Development of strigolactone function regulators and elucidation of strigolactne perception mechanisms

2014 Fiscal Year Final Research Report

• Project/Area Number: 23248018
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Bioproduction chemistry/Bioorganic chemistry
• Research Institution: The University of Tokyo
• Principal Investigator: ASAMI Tadao 東京大学, 農学生命科学研究科, 教授 (90231901)
• Project Period (FY): 2011-04-01 – 2015-03-31
• Keywords: 生理活性 / 植物 / 有機化学 / 農林水産物 / 遺伝子 / 受容体

Outline of Final Research Achievements

In plants, strigolactones (SLs) function as a phytohormone inhibiting shoot branching. An alpha/beta-hydrolase protein, DWARF14 (D14), and an F-box protein, DWARF3 (D3)/MAX2, have been shown to be involved in SL-signaling, although precise functions of them are largely unknown. Here we show the SL-dependent interaction of D14 with SLR1, a repressor of gibberellin signaling, the direct binding of SL to rice D14 (OsD14) protein, and the degradation of SL in vitro by D14. In addition, the X-ray crylstallographic analyses of OsD14 demonstrate the existence of open cavity sufficient for perceiving SLs, the binding of hydroxy D-ring, a putative product of SL hydrolysis by D14, to the cavity, and the amino acid residues critical for the interaction with the hydroxy D-ring. Our results present a novel model for the mechanism of SL recognition and signal transduction by D14. We found debranones as new chemicals possessing SL-like activity against the rice d10-1 mutant.

Free Research Field

農学