1. A Novel Soybean Diacylglycerol Acyltransferase 1b Variant with Three Amino Acid Substitutions Increases Seed Oil Content.
- Author
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Flyckt KS, Roesler K, Haug Collet K, Jaureguy L, Booth R, Thatcher SR, Everard JD, Ripp KG, Liu ZB, Shen B, and Wayne LL
- Subjects
- Saccharomyces cerevisiae genetics, Saccharomyces cerevisiae metabolism, Plant Proteins genetics, Plant Proteins metabolism, Soybean Oil metabolism, Soybean Oil genetics, Nicotiana genetics, Nicotiana enzymology, Glycine max genetics, Glycine max enzymology, Diacylglycerol O-Acyltransferase genetics, Diacylglycerol O-Acyltransferase metabolism, Seeds genetics, Seeds metabolism, Seeds enzymology, Amino Acid Substitution, Plants, Genetically Modified
- Abstract
Improving soybean (Glycine max) seed composition by increasing the protein and oil components will add significant value to the crop and enhance environmental sustainability. Diacylglycerol acyltransferase (DGAT) catalyzes the final rate-limiting step in triacylglycerol biosynthesis and has a major impact on seed oil accumulation. We previously identified a soybean DGAT1b variant modified with 14 amino acid substitutions (GmDGAT1b-MOD) that increases total oil content by 3 percentage points when overexpressed in soybean seeds. In the present study, additional GmDGAT1b variants were generated to further increase oil with a reduced number of substitutions. Variants with one to four amino acid substitutions were screened in the model systems Saccharomyces cerevisiae and transient Nicotiana benthamiana leaf. Promising GmDGAT1b variants resulting in high oil accumulation in the model systems were selected for overexpression in soybeans. One GmDGAT1b variant with three novel amino acid substitutions (GmDGAT1b-3aa) increased total soybean oil to levels near the previously discovered GmDGAT1b-MOD variant. In a multiple location field trial, GmDGAT1b-3aa transgenic events had significantly increased oil and protein by up to 2.3 and 0.6 percentage points, respectively. The modeling of the GmDGAT1b-3aa protein structure provided insights into the potential function of the three substitutions. These findings will guide efforts to improve soybean oil content and overall seed composition by CRISPR editing., (© The Author(s) 2023. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists.)
- Published
- 2024
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