Seed oil is important for human and animal nutrition as well as for various industrial applications. Genetic engineering strategies have been tried to increase oil content in seeds. However, few of these strategies involve manipulating the transporters. Pyruvate is a major source of carbon for fatty acid biosynthesis in plastids, and the embryo's demand for it is reported to increase during oil accumulation. The team of Eun-Jung Lee of  Pohang University of Science and Technology in South Korea aimed to boost oil biosynthesis by increasing pyruvate flow into plastids.

The team expressed the plastid-localized pyruvate transporter BILE ACID:SODIUM SYMPORTER FAMILY PROTEIN 2 (BASS2) in Arabidopsis thaliana. The resulting transgenic Arabidopsis plants overexpressing BASS2, produced seeds that were larger and heavier. The transgenic seeds also contained 10-37% more oil than wild types despite having comparable protein and carbohydrate contents. This reflected to an increase of 24-43% in oil yield per plant.

These data demonstrate that seed-specific overexpression of the pyruvate transporter BASS2 can enhance oil production in Arabidopsis seeds. Furthermore, it also proves that manipulating specific transporters is a feasible approach for increasing the seed oil content.

For more on this study, read the article in Frontiers in Plant Science.