Spatio-Temporal Regulation of Root Cap-specific Functions that Optimizes Root Growth

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H03248
• 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: Nara Institute of Science and Technology
• Principal Investigator: Nakajima Keiji 奈良先端科学技術大学院大学, 先端科学技術研究科, 教授 (80273853)
• Co-Investigator(Kenkyū-buntansha): 宮島 俊介 奈良先端科学技術大学院大学, 先端科学技術研究科, 助教 (20727169)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: 根冠 / 細胞剥離 / シロイヌナズナ / 根 / 周期性 / オルガネラ / 細胞分分化

Outline of Final Research Achievements

We conducted research to investigate the specific functions of the root cap and their underlying mechanisms in root growth. First, we constructed a microscope sysytem that can automatically track the tip of growing Arabidopsis roots. Using this microscope, we revealed that the root cap cells rapidly change their functions and subcellular structures according to their position in the tissue. We also found that autophagy is activated in the outermost root cap layer to reorganize their subcellular structures and the cell detachment process. We further revealed that the outer root cap cells express genes encoding enzymes for glucosinolate biosynthesis and their activation to produced antimicrobial substances, and thereby play an important role in the resistance of the entire root to pathogenic fungi.

Free Research Field

植物発生学

Academic Significance and Societal Importance of the Research Achievements

根冠は成長する根の最前線に位置する組織であり、根端の分裂組織を保護するほか、重力感受や代謝産物の分泌を介したミネラル吸収の促進、土壌微生物による病害への抵抗性など、植物の成長や生産力の維持に重要な役割を果たしている。根冠細胞の機能転換や細胞剥離を制御する仕組みの一端を解明した本研究成果は、植物の生産力の向上や土壌環境の改善につながる社会的意義を持つ。