Expression of the high molecular weight glutenin 1Ay gene from Triticum urartu in barley

https://link.springer.com/article/10.1007/s11248-019-00117-6

Qiang Yang, Siyu Li, Xiaoyu Li, Jian Ma, Jirui Wang, Pengfei Qi, Guoyue Chen, Zhien Pu, Wei Li, Wendy Harwood, Zhongyi Li, Bao-Long Liu, Xiujin Lan, Mei Deng, Zhenxiang Lu, Yuming Wei, Youliang Zheng, Qiantao Jiang

Abstract

In this study, we successfully expressed the active 1Ay subunit of Triticum urartu in barley by Agrobacterium-mediated transformation with a transformation efficiency of 19.9%. The results of SDS–PAGE revealed that the expressed proteins of 1Ay subunit were present at some grains of each of 46 original T0 plants, showing identical mobility to those of positive standards of T. urartu grain protein and bacteria expressional proteins. In the T2 generation, three homozygous lines, 2–28, 3–11, and 5–6, were identified. The results of scanning electron microscopy showed an increased amount of protein bodies in these transgenic lines. The main effects in the expression of the 1Ay subunits was a considerable increase in the glutenin content, but a decrease in the contents of gliadins while there were no effects in the contents of albumin, globulin and the total protein. We found that the gluten could not be washed out from the flour obtained from transgenic barley lines when using a Gluten index analyzer and a Farinograph indicating that the transgenic barley lines could not form dough. The lack of x-type HMW-GS and the reduction in number of subunit were inferred as the possible reasons for the inability to form gluten polymer.

Keywords

Agrobacterium transformation, High-molecular-weight glutenin subunit, Hordeum vulgare, Copy numbers, Protein contents, Gluten quality