Investigating the Symbiotic Mechanisms of Ectomycorrhizal Fungus Lyophyllum shimeji Using Gene Disruption Techniques

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K06148
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 40010:Forest science-related
• Research Institution: The University of Shiga Prefecture
• Principal Investigator: Izumitsu Kosuke 滋賀県立大学, 環境科学部, 准教授 (20579263)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 外生菌根菌 / ホンシメジ / GH115

Outline of Final Research Achievements

Through a large-scale genome comparison method between ectomycorrhizal fungi and decay fungi (such as white rot fungi and brown rot fungi), we identified numerous genes that have been evolutionarily lost in ectomycorrhizal fungi. Among them, the GH115 (Glycosyl hydrolase 115) gene, which is involved in hemicellulose degradation, showed the most significant difference. We created a strain of the ectomycorrhizal fungus Honshimeji (Lyophyllum shimeji) that expresses this gene heterologously. Additionally, we succeeded in visualizing the fungal hyphae by creating L. shimeji that expresses the mCherry gene, a fluorescent protein. Using these strains, we are advancing symbiosis tests with the host plant Japanese red pine (Pinus densiflora).

Free Research Field

菌類分子遺伝学

Academic Significance and Societal Importance of the Research Achievements

外生菌根菌は森林生態系を支える非常に重要な微生物群である。しかし、外生菌根共生の分子メカニズムや分子進化機構についてはほとんどわかっていない。外生菌根菌と腐朽菌の大規模ゲノム比較試験の結果や作成した遺伝子組換え株は、これらを解明していくための一助となるはずである。さらに、マツタケやトリュフなどの難栽培きのこのほとんどは外生菌根菌であり、共生メカニズムおよび腐朽メカニズムを解明することは人工栽培への基礎的な知見となるものと考えられる。