Exogenous Gibberellins Induce Wheat Spike Development under Short Days Only in the Presence of <i>VERNALIZATION1</i>

Pearce, Stephen; Vanzetti, Leonardo Sebastián; Dubcovsky, Jorge

doi:10.1104/pp.113.225854

Cited by 92 publications

(106 citation statements)

References 64 publications

Supporting

Mentioning

101

Contrasting

Unclassified

Order By: Relevance

“…The regulation of hormone levels by VRN1 might influence flowering or other aspects of plant development, such as final height. For example, gibberellins accelerate inflorescence development during the longday flowering response, downstream of VRN1 (refs 41,42). VRN1 also binds to the promoters of CBF genes that play critical roles in low-temperature induction of freezing tolerance and to VRS1 (Supplementary Data 2), which regulates spike architecture 43 .…”

Section: Discussionmentioning

confidence: 99%

Direct links between the vernalization response and other key traits of cereal crops

et al. 2015

View full text Add to dashboard Cite

Transcription of the VERNALIZATION1 gene (VRN1) is induced by prolonged cold (vernalization) to trigger flowering of cereal crops, such as wheat and barley. VRN1 encodes a MADS box transcription factor that promotes flowering by regulating the expression of other genes. Here we use transcriptome sequencing (RNA-seq) and chromatin immunoprecipitation sequencing (ChIP-seq) to identify direct targets of VRN1. Over 500 genomic regions were identified as potential VRN1-binding targets by ChIP-seq. VRN1 binds the promoter of FLOWERING LOCUS T-like 1, a promoter of flowering in vernalized plants. VRN1 also targets VERNALIZATION2 and ODDSOC2, repressors of flowering that are downregulated in vernalized plants. RNA-seq identified additional VRN1 targets that might play roles in triggering flowering. Other targets of VRN1 include genes that play central roles in low-temperature-induced freezing tolerance, spike architecture and hormone metabolism. This provides evidence for direct regulatory links between the vernalization response pathway and other important traits in cereal crops.

show abstract

Section: Discussionmentioning

confidence: 99%

Direct links between the vernalization response and other key traits of cereal crops

et al. 2015

View full text Add to dashboard Cite

show abstract

“…The up-regulation of FT1 in the leaves further induces VRN1 (71), closing a positive feedback loop that accelerates flowering under LD (21,76). (Pathway D) In the apex, FT1 induces VRN1 transcription and gibberellin biosynthesis and accumulation (33). The simultaneous presence of gibberellin and VRN1 results in the up-regulation of SOC1-1 and LFY, which are required for normal wheat-spike development.…”

Section: Methodsmentioning

confidence: 99%

“…The simultaneous presence of gibberellin and VRN1 results in the up-regulation of SOC1-1 and LFY, which are required for normal wheat-spike development. The regulation of gibberellin biosynthesis in the apex by FT1 acts as a secondary LD regulatory point (33). requirement (65).…”

Section: Methodsmentioning

confidence: 99%

“…The FT1 HOPE allele has a repetitive element in the promoter region that is associated with higher FT1 transcript level than that of the wild-type allele, under both LD and SD photoperiods (32,33). Indeed, wild-type and phyC AB mutant plants carrying the FT1 HOPE allele show increased FT1 transcript levels (SI Appendix, Fig.…”

Section: Loss-of-function Mutations For Phyc Have a Strong Effect On mentioning

confidence: 99%

See 1 more Smart Citation

PHYTOCHROME C plays a major role in the acceleration of wheat flowering under long-day photoperiod

Chen¹,

et al. 2014

Proc. Natl. Acad. Sci. U.S.A.

Self Cite

182

228

View full text Add to dashboard Cite

Phytochromes are dimeric proteins that function as red and far-red light sensors influencing nearly every phase of the plant life cycle. Of the three major phytochrome families found in flowering plants, PHYTOCHROME C (PHYC) is the least understood. In Arabidopsis and rice, PHYC is unstable and functionally inactive unless it heterodimerizes with another phytochrome. However, when expressed in an Arabidopsis phy-null mutant, wheat PHYC forms signaling active homodimers that translocate into the nucleus in red light to mediate photomorphogenic responses. Tetraploid wheat plants homozygous for loss-of-function mutations in all PHYC copies (phyC AB ) flower on average 108 d later than wild-type plants under long days but only 19 d later under short days, indicating a strong interaction between PHYC and photoperiod. This interaction is further supported by the drastic down-regulation in the phyC AB mutant of the central photoperiod gene PHOTOPERIOD 1 (PPD1) and its downstream target FLOWERING LOCUS T1, which are required for the promotion of flowering under long days. These results implicate light-dependent, PHYC-mediated activation of PPD1 expression in the acceleration of wheat flowering under inductive long days. Plants homozygous for the phyC AB mutations also show altered profiles of circadian clock and clock-output genes, which may also contribute to the observed differences in heading time. Our results highlight important differences in the photoperiod pathways of the temperate grasses with those of well-studied model plant species.

