The Arabidopsis RING Domain Protein BOI Inhibits Flowering via CO-dependent and CO-independent Mechanisms

Nguyen, Khoa Thi; Park, Jeongmoo; Park, Eunae; Lee, Ilha; Choi, Giltsu

doi:10.1016/j.molp.2015.08.005

Cited by 28 publications

(19 citation statements)

References 80 publications

(110 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Indeed, CO transcriptional activity is repressed by RUP2, and this effect is detectable at the level of reduced FT expression, FT promoter activity in transient reporter assays, and CO association with the FT promoter in ChIP assays. Interestingly, several CO-interacting proteins were described recently as negative regulators of CO transcriptional activity, acting through recruitment of TOPLESS repressor proteins or through inhibition of CO binding to target genes (Wang et al 2014(Wang et al , 2016Nguyen et al 2015;Zhang et al 2015;Graeff et al 2016;Xu et al 2016;Ordonez-Herrera et al 2018), the latter of which is similar to our findings for RUP2 activity. It is interesting to note that RUP2 binds to the N-terminal part of CO, which is comprised of two tandem B-box domains.…”

Section: Discussionsupporting

confidence: 90%

Arabidopsis RUP2 represses UVR8-mediated flowering in noninductive photoperiods

et al. 2018

View full text Add to dashboard Cite

Plants have evolved complex photoreceptor-controlled mechanisms to sense and respond to seasonal changes in day length. This ability allows plants to optimally time the transition from vegetative growth to flowering. UV-B is an important part intrinsic to sunlight; however, whether and how it affects photoperiodic flowering has remained elusive. Here, we report that, in the presence of UV-B, genetic mutation of REPRESSOR OF UV-B PHOTOMOR-PHOGENESIS 2 (RUP2) renders the facultative long day plant Arabidopsis thaliana a day-neutral plant and that this phenotype is dependent on the UV RESISTANCE LOCUS 8 (UVR8) UV-B photoreceptor. We provide evidence that the floral repression activity of RUP2 involves direct interaction with CONSTANS, repression of this key activator of flowering, and suppression of FLOWERING LOCUS T transcription. RUP2 therefore functions as an essential repressor of UVR8-mediated induction of flowering under noninductive short day conditions and thus provides a crucial mechanism of photoperiodic flowering control.

show abstract

Section: Discussionsupporting

confidence: 90%

Arabidopsis RUP2 represses UVR8-mediated flowering in noninductive photoperiods

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Similarly, Galvão et al (2012) showed that GA regulate flowering through controlling the expression of FT, TSF, and SPLs in a day length-specific manner. Additionally, BOTRYTIS SUSCEPTIBLE1 INTERACTORs (a group of interacting partners of DELLA proteins) interact with CO, which inhibit CO to target FT (Nguyen et al, 2015). However, the exact molecular mechanisms underlying interactions of the photoperiod and GA pathways remain limited.…”

Section: Discussionmentioning

confidence: 99%

“…Accumulating evidence has indicated that the photoperiod and GA pathways coordinate to modulate flowering under LDs Porri et al, 2012;Reeves and Coupland, 2001;Hou et al, 2014;Nguyen et al, 2015). Very recently, Xu et al (2016) reported that DELLA proteins physically interact with CO, indicating a direct association between the photoperiod and GA pathways.…”

mentioning

confidence: 99%

The DELLA-CONSTANS Transcription Factor Cascade Integrates Gibberellic Acid and Photoperiod Signaling to Regulate Flowering

