Fine-tuning grain amylose contents by genome editing of Waxy cis-regulatory region in rice.

Zhang, Qi; Zhang, Sinan; Yu, Xiting; Wei, Xin; Huang, Xuehui; Zhou, Xiaoyi

Rice grain amylose contents (ACs) is a key quantitative trait influencing eating and cooking quality. Regulating the expression level of Waxy, a key gene controlling ACs, and in turn fine-tuning the grain ACs, is an ideal approach to improve grain quality of rice varieties. Based on CRISPR/Cas9 genome editing technology, we designed eight targets in the cis-regulatory region of Wxa background, screened phenotypic changes of the transgenic lines and generated eight novel Waxy alleles with altered grain ACs. Among the eight alleles, we found that a 407-bp non-homologous substitution (NHS) in the 5′UTR-intron caused by genome editing regulated Waxy expression and decreased grain ACs by 2.9%. Moreover, embedding the 407-bp NHS into the cis-regulatory region of Wxb allele can also affect gene activity. Our work suggested the effect of 5'UTR-intron on Waxy gene expression regulation, and provided a potentially useful allele in breeding that can finely adjust rice grain ACs.

GREAT Britain. National Health Service; RICE; GENETIC regulation; GENOME editing; AMYLOSE; GENE expression; RICE quality; PHENOTYPIC plasticity

Molecular Breeding, 2022, Vol 42, Issue 12, p1

1380-3743

Academic Journal

10.1007/s11032-022-01342-4