- 著者
- Kana Takehara Kazumasa Murata Takuya Yamaguchi Kohei Yamaguchi Genki Chaya Shintaro Kido Yukimoto Iwasaki Hitoshi Ogiwara Takeshi Ebitani Kotaro Miura
- 出版者
- Japanese Society of Breeding
- 雑誌
- Breeding Science (ISSN:13447610)
- 巻号頁・発行日
- pp.18007, (Released:2018-06-23)
- 被引用文献数
- 25
High-temperature stress during the ripening stage leads to quality deterioration due to an increase in chalky grains in brown rice (Oryza sativa L.). In a previous study, we identified a QTL for Appearance quality of brown rice 1 (Apq1) using chromosome segment substitution lines of the indica cultivar ‘Habataki’ in the japonica cultivar ‘Koshihikari’ background and narrowed down the locus to a 48-kb region on chromosome 7. To verify the function and mechanisms of this QTL in grain appearance, in this study, we fine-mapped the gene and conducted high-temperature tolerance tests. As a result of the genetic mapping, we narrowed down the candidate region of Apq1 to a 19.4-kb region including three predicted genes. Among these, the temporal expression pattern of sucrose synthase 3 (Sus3) corresponded well with the high temperature-sensitive period during ripening, and expression of the ‘Habataki’ allele of Sus3 was increased under high-temperature condition. In addition, we transformed the ‘Habataki’ Sus3 gene into ‘Nipponbare’, and the transformants obtained high-temperature tolerance. Therefore, we conclude that the causal gene underlying the QTL Apq1 is the thermo-responsive Sus3 allele, and the increase in Sus3 expression under high-temperature condition during ripening leads to high-temperature tolerance in rice.