embryo and endosperm fractions using primary antibodies raised against 12S cruciferins (anti-12S serum) or 2S napins (anti-2S serum) and anti-rabbit secondary antibodies conjugated with horseradish peroxidase are presented. Relative protein contents (in arbitrary units [AU]) among genotypes and for a given fraction were then analyzed with the MultiGauge software. The amount of protein loaded in each lane of the gels corresponding to embryo fractions was equivalent to 0.05 embryo. The amount of protein loaded in each lane of the gels corresponding to endosperm fractions was 0.2 endosperm equivalents.

Emb., embryo fraction; Endo., endosperm fraction; WT, the wild type (Col-0).

[See online article for color version of this figure.]