Constitutive expression of the GIGANTEA Ortholog Affects Circadian Rhythms and Suppresses One-shot Induction of Flowering in Pharbitis nil, a Typical Short-day Plant

被引：25

作者：

Higuchi, Yohei ^{[1
]}

Sage-Ono, Kimiyo ^{[1
]}

Sasaki, Ryuta ^{[1
]}

Ohtsuki, Namie ^{[1
]}

Hoshino, Atsushi ^{[2
]}

Iida, Shigeru ^{[2
]}

Kamada, Hiroshi ^{[1
]}

Ono, Michiyuki ^{[1
]}

机构：

[1] Univ Tsukuba, Grad Sch Life & Environm Sci, Tsukuba, Ibaraki 3058572, Japan

[2] Natl Inst Basic Biol, Okazaki, Aichi 4448585, Japan

来源：

PLANT AND CELL PHYSIOLOGY | 2011年 / 52卷 / 04期

关键词：

Circadian rhythm; Flowering; GIGANTEA; Pharbitis nil; Photoperiodism; Short-day plant; CLOCK-RELATED GENES; PHOTOPERIODIC CONTROL; MESSENGER-RNA; RESPONSE REGULATOR; NUCLEAR-PROTEIN; MOLECULAR-BASIS; DISTINCT ROLES; DAY-LENGTH; ARABIDOPSIS; LIGHT;

D O I：

10.1093/pcp/pcr023

中图分类号：

Q94 [植物学];

学科分类号：

071001 ;

摘要：

GIGANTEA (GI) is a key regulator of flowering time, which is closely related to the circadian clock function in Arabidopsis. Mutations in the GI gene cause photoperiod-insensitive flowering and altered circadian rhythms. We isolated the GI ortholog PnGI from Pharbitis (Ipomoea) nil, an absolute short-day (SD) plant. PnGI mRNA expression showed diurnal rhythms that peaked at dusk under SD and long-day (LD) conditions, and also showed robust circadian rhythms under continuous dark (DD) and continuous light (LL) conditions. Short irradiation with red light during the flower-inductive dark period did not change PnGI expression levels, suggesting that such a night break does not abolish flowering by affecting the expression of PnGI. In Pharbitis, although a single dusk signal is sufficient to induce expression of the ortholog of FLOWERING LOCUS T (PnFT1), PnGI mRNA expression was not reset by single lights-off signals. Constitutive expression of PnGI (PnGI-OX) in transgenic plants altered period length in leaf-movement rhythms under LL and affected circadian rhythms of PnFT mRNA expression under DD. PnGI-OX plants formed fewer flower buds than the wild type when one-shot darkness was given. In PnGI-OX plants, expression of PnFT1 was down-regulated, suggesting that PnGI functions as a suppressor of flowering, possibly in part through down-regulation of PnFT1.

引用

页码：638 / 650

页数：13