Overexpressed Sweet Potato Gene Results in Higher Arabidopsis Seed Yield

Expansins are proteins that mediate cell-wall loosening and are regulators of wall extension during plant cell growth. However, limited information is available on their precise biological functions in plant growth and development. Previous transcriptome analyses suggest that expansin genes play an active role in seed development and yield. In this study, a sweet potato expansin gene (IbEXP1) was overexpressed in Arabidopsis to determine the effect of the expansin gene in seed development and yield in heterologous plants.

The growth rate was enhanced in IbEXP1-overexpressing plants relative to wild-type plants during early vegetative growth stage. More rosette leaves and thicker siliques were observed in transgenic plants than in control during reproductive stage. Transgenic plants also produced larger seeds and accumulated more protein and starch in seeds. Transgenics also produced more inflorescence stems and siliques than wild-type plants, leading to higher total seed yield per plant.

The results showed the favorable effect of the overexpression of IbEXP1 gene on seed size and seed number in heterologous plants. The improvement of these two phenotypes directly leads to a better seed yield.

For more information on this study, please visit http://link.springer.com/article/10.1007/s11248-014-9804-1/fulltext.html.