Development of transgenic rice containing a mutated β subunit of soybean β-conglycinin for enhanced phagocytosis-stimulating activity.

Improving the nutraceutical value of rice would positively impact the health and well-being of rice consumers worldwide. Based on the three-dimensional structure of soybean β-conglycinin, we designed a β subunit with a strong phagocytosis-stimulating activity (mβ subunit). Here, we describe the genetic modification and production of rice seeds containing the mβ subunit as part of our aim to develop a food material that promotes human health. The mβ subunit folded correctly and was accumulated in the protein body II of rice seeds at a level similar to wild-type β subunit. Mutant β subunit purified from transgenic rice seeds exhibited high phagocytosis-stimulating activity, demonstrating its potential value in enhancing the nutritional value of rice.