Elucidation of signal transduction pathways that regulate the biosynthesis of a plant immune hormone salicylic acid

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H03274
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 44030:Plant molecular biology and physiology-related
• Research Institution: Nagoya University
• Principal Investigator: Tada Yasuomi 名古屋大学, 遺伝子実験施設, 教授 (40552740)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: サリチル酸 / 植物免疫 / 疾病防除 / 生物的ストレス / 非生物的ストレス

Outline of Final Research Achievements

We selected cis-elements that are enriched on the promoters of 327 genes that are commonly expressed in response to various stresses such as pathogenic bacteria, ozone, and UV. Then, we identified three transcription factors (SBR1, 2, and 3) that recognize these cis-elements. We confirmed that SBRs induce the expression of SA synthesis-related genes ICS1 and PBS3. We generated dexamethasone (DEX)-inducible SBR plants (pDEX:SBR-GFP) and confirmed that the expression of the transcription factors CBP60g and SARD1, responsible for SA synthesis as well as ICS1 and PBS3. SA was significantly accumulated in leaves treated with DEX. RNA-seq analysis demonstrated that SBRs induce the expression of defense-related genes and SA synthesis-related genes. In addition, ChIP-seq analysis showed that SBR is distributed on the promoters of SA synthesis-related genes.

Free Research Field

植物病理

Academic Significance and Societal Importance of the Research Achievements

病原菌、オゾンやUVなど多様なストレスを感知し、サリチル酸の合成を開始する転写因子SBRを同定した。SBRは生物的あるいは非生物的ストレス応答に重要な役割を担っていると考えられ、ストレス応答の中枢因子であると言える。これまで、各ストレスからサリチル酸合成に至る情報伝達経路は未解明であったため、個別の情報伝達経路の理解にも多大な貢献をなすと考えられる。一因子が多くのストレスに対して耐性を付与できることから、分子育種上の重要因子として捉えることができる。