show abstract

“…We developed a near-isogenic Kronos line carrying the wild-type photoperiod-sensitive Ppd-A1b allele (Kronos-PS), which flowers very late under SD. This line was developed by crossing Kronos with the tetraploid durum variety Langdon (which carries the Ppd-A1b allele) and performing three backcrosses using Kronos as the recurrent parent as described previously (Pearce et al, 2013). We also developed a second near-isogenic line of Kronos with no functional PPD1 alleles, designated hereafter as ppd1-null.…”

Section: Plant Materialsmentioning

confidence: 99%

Night-Break Experiments Shed Light on the Photoperiod1-Mediated Flowering

et al. 2017

Self Cite

View full text Add to dashboard Cite

Plants utilize variation in day length (photoperiod) to anticipate seasonal changes. They respond by modulating their growth and development to maximize seed production, which in cereal crops is directly related to yield. In wheat (Triticum aestivum), the acceleration of flowering under long days (LD) is dependent on the light induction of PHOTOPERIOD1 (PPD1) by phytochromes. Under LD, PPD1 activates FLOWERING LOCUS T1 (FT1), a mobile signaling protein that travels from the leaves to the shoot apical meristem to promote flowering. Here, we show that the interruption of long nights by short pulses of light ("night-break" [NB]) accelerates wheat flowering, suggesting that the duration of the night is critical for wheat photoperiodic response. PPD1 transcription was rapidly upregulated by NBs, and the magnitude of this induction increased with the length of darkness preceding the NB. Cycloheximide abolished the NB up-regulation of PPD1, suggesting that this process is dependent on active protein synthesis during darkness. While one NB was sufficient to induce PPD1, more than 15 NBs were required to induce high levels of FT1 expression and a strong acceleration of flowering. Multiple NBs did not affect the expression of core circadian clock genes. The acceleration of flowering by NB disappeared in ppd1-null mutants, demonstrating that this response is mediated by PPD1. The acceleration of flowering was strongest when NBs were applied in the middle of the night, suggesting that in addition to PPD1, other circadiancontrolled factors are required for the up-regulation of FT1 expression and the acceleration of flowering.Plants can anticipate diurnal and seasonal fluctuations in their environment and adjust their growth and development to coincide with favorable conditions. In flowering plants, reproductive development must be optimally timed to minimize the risk of damage to sensitive floral organs by late frosts or early high temperatures. The correct timing of this transition is a major determinant of reproductive success and, in cereal crops such as wheat (Triticum aestivum), of grain yield. Therefore, an improved understanding of the regulation of flowering time can contribute to the development of crop varieties better adapted to diverse environments. Photoperiodic flowering responses vary in different species; short-day (SD) plants and long-day (LD) plants exhibit accelerated flowering in SD and LD, respectively, while day-neutral plants exhibit similar flowering profiles irrespective of day length Allard, 1920, 1923). Plants possess complex regulatory mechanisms to perceive and respond to changes in photoperiod, which ensure that flowering occurs only under inductive conditions. The regulation of flowering time by photoperiod is best understood in Arabidopsis (Arabidopsis thaliana), a LD plant where the photoperiodic response is mainly controlled by CONSTANS (CO). CO expression is regulated by the circadian clock and peaks in the late afternoon and evening (Suárez-López et al., 2001). The CO protein is destabili...

show abstract

Exogenous Gibberellins Induce Wheat Spike Development under Short Days Only in the Presence of VERNALIZATION1

Cited by 92 publications

References 64 publications

Direct links between the vernalization response and other key traits of cereal crops

Direct links between the vernalization response and other key traits of cereal crops

PHYTOCHROME C plays a major role in the acceleration of wheat flowering under long-day photoperiod

Night-Break Experiments Shed Light on the Photoperiod1-Mediated Flowering

Contact Info

Product

Resources

About