et al. 2016

View full text Add to dashboard Cite

Gibberellin (GA) and photoperiod pathways have recently been demonstrated to collaboratively modulate flowering under long days (LDs). However, the molecular mechanisms underlying this collaboration remain largely unclear. In this study, we found that GA-induced expression of FLOWERING LOCUS T (FT) under LDs was dependent on CONSTANS (CO), a critical transcription factor positively involved in photoperiod signaling. Mechanistic investigation revealed that DELLA proteins, a group of crucial repressors in GA signaling, physically interacted with CO. The DELLA-CO interactions repressed the transcriptional function of CO protein. Genetic analysis demonstrated that CO acts downstream of DELLA proteins to regulate flowering. Disruption of CO rescued the earlier flowering phenotype of the gai-t6 rga-t2 rgl1-1 rgl2-1 mutant (dellap), while a gain-of-function mutation in GA INSENSITIVE (GAI, a member of the DELLA gene) repressed the earlier flowering phenotype of CO-overexpressing plants. In addition, the accumulation of DELLA proteins and mRNAs was rhythmic, and REPRESSOR OF GA1-3 protein was noticeably decreased in the long-day afternoon, a time when CO protein is abundant. Collectively, these results demonstrate that the DELLA-CO cascade inhibits CO/FT-mediated flowering under LDs, which thus provide evidence to directly integrate GA and photoperiod signaling to synergistically modulate flowering under LDs.

show abstract

“…The expression profile of REPRESSOR OF GA1-3 protein, a member of the DELLA protein family, diurnally oscillates with a trough in the afternoon when CO induces FT expression. GA also regulates CO function through BOTRYTIS SUSCEPTIBLE1 INTERACTOR (BOI; Nguyen et al, 2015). BOI interacts with CO but it does not affect CO protein stability; instead, it influences the DNA binding ability of CO to the FT promoter.…”

Section: Transcriptional Regulation Of Ftmentioning

confidence: 99%

Circadian Clock and Photoperiodic Flowering in Arabidopsis: CONSTANS Is a Hub for Signal Integration

2016

View full text Add to dashboard Cite

Plants sense changes in day length (= photoperiod) as a reliable seasonal cue to regulate important developmental transitions such as flowering. Integration of various external light information into the circadian clock-controlled mechanisms enables plants to precisely measure photoperiod changes in the surrounding environment. The core mechanism of photoperiodic measurement is regulation of CONSTANS (CO) activity, which takes place in phloem companion cells in leaves. Until recently, it remained unclear whether plants possess specific variations of the clock for this regulation. Now it is known that a specific circadian timing mechanism in the vascular tissue is essential for photoperiodic flowering. In addition to spatial tissue-specific regulation, temporal regulation of CO activity is also important. The identification and characterization of multiple regulators that physically interact with CO and influence its function in the morning in long days are two recent advances in photoperiodic regulation of flowering time. It seems that CO acts as a network hub to integrate various external and internal signals into the photoperiodic flowering pathway. CO regulates the amount of FLOWERING LOCUS T (FT) transcripts and FT protein moves from companion cells of leaf phloem to the shoot apical meristem. The protein that helps long-distance transport of FT protein was also identified recently. Here, we introduce recent advances in tissue-specific variations of the circadian clock and the emerging picture of the intricate connections of transcriptional regulators through CO in the morning, which all facilitate plants knowing when to flower.Properly timing the floral transition is crucial for reproductive success. It can also influence the early development of offspring. To optimize this timing, plants constantly monitor changes in the surrounding environment. Among various environmental factors, observing changes in day length (= photoperiod) is the most reliable way for many organisms to know the specific time of year. Therefore, photoperiodic regulation is one of the major flowering time mechanisms and it has been studied since it was first reported in 1920 (Song et al., 2015). Arabidopsis (Arabidopsis thaliana), as it flowers mainly in spring, can sense lengthening days to induce flowering and became a suitable model to study photoperiodic flowering regulation. (Andrés and Coupland, 2012;Song et al., 2013;Pajoro et al., 2014;Shim and Imaizumi, 2015).In principle, photoperiodic flowering mechanisms can be divided into three parts: light input, circadian clock, and output. Light information is integrated into innate photoperiodic timing mechanisms governed by the circadian clock to induce genes that trigger flowering.

show abstract

The Arabidopsis RING Domain Protein BOI Inhibits Flowering via CO-dependent and CO-independent Mechanisms

Cited by 28 publications

References 80 publications

Arabidopsis RUP2 represses UVR8-mediated flowering in noninductive photoperiods

Arabidopsis RUP2 represses UVR8-mediated flowering in noninductive photoperiods

The DELLA-CONSTANS Transcription Factor Cascade Integrates Gibberellic Acid and Photoperiod Signaling to Regulate Flowering

Circadian Clock and Photoperiodic Flowering in Arabidopsis: CONSTANS Is a Hub for Signal Integration

Contact Info

Product

Resources

About