Rice protein yields hope for increased food supply

31 December 2019

Rice provides daily subsistence for about three billion people worldwide and its output must keep pace with the growing global population. Thus, the identification of genes that enhance grain yield and composition is a sought-after quest.

Research led by Professor Chye Mee-Len (Croucher Senior Research Fellowship 2007), School of Biological Sciences, University of Hong Kong (HKU), in collaboration with researchers from the University of Calgary, Canada, and Rothamsted Research, UK, has now found a way to enhance grain yield in rice by increasing grain size and weight.

The research has been published in The Plant Journal and an international patent filed.

The researchers identified a protein, ACYL-COA-BINDING PROTEIN2 (OsACBP2), from rice that when overexpressed in transgenic rice enhanced grain size, weight and biomass by 10 per cent.

They also found that the protein increased the lipid content of rice bran and whole seeds, raising the nutritional value of the modified rice by 10 per cent. OsACBP2 is a lipid-binding protein that binds lipids such as acyl-CoA esters, the major precursors in seed oil production. Oil therefore accumulates in the transgenic rice grains.

Since the protein can boost oil content as well as size and weight in transgenic rice grains, the technology is expected to benefit agriculture by increasing grain yield and composition to satisfy the need for more food.

Chye said: “Rice bran oil is considered highly valuable because it contains bioactive components that have been reported to lower serum cholesterol and possess anti-oxidation, anti-carcinogenic and anti-allergic inflammation activities.

“This technology, if applied to other food crops, would not only help address food security but also elevate nutritional properties in grains.”

Professor Chye Mee-Len, Wilson and Amelia Wong Professor in Plant Biotechnology, at the University of Hong Kong (HKU), completed her PhD on a Commonwealth Scholarship at the University of Melbourne and received postdoctoral training in plant molecular biology at The Rockefeller University, New York, and the Institute of Molecular and Cell Biology, Singapore. She joined HKU in 1993 and was promoted to Professor in 2005. Other roles have included Associate Dean (April 2010-April 2016) and Dean (May 2016-August 2019) of the Graduate School. She received a Croucher Senior Research Fellowship in 2007.

To view Professor Chye’s Croucher profile, please click here.