Functional analysis of MYB transcription factors involved in root hair formation

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K07644
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Plant nutrition/Soil science
• Research Institution: Hiroshima University
• Principal Investigator: Tominaga Rumi 広島大学, 生物圏科学研究科, 准教授 (20373334)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: シロイヌナズナ / 根毛 / 転写因子

Outline of Final Research Achievements

The Arabidopsis root hair cell fate is decided by an R3-type MYB transcription factor, CPC. CPC has additional homologs, including TRY, ETC1, ETC2, and CPL3. The transgenic plants expressing CPC, ETC1, and CPL3 showed a significant increase in the number of root hairs. In contrast, TRY and ETC2 transgenic plants did not show any obvious induction of additional root hairs. TRY and ETC2 have an extended C-terminal region. Therefore, we deleted the C-termini of TRY and ETC2, respectively, and observed that these deletions resulted in TRY and ETC2 having functions similar to those of CPC, ETC1, and CPL3. We also demonstrated that the substitution of amino acids in the C-terminal of TRY and ETC2 conferred them the ability to induce root hair formation. Furthermore, we confirmed that these mutations enhanced the stability of the TRY and ETC2 proteins.

Free Research Field

植物分子生物学

Academic Significance and Societal Importance of the Research Achievements

モデル植物であるシロイヌナズナの表皮細胞に着目した細胞分化の研究により、植物細胞の形態形成制御機構の理解に大きく貢献できる。植物に特異的なR3 MYB転写因子の解析により、MYBを中心とした転写因子複合体の制御メカニズムの一端を明らかにできた。根毛形成を制御することで、水分や養分の不足しがちな過酷な環境で生育できる作物育種への応用が期待できる。トライコームは、病害虫から植物体を守る器官であると同時に、種によっては、二次代謝産物を蓄積する器官である。将来的には、植物の産生する有用物質の利用を含む応用展開が期待できる。