Analysis of the mechanism integrating light and circadian clock signals, which control rice flowering time

2018 Fiscal Year Final Research Report

• Project/Area Number: 17H07356
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Science in genetics and breeding
• Research Institution: National Agriculture and Food Research Organization
• Principal Investigator: Ogo Yuko 国立研究開発法人農業・食品産業技術総合研究機構, 次世代作物開発研究センター, 主任研究員 (90572214)
• Project Period (FY): 2017-08-25 – 2019-03-31
• Keywords: イネ / 出穂

Outline of Final Research Achievements

In rice, a short- day plant, floral transition in response to environmental conditions have been extensively studied. The molecular cascade Grain number, plant height, and heading date 7 (Ghd7)→Early heading date 1→Heading date 3a/Rice FT-like 1 and its interaction with Heading date 1 plays an important role for floral transition of rice. These genes are intricately regulated by light and circadian clocks.
In this study, we analyzed the transcriptional regulation of Ghd7 by light and circadian clocks. We produced the transformant rice for analysis of transcriptional regulation of Ghd7. Using these transformant rice, the expression pattern of Ghd7 and the downstream genes were analyzed in various day length conditions. The transformant rice with reporter genes after Ghd7 locus were produced by the efficient agrobacterium-mediated gene targeting system. ChIP-seq analysis was performed by transformant rice with the phytochrome-GFP protein.

Free Research Field

植物分子生物学

Academic Significance and Societal Importance of the Research Achievements

短日植物のイネの厳格な日長応答は、長日植物のシロイヌナズナとは異なるものであり、その制御機構について多くの研究がなされてきた。しかしながら、その中で重要な働きを示すGhd7について、発現制御機構の解析は進んでいなかった。本研究では、高効率遺伝子組換え法などの様々な新しい手法を用いて、Ghd7がどのように光と概日時計により制御されているのかを解析した。また、Ghd7は、開花期だけでなく植物体の生育にも大きな影響を与えることを再確認した。今後、どのようにGhd7が重要農業形質に関わっているのかを調べる予定であり、農業現場への応用にも重要であると考えられる。