Creation and gene expression analysis of a giant embryo rice mutant with high GABA content

Pingli Chen; Qing Liu; Bingrui Sun; Shuwei Lv; Liqun Jiang; Jing Zhang; Xingxue Mao; Hang Yu; Yangyang Chen; Wenfeng Chen; Zhilan Fan; Dajian Pan; Chen Li

doi:10.1007/s11032-022-01353-1

Creation and gene expression analysis of a giant embryo rice mutant with high GABA content

Mol Breed. 2023 Jan 11;43(1):3. doi: 10.1007/s11032-022-01353-1. eCollection 2023 Jan.

Authors

Pingli Chen¹, Qing Liu¹, Bingrui Sun¹, Shuwei Lv¹, Liqun Jiang¹, Jing Zhang¹, Xingxue Mao¹, Hang Yu¹, Yangyang Chen¹, Wenfeng Chen¹, Zhilan Fan¹, Dajian Pan¹, Chen Li¹

Affiliation

¹ Rice Research Institute, Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of New Technology in Rice Breeding/Guangdong Rice Engineering Laboratory/Key Laboratory of Genetics and Breeding of High Quality Rice in Southern China (Co-Construction By Ministry and Province), Ministry of Agriculture and Rural Affairs, Guangzhou, 510640 China.

Abstract

Gamma-amino butyric acid (GABA) is a natural non-protein amino acid involved in stress, signal transmission, carbon and nitrogen balance, and other physiological processes in plants. In the human body, GABA has the effects of lowering blood pressure, anti-aging, and activating the liver and kidneys. However, there are few studies on the molecular regulation mechanism of genes in the metabolic pathways of GABA during grain development of giant embryo rice with high GABA content. In this study, three glant embryo (ge) mutants of different embryo sizes were obtained by CRISPR/Cas9 knockout, and it was found that GABA, protein, crude fat, and various mineral contents of the ge mutants were significantly increased. RNA-seq and qRT-PCR analysis showed that in the GABA shunt and polyamine degradation pathways, the expression levels of most of the genes encoding enzymes promoting GABA accumulation were significantly upregulated in the ge-1 mutant, whereas, the expression levels of most of the genes encoding enzymes involved GABA degradation were significantly downregulated in the ge-1 mutant. This is most likely responsible for the significant increase in GABA content of the ge mutant. These results help reveal the molecular regulatory network of GABA metabolism in giant embryo rice and provide a theoretical basis for the study of its development mechanisms, which is conducive to the rapid cultivation of GABA-rich rice varieties, promoting human nutrition, and ensuring health.

Supplementary information: The online version contains supplementary material available at 10.1007/s11032-022-01353-1.

Keywords: CRISPR/Cas9; Gamma-amino butyric acid (GABA); Giant embryo rice; Grain development; RNA-seq.

© The Author(s), under exclusive licence to Springer Nature B.V. 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.