Identification and characterization of Dominant Awn Inhibitor gene in sorghum

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K05570
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39010:Science in plant genetics and breeding-related
• Research Institution: The University of Tokyo
• Principal Investigator: Takanashi Hideki 東京大学, 大学院農学生命科学研究科(農学部), 助教 (60707149)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: ソルガム / 芒 / 器官分化

Outline of Final Research Achievements

There has been little progress in the study of awn in sorghum, and none of the genes involved in awn length have been reported. I conducted a QTL analysis for awn length in the sorghum RIL population and found a QTL that suppressed awn formation in an oddly dominant manner. I found SbDAI (Dominant Awn Inhibitor) as a candidate causable gene for this QTL, and succeeded in proving that the awn formation was inhibited by introducing SbDAI gene to an awned sorghum line. In addition, RNA-seq analysis using NILs for SbDAI successfully identified a group of genes whose expression varied depending on the presence or absence of DAI.

Free Research Field

植物分子遺伝学

Academic Significance and Societal Importance of the Research Achievements

芒はイネ科植物小穂の護穎の先端から伸びる針状の突起構造で, イネ科野生種は基本的に有芒 (有芒が優性形質) であり, また芒は人類が栽培化の過程で除去を試みてきた「栽培化の歴史」を紐解くうえでも非常に重要な形質でもある.
これまで芒長を優性で伸長させるタイプの遺伝子が多数同定されてきたイネやオオムギと異なり, 本研究で同定されたソルガムのSbDAIは優性で芒を消失させるという珍しいタイプの遺伝子であった. 興味深い優性芒抑制遺伝子が同定されたことは, 今後の応用利用のみならず, 遺伝子の進化についても様々な示唆を与える興味深い結果であると言える.