Development of Marker-free Transgenic Rice Expressing the Wheat Storage Protein, Glu-1Dy10, for Increasing Quality Processing of Bread and Noodles

Abstract

Rice flour is used in many food products. However, dough made from rice lacks extensibility and elasticity, making it less suitable than wheat for many food products such as bread and noodles. The high-molecular weight glutenin subunits (HMW-GS) of wheat play a crucial role in determining the processing properties of the wheat grain. This paper describes the development of marker-free transgenic rice plants expressing a wheat Glu-Dy10 gene encoding the HMG-GS from the Korean wheat cultivar 'Jokyeong' using Agrobacterium-mediated co-transformation. Two expression cassettes, consisting of separate DNA fragments containing Glu-1Dy10 and hygromycin phosphotransferase II (HPTII) resistance genes, were introduced separately into Agrobacterium tumefaciens EHA105 for co-infection. Each EHA105 strain harboring Glu-1Dy10 or HPTII was infected into rice calli at a 3: 1 ratio of Glu-1Bx7 and HPTII. Among 290 hygromycin-resistant T0 plants, we obtained 29 transgenic lines with both the Glu-1Dy10 and HPTII genes inserted into the rice genome. We reconfirmed the integration of the Glu-1Dy10 gene into the rice genome by Southern blot analysis. Transcripts and proteins of the Glu-1Dy10 in transgenic rice seeds were examined by semi-quantitative RT-PCR and Western blot analysis. The marker-free plants containing only the Glu-1Dy10 gene were successfully screened in the T1 generation.

Molecular characterization and expression of α-gliadin genes from wheat cultivar Dacke in Bg 250 rice variety

“…15 In the past years, glutenin genes (LMW &HMW) have been successfully expressed in E. coli 16 as well as transferred to different wheat [17][18][19][20] and rice cultivars. [21][22][23][24][25][26] Gliadin has been expressed in E. coli. 27 However, reports on the transgenic expression of gliadin in plants are limited.…”

Overexpressing wheat low-molecular-weight glutenin subunits in rice (Oryza sativa L. japonica cv. Koami) seeds

“…Moreover, the bread-making qualities of rice were improved by adding wheat gluten to rice dough (Sivaramakrishnan et al 2004;Shin 2009). In addition, many molecular breeding studies have been undertaken to improve the bread-making qualities of rice through genetic engineering, including the production of soybean β-conglycinin subunits in rice seeds to improve nutritional and processing properties (Motoyama et al 2009) and the expression of wheat HMW-GSs such as 1Ax1, 1Bx7, 1Dx5, and 1Dy10 in rice seeds to improve dough-making qualities (Jeong et al 2016;Park et al 2014;Oszvald et al 2007Oszvald et al , 2013Jo et al 2017). However, improving the poor suitability of rice flour for various food products remains an important challenge in countries where rice is used as a staple crop.…”

Cellular Localization of Wheat High Molecular Weight Glutenin Subunits in Transgenic Rice Grain

“…In addition, the over-expression of wheat 1Dx5 and/or 1Dy10 HMW-GSs improves the extensibility and elasticity of dough from wheat [ 26 , 27 , 28 ] and rye [ 29 ]. In efforts that were aimed at improving rice dough quality, preliminary attempts have been made to express wheat SSPs, including 1Ax1 [ 30 ], 1Bx7 [ 31 ], 1Dx5 [ 32 , 33 ], and 1Dy10 [ 34 ] in rice seeds, although to date, only 1Dx5 has been shown to confer a positive effect on rice dough properties. The objective of this study was to engineer wheat HMW-GS into rice seeds.…”