Functional roles of lectins in disease resistance in tomato.

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K06057
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 39040:Plant protection science-related
• Research Institution: Tokyo University of Agriculture
• Principal Investigator: Oguri Suguru 東京農業大学, 生物産業学部, 教授 (70277250)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: レクチン / キチン / Botrytis cinerea / トマト

Outline of Final Research Achievements

Tomato is known to produce chitin-binding lectin in ripe fruits, which has been used for analyzing sugar chain structures. However, the physiological roles of the lectin remained unknown. We have identified the secund lectin gene expressed in the leaves, and designated it as TL-L, distinguishing it from the authentic lectin (TL-F) expressed in fruits. The expression of the TL-L gene was induced in leaflets by wound treatment of tomato plants. These observations suggested that TL-L is involved in plant defense. We analyzed the distribution of both lectin genes among inbred tomato cultivars and found that tomatoes possess either of the two lectin genes. Both genes behaved as alleles in crossing experiments with homozygote of each lectin gene. Reduction of TL-L expression by RNA interference resulted in reduced resistance to B. cinerea infection. These observations are expected to contribute to a better understanding of disease resistance in tomato.

Free Research Field

糖鎖生物学

Academic Significance and Societal Importance of the Research Achievements

トマト果実レクチン（TL-F）は、糖鎖構造解析に広く利用されてきたが、その生物学的役割は不明であった。本研究において我々は、トマト小葉において発現する第二のレクチン遺伝子TL-Lがトマトの病害抵抗性に寄与していることをTL-L遺伝子の発現抑制体を用いた解析から示した。TL-LとTL-Fは対立遺伝子の関係にあり、トマト固定品種はどちらか一方の遺伝子のみを保有するという本研究の結果は、TL-L遺伝子の保持を糸状菌抵抗性の育種選抜に際して利用可能であることを示している。今後は、TL-Lの作用機序の解明を通して感染過程における宿主と病原菌との相互作用について新たな知見が得られることを期待する。