Functional divergence between soybean FLOWERING LOCUS T orthologues FT2a and FT5a in post-flowering stem growth

Abstract Genes in the FLOWERING LOCUS T (FT) family integrate external and internal signals to control various aspects of plant development. In soybean (Glycine max), FT2a and FT5a play a major role in floral induction, but their roles in post-flowering reproductive development remain undetermined. Ectopic overexpression analyses revealed that FT2a and FT5a similarly induced flowering, but FT5a was markedly more effective than FT2a for the post-flowering termination of stem growth. The down-regulation of Dt1, a soybean orthologue of Arabidopsis TERMINAL FLOWER1, in shoot apices in early growing stages of FT5a-overexpressing plants was concomitant with highly up-regulated expression of APETALA1 orthologues. The Dt2 gene, a repressor of Dt1, was up-regulated similarly by the overexpression of FT2a and FT5a, suggesting that it was not involved in the control of stem termination by FT5a. In addition to the previously reported interaction with FDL19, a homologue of the Arabidopsis bZIP protein FD, both FT2a and FT5a interacted with FDL12, but only FT5a interacted with FDL06. Our results suggest that FT2a and FT5a have different functions in the control of post-flowering stem growth. A specific interaction of FT5a with FDL06 may play a key role in determining post-flowering stem growth in soybean.

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Rootstock Affects Floral Induction in Citrus Engaging the Expression of the FLOWERING LOCUS T (CiFT)

Agriculture ◽

10.3390/agriculture11020140 ◽

2021 ◽

Vol 11 (2) ◽

pp. 140

Author(s):

Stefania Bennici ◽

Giuseppina Las Casas ◽

Gaetano Distefano ◽

Alessandra Gentile ◽

Giuseppe Lana ◽

...

Keyword(s):

Floral Induction ◽

Flower Induction ◽

Water Deficit Stress ◽

Flowering Locus T ◽

Expression Levels ◽

Yield Efficiency ◽

Flowering Locus ◽

The Relationship ◽

Inductive Period ◽

Swingle Citrumelo

In Citrus, flower induction represents the transition from vegetative to reproductive growth. The regulation of flower induction is mainly triggered by exposure to low temperatures and water-deficit stress, which activates the signaling cascade leading to an increased expression of the citrus orthologs of the FLOWERING LOCUS T (CiFT). In this study, the relationship between rootstock and flower induction under Mediterranean field conditions was investigated by monitoring the expression levels of the floral promoter CiFT2 in leaves of the pigmented sweet orange “Tarocco Scirè” grafted onto “C35” citrange and “Swingle” citrumelo rootstocks. The latter two are known to confer, respectively, high and low yield efficiency to the scion. In both rootstock/scion combinations, CiFT2 showed a seasonal expression with a peak during the inductive period in January triggered by cold temperature. The “Tarocco Scirè”/”C35” citrange combination showed the highest expression levels for CiFT2; this increased expression was correlated with yield and a higher number of flowers in the following spring, suggesting a significant effect of rootstocks on flower induction mediated by the overexpression of the CiFT2 gene.

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Floral induction in Arabidopsis thaliana by FLOWERING LOCUS T requires direct repression of BLADE-ON-PETIOLE genes by homeodomain protein PENNYWISE

PLANT PHYSIOLOGY ◽

10.1104/pp.15.00960 ◽

2015 ◽

pp. pp.00960.2015 ◽

Cited By ~ 7

Author(s):

Fernando Andres ◽

Maida Romera-Branchat ◽

Rafael Martínez-Gallegos ◽

Vipul Patel ◽

Korbinian Schneeberger ◽

...

Keyword(s):

Arabidopsis Thaliana ◽

Floral Induction ◽

Homeodomain Protein ◽

Flowering Locus T ◽

Flowering Locus

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Expression of coffee florigen CaFT1 reveals a sustained floral induction window associated with asynchronous flowering in tropical perennials

10.1101/2021.11.04.466514 ◽

2021 ◽

Author(s):

Carlos Henrique Cardon ◽

Raphael Ricon de Oliveira ◽

Victoria Lesy ◽

Thales Henrique Cherubino Ribeiro ◽

Luisa Peloso Pereira ◽

...

