Physiological and ecological functions of beta-tyrosine produced by Oryza sativa

2020 Fiscal Year Final Research Report

• Project/Area Number: 17K07770
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Bioorganic chemistry
• Research Institution: Kyoto University
• Principal Investigator: Mori Naoki 京都大学, 農学研究科, 教授 (30293913)
• Co-Investigator(Kenkyū-buntansha): 寺石 政義 京都大学, 農学研究科, 准教授 (80378819)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 非天然アミノ酸 / 根の伸長阻害 / アレロパシー活性 / beta-tyrosine

Outline of Final Research Achievements

(1) (3R)- and (3S)-β-tyrosine showed inhibitory activity on Arabidopsis root elongation, whereas neither m-(3R)-β-tyrosine nor o-(3R)-β-tyrosine showed any inhibitory activity. The coexistence of an amino group at the β-position and a hydroxy group at the p-position in the benzene ring was required for the activity. (2) The accumulation of (R)-β-tyrosine in rice plants at different growth stages (3rd, 5th and 7th leaf stage) showed that (3R)-β-tyrosine accumulated after the 5th leaf stage. The highest accumulation of (3R)-β-tyrosine was observed in the fifth leaf of the fully expanded rice plants. The diurnal variation of (3R)-β-tyrosine accumulation in the fully expanded fifth leaf of rice was constant, unlike that of other amino acids. This result indicates that the dynamics of (3R)-β-tyrosine accumulation is different from those of other amino acids.

Free Research Field

化学生態学

Academic Significance and Societal Importance of the Research Achievements

日本晴（イネ、ジャポニカ種）は非タンパク性アミノ酸(3R)-β-tyrosineを産生する．(3R)-β-Tyrosinは双子葉植物の根の伸長を特異的に阻害するが，イネ等の単子葉類には活性を示さない．(3R)-β-tyrosineおよびその類縁体を用いて構造と活性を比較したところ，活性発現にはβ-位のアミノ基とベンゼン環中のp-位の水酸基の共存が必要であった．イネには無害で，双子葉雑草に効果を示す薬剤のシーズ開発につながる成果を得た．