Study of molecular mechanism for conidial dormancy in filamentous fungi

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K18672
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Applied microbiology
• Research Institution: University of Tsukuba (2017-2018); Chiba University (2016)
• Principal Investigator: Hagiwara Daisuke 筑波大学, 生命環境系, 准教授 (20612203)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 糸状菌胞子 / 休眠 / シグナル伝達 / トランスクリプトーム解析 / 二次代謝産物

Outline of Final Research Achievements

To understand which genes are involved in maintaining and exit for conidia dormancy, we conducted RNA-sequencing analysis for dormant conidia and 1h-germinated conidia in A. fumigatus, A. niger, and A. oryzae. From the transcriptome analysis, we identified the common conidia-associated genes (CAGs) and germinated conidia-associated genes (GeAGs). Expression of a large part of CAGs is dependent on bZip-type transcription factor AtfA. Furthermore, the conidia of atfA deletion mutant partly showed derepression of conidial dormancy. These results suggested that AtfA plays a crucial role in conidial dormancy. Our study also revealed that SakA MAPK in the HOG pathway which regulates function of AtfA was able to physically interact with protein kinase A (PKA). The PKA pathway has been reported to be involved in conidial germination. Therefore, the new working model for maintaining conidial dormancy is interaction between the HOG pathway and PKA pathway converged on AtfA.

Free Research Field

微生物学

Academic Significance and Societal Importance of the Research Achievements

糸状菌は環境中に遍在し、人間の社会生活の様々なところで関与する。一方で、胞子の休眠維持機構に関して、その分子基盤はほとんど明らかでなかった。本研究では、AtfAおよびその上流シグナリング経路について解析を進め、分子基盤としての関与について新しい知見を得ることができた。これらの解明により新たな抗菌剤や制御法などの開発に繋がることが期待される。