著者

Kumi YOSHIDA Naoko MIKI Kazumi MOMONOI Miki KAWACHI Kiyoshi KATOU Yoshiji OKAZAKI Nobuyuki UOZUMI Masayoshi MAESHIMA Tadao KONDO

出版者

The Japan Academy

雑誌

Proceedings of the Japan Academy, Series B (ISSN:03862208)

巻号頁・発行日

vol.85, no.6, pp.187-197, 2009 (Released:2009-06-12)

参考文献数

42

被引用文献数

27 45

---

Petal color change in morning glory Ipomoea tricolor cv. Heavenly Blue, from red to blue, during the flower-opening period is due to an unusual increase in vacuolar pH (pHv) from 6.6 to 7.7 in colored epidermal cells. We clarified that this pHv increase is involved in tonoplast-localized Na+/H+ exchanger (NHX). However, the mechanism of pHv increase and the physiological role of NHX1 in petal cells have remained obscure. In this study, synchrony of petal-color change from red to blue, pHv increase, K+ accumulation, and cell expansion growth during flower-opening period were examined with special reference to ItNHX1. We concluded that ItNHX1 exchanges K+, but not Na+, with H+ to accumulate an ionic osmoticum in the vacuole, which is then followed by cell expansion growth. This function may lead to full opening of petals with a characteristic blue color.(Communicated by Ryoji NOYORI, M.J.A.)

著者

Kumi YOSHIDA Kin-ichi OYAMA Tadao KONDO

出版者

The Japan Academy

雑誌

Proceedings of the Japan Academy, Series B (ISSN:03862208)

巻号頁・発行日

vol.97, no.2, pp.51-68, 2021-02-10 (Released:2021-02-10)

参考文献数

63

被引用文献数

5

---

Hydrangea (Hydrangea macrophylla) is a unique flower because it is composed of sepals rather than true petals that have the ability to change color. In the early 20th century, it was known that soil acidity and Al3+ content could intensify the blue hue of the sepals. In the mid-20th century, the anthocyanin component 3-O-glucosyldelphinidin (1) and the copigment components 5-O-caffeoylquinic, 5-O-p-coumaroylquinic, and 3-O-caffeoylquinic acids (2–4) were reported. Interestingly, all hydrangea colors from red to purple to blue are produced by the same organic components. We were interested in this phenomenon and the chemical mechanisms underlying hydrangea color variation. In this review, we summarize our recent studies on the chemical mechanisms underlying hydrangea sepal color development, including the structure of the blue complex, transporters involved in accumulation of aluminum ion (Al3+), and distribution of the blue complex and aluminum ions in living sepal tissue.

著者

Natsu TANIKAWA Kumi YOSHIDA Tadao KONDO Takayuki MIZUNO Tsukasa IWASHINA Masayoshi NAKAYAMA

出版者

Japan Society for Bioscience, Biotechnology, and Agrochemistry

雑誌

Bioscience, Biotechnology, and Biochemistry (ISSN:09168451)

巻号頁・発行日

pp.1109052652, (Released:2011-10-07)

参考文献数

8

被引用文献数

5

---

A new tetraglycosyl flavonol, 3-O-[2-O-xylosyl-6-O-(3-O-glucosyl-rhamnosyl) glucosyl] kaempferol was isolated from pale purplish-pink petals of Wabisuke camellia cv. Tarokaja with three known flavonols. It was named urakunoside after the species name of Tarokaja, Camellia uraku. Urakunoside was a major flavonol component in the Tarokaja petals, but was not detected in petals of Tarokaja’s presumed ancestor species.