关键词: 基因组编辑, 高分辨率溶解曲线, OsBADH2, 水稻

Abstract: The fragrant quality of rice is an important agronomic trait concerned by consumers. Gene OsBADH2 in rice is the key one that affects the fragrant of rice,selecting high-quality elite rice varieties and conducting gene editing based on the gene is expected to create japonica rice materials with excellent fragrance. In this study,we analyzed the conservation of the exon sequence of OsBADH2 gene,selected three specific targets,and constructed the gRNA expression cassette driven by U6 promoter containing different targets and ligated into plant gene editing expression vector. Then,we used gene gun-mediated transient expression system to have genetic transformation of non-fragrant elite rice variety “Jijing 88” and obtained 847 regenerated materials of T₀. Finally we used high-resolution melting（HRM）to analyze and verify by sequencing,and there were different types of editing of OsBADH2 gene editing targets in 24 strains of T₀ generation materials. Seven T₁ lines were confirmed to be non-transgenic and homozygous in target sites. Our results showed that the resistance screening process was omitted in the process of transformation and regeneration based on the transient transformation system mediated by gene gun,and the gene-edited progenies with homozygous editing and non-transgenic components could be obtained in T₁ generation while supplemented by efficient HRM detection. The “Jijing 88” progenies via editing OsBADH2 gene also provides new materials for the cultivation of elite rice varieties with improved fragrance quality.

Key words: genome editing, high resolution melting, OsBADH2, Oryza sotiva ssp. japonica.