Development of vacuole palette for creating novel flower color

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K22301
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 39:Agricultural and environmental biology and related fields
• Research Institution: University of Tsukuba
• Principal Investigator: Ono Michiyuki 筑波大学, 生命環境系, 准教授 (50201405)
• Project Period (FY): 2019-06-28 – 2023-03-31
• Keywords: アサガオ / アントシアニン / 液胞 / 花色 / 形質転換植物 / シクラメン / ベタキサンチン / ベタレイン

Outline of Final Research Achievements

Making a new yellow flower is a dream of breeders, and we succeeded in yellowing morning glory flowers by introducing betaxanthin synthesis genes. Growth defects were observed in the transformed plants, but we identified the causes of these defects and devised a solution that can be adapted to many plant species. Only a limited number of plant species synthesize betacyanin in nature, and its synthesis system and flavonoid synthesis system are mutually exclusive. In this study, we demonstrated for the first time in the world that betaxanthin and flavonoids coexist in the same vacuole at the microscopic level, and analyzed the primary substances of both pigment syntheses. In addition, the whole genome sequence of cyclamen, which has longer-lived petals than morning glory, was decoded for the first time in the world with support by the Platform for Advanced Genome Science (PAGS) and many collaborators, and a stable experimental system for “the vacuolar palette" was established.

Free Research Field

植物バイオテクノロジー

Academic Significance and Societal Importance of the Research Achievements

アサガオなどの黄花化は育種家の夢であるが、ベタキサンチン合成系遺伝子の導入によりアサガオの黄花化に成功した。形質転換植物に生育障害が観察されたが、その原因を特定し、多くの植物種に適応できる解決策を考案した。自然界でベタシアニンを合成する植物種は限られており、その合成系とフラボノイド合成系は互いに排他的である。今回、ベタキサンチンとフラボノイドが同一の液胞内に共存することを顕微鏡レベルで世界で初めて示すと共に、両色素合成の初発物質を解析した。また、アサガオより長命な花弁を持つシクラメンの全ゲノム塩基配列を先進ゲノム支援により世界で初めて解読し「液胞のパレット化」のための安定した実験系を確立した。