Keyword(s):

Floral Induction ◽

Day Length ◽

Yeast Two Hybrid ◽

Flowering Locus T ◽

Temperature Changes ◽

Regulatory Pathways ◽

The Face ◽

Flowering Locus ◽

One Year ◽

Two Hybrid

The behavior of florigen(s) and environment-influenced regulatory pathways that control flowering in tropical perennials with complex phenological cycles is poorly understood. Understanding the mechanisms underlying this process is important for food production in the face of climate change. To explore this, homologs of Arabidopsis florigen FLOWERING LOCUS T (CaFT1) and environment-related regulators CONSTANS (CO), PHYTOCHROME INTERACTING FACTOR 4 (PIF4) and FLOWERING LOCUS C (FLC) were isolated from Coffea sp. L. (Rubiaceae). Overexpression of CaFT1 in Arabidopsis showed typical early-flowering and yeast two hybrid studies indicated CaFT1 binding to bZIP floral regulator, FD, demonstrates that CaFT1 is a coffee orthologue of florigen. Expression of CaFT1 and floral regulators were evaluated over one year using three contrasting genotypes: two C. arabica and one C. canephora. All genotypes showed active CaFT1 transcription from February until October, indicating a potential window for floral induction. CaCO expression, as expected, varied over the day period and monthly with day length, whereas expression of temperature-responsive homologs, CaFLC and CaPIF4, did not correlate with temperature changes. Using coffee as a model, we suggest a continuum of floral induction that allows different starting points for floral activation, which explains developmental asynchronicity and prolonged anthesis events in tropical perennial species.

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A cis Element within Flowering Locus T mRNA Determines Its Mobility and Facilitates Trafficking of Heterologous Viral RNA

Journal of Virology ◽

10.1128/jvi.02346-08 ◽

2009 ◽

Vol 83 (8) ◽

pp. 3540-3548 ◽

Cited By ~ 55

Author(s):

Chunyang Li ◽

Ke Zhang ◽

Xianwu Zeng ◽

Stephen Jackson ◽

Yu Zhou ◽

...

Keyword(s):

Potato Virus ◽

Floral Induction ◽

Ectopic Expression ◽

Green Fluorescence Protein ◽

Systemic Infection ◽

Potato Virus X ◽

Flowering Locus T ◽

Long Distance ◽

Systemic Spread ◽

Flowering Locus

ABSTRACT The Arabidopsis flowering locus T (FT) gene encodes the mobile florigen essential for floral induction. While movement of the FT protein has been shown to occur within plants, systemic spread of FT mRNA remains to be unequivocally demonstrated. Utilizing novel RNA mobility assay vectors based on two distinct movement-defective viruses, Potato virus X and Turnip crinkle virus, and an agroinfiltration assay, we demonstrate that nontranslatable FT mRNA, independent of the FT protein, moves throughout Nicotiana benthamiana and mutant Arabidopsis plants and promotes systemic trafficking of viral and green fluorescence protein RNAs. Viral ectopic expression of FT induced flowering in the short-day N. tabacum Maryland Mammoth tobacco under long-day conditions. Recombinant Potato virus X bearing FT RNA spread and established systemic infection more quickly than the parental virus. The cis-acting element essential for RNA movement was mapped to the nucleotides 1 to 102 of the FT mRNA coding sequence. These data demonstrate that a plant self-mobile RNA molecule can mediate long-distance trafficking of heterologous RNAs and raise the possibility that FT RNA, along with the FT protein, may be involved in the spread of the floral stimulus throughout the plant.

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FLOWERING LOCUS T4 (HvFT4) delays flowering and decreases floret fertility in barley

10.1101/2020.03.26.010033 ◽

2020 ◽

Author(s):

Rebecca Pieper ◽

Filipa Tomé ◽

Maria von Korff

Keyword(s):

Flowering Time ◽

Reproductive Development ◽

Negative Regulator ◽

Flowering Locus T ◽

Time Control ◽

Photoperiodic Regulation ◽

Flowering Locus ◽

Delayed Flowering ◽

Flowering Time Control

AbstractFLOWERING LOCUS T-like genes (FT-like) control the photoperiodic regulation of flowering in many angiosperm plants. The family of FT-like genes is characterised by extensive gene duplication and subsequent diversification of FT functions which occurred independently in modern angiosperm lineages. In barley, there are 12 known FT-like genes (HvFT) but the function of most of them remains uncharacterised. This study aimed to characterise the role of HvFT4 in flowering time control and development in barley. The overexpression of HvFT4 in the spring cultivar Golden Promise delayed flowering time under long-day conditions. Microscopic dissection of the shoot apical meristem (SAM) revealed that overexpression of HvFT4 specifically delayed spikelet initiation and reduced the number of spikelet primordia and grains per spike. Furthermore, ectopic overexpression of HvFT4 was associated with floret abortion and with the downregulation of the barley MADS-box genes VRN-H1, HvBM3 and HvBM8 which promote floral development. This suggests that HvFT4 functions as a repressor of reproductive development in barley. Unraveling the genetic basis of FT-like genes can contribute to the identification of novel breeding targets to modify reproductive development and thereby spike morphology and grain yield.HighlightWe identify the FLOWERING LOCUS T (FT)-like gene HvFT4 as a negative regulator of reproductive development, spikelet initiation, floret fertility and grain number in barley.

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