2026-02-13 理化学研究所,金沢大学,科学技術振興機構
高い膨圧により植物細胞に菌糸を侵入させる植物病原糸状菌のアプレッソリア
<関連情報>
- https://www.riken.jp/press/2026/20260213_2/index.html
- https://www.science.org/doi/10.1126/science.aec9443
ジヒドロキシヘキサン酸の生合成は病原性真菌の膨圧を制御する Dihydroxyhexanoic acid biosynthesis controls turgor in pathogenic fungi
Naoyoshi Kumakura, Takayuki Motoyama, Keisuke Miyazawa, Toshihiko Nogawa, […] , and Ken Shirasu
Science Published:12 Feb 2026
DOI:https://doi.org/10.1126/science.aec9443
Editor’s summary
Pathogenic fungi often penetrate plant cell walls using specialized fungal infection cells with high hydrostatic turgor pressure. Kumakura et al. identified two enzymes that are conserved across multiple fungal species and that biosynthesize a polymer called dihydroxyhexanoic acid (DHHA). DHHA reduces the porosity of fungal cell walls, making them only partially permeable, allowing the cell to build up higher turgor pressure. This contrasts with the role of melanin, which appears to increase cell wall strength. The DHHA-producing enzymes provide a potential target for antifungal measures, which may aid the protection of crops against disease. —Madeleine Seale
Abstract
Many plant pathogenic fungi penetrate host surfaces mechanically, using turgor pressure generated by specialized infection cells called appressoria. These appressoria develop semipermeable cell walls and accumulate osmolytes internally to create turgor by osmosis. Although melanin is known to be important for turgor generation, the mechanism underlying wall semipermeability remains unclear. By using reverse genetics, we identified that the enzymes PKS2 and PBG13 are required for forming the semipermeable barrier in fungi causing anthracnose and rice blast diseases. These enzymes synthesize 3,5-dihydroxyhexanoic acid polymers that are essential for pathogenicity. These polymers reduce cell wall permeability and generate turgor, independently of melanization. Our findings uncover a mechanism of fungal turgor generation, linking enzyme function to pathogen penetration and disease potential, presenting new targets for disease control.
