Loss of Function of the E1-Like-b Gene Associates With Early Flowering Under Long-Day Conditions in Soybean

As essential structural components of ATP-dependent chromatin-remodeling complex, the nucleolus-localized actin-related proteins (ARPs) play critical roles in many biological processes. Among them, ARP4 is identified as an integral subunit of chromatin remodeling complex SWR1, which is conserved in yeast, humans and plants. It was shown that RNAi mediated knock-down of Arabidopsis thaliana ARP4 (AtARP4) could affect plant development, specifically, leading to early flowering. However, so far, little is known about how ARP4 functions in the SWR1 complex in plant. Here, we identified a loss-of-function mutant of AtARP4 with a single nucleotide change from glycine to arginine, which had significantly smaller leaf size. The results from the split luciferase complementation imaging (LCI) and yeast two hybrid (Y2H) assays confirmed its physical interaction with the scaffold and catalytic subunit of SWR1 complex, photoperiod-independent early flowering 1 (PIE1). Furthermore, mutation of AtARP4 caused altered transcription response of hundreds of genes, in which the number of up-regulated differentially expressed genes (DEGs) was much larger than those down-regulated. Although most DEGs in atarp4 are related to plant defense and response to hormones such as salicylic acid, overall, it has less overlapping with other swr1 mutants and the hta9 hta11 double-mutant. In conclusion, our results reveal that AtARP4 is important for plant growth and such an effect is likely attributed to its repression on gene expression, typically at defense-related loci, thus providing some evidence for the coordination of plant growth and defense, while the regulatory patterns and mechanisms are distinctive from other SWR1 complex components.

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Retroelement insertions at the MedicagoFTa1locus inspringmutants eliminate vernalisation but not long-day requirements for early flowering

The Plant Journal ◽

10.1111/tpj.12315 ◽

2013 ◽

Vol 76 (4) ◽

pp. 580-591 ◽

Cited By ~ 22

Author(s):

Mauren Jaudal ◽

Chin C. Yeoh ◽

Lulu Zhang ◽

Christine Stockum ◽

Kirankumar S. Mysore ◽

...

Keyword(s):

Early Flowering ◽

Long Day

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Double loss-of-function mutation in EARLY FLOWERING 3 and CRYPTOCHROME 2 genes delays flowering under continuous light but accelerates it under long days and short days: an important role for Arabidopsis CRY2 to accelerate flowering time in continuous light

Journal of Experimental Botany ◽

10.1093/jxb/erq450 ◽

2011 ◽

Vol 62 (8) ◽

pp. 2731-2744 ◽

Cited By ~ 12

Author(s):

Rim Nefissi ◽

Yu Natsui ◽

Kana Miyata ◽

Atsushi Oda ◽

Yoshihiro Hase ◽

...

Keyword(s):

Flowering Time ◽

Continuous Light ◽

Early Flowering ◽

Loss Of Function ◽

Cryptochrome 2 ◽

Short Days

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Effect of phyB and phyC loss-of-function mutations on the wheat transcriptome under short and long day photoperiods

BMC Plant Biology ◽

10.1186/s12870-020-02506-0 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Nestor Kippes ◽

Carl VanGessel ◽

James Hamilton ◽

Ani Akpinar ◽

Hikmet Budak ◽

...

Keyword(s):

Loss Of Function ◽

Long Day ◽

Wheat Transcriptome

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The early-flowering mutant efs is involved in the autonomous promotion pathway of Arabidopsis thaliana

Development ◽

10.1242/dev.126.21.4763 ◽

1999 ◽

Vol 126 (21) ◽

pp. 4763-4770 ◽

Cited By ~ 3

Author(s):

W.J. Soppe ◽

L. Bentsink ◽

M. Koornneef

Keyword(s):

Arabidopsis Thaliana ◽

Flowering Time ◽

Double Mutant ◽

Plant Size ◽

Early Flowering ◽

Wild Type ◽

Late Flowering ◽

Long Day ◽

Short Days ◽

Transition To Flowering

The transition to flowering is a crucial moment in a plant's life cycle of which the mechanism has only been partly revealed. In a screen for early flowering, after mutagenesis of the late-flowering fwa mutant of Arabidopsis thaliana, the early flowering in short days (efs) mutant was identified. Under long-day light conditions, the recessive monogenic efs mutant flowers at the same time as wild type but, under short-day conditions, the mutant flowers much earlier. In addition to its early-flowering phenotype, efs has several pleiotropic effects such as a reduction in plant size, fertility and apical dominance. Double mutant analysis with several late-flowering mutants from the autonomous promotion (fca and fve) and the photoperiod promotion (co, fwa and gi) pathways of flowering showed that efs reduces the flowering time of all these mutants. However, efs is completely epistatic to fca and fve but additive to co, fwa and gi, indicating that EFS is an inhibitor of flowering specifically involved in the autonomous promotion pathway. A vernalisation treatment does not further reduce the flowering time of the efs mutant, suggesting that vernalisation promotes flowering through EFS. By comparing the length of the juvenile and adult phases of vegetative growth for wild-type, efs and the double mutant plants, it is apparent that efs mainly reduces the length of the adult phase.

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Analysis of early-flowering genes at barley chromosome 2H expands the repertoire of mutant alleles at the Mat-c locus

Plant Cell Reports ◽

10.1007/s00299-019-02472-4 ◽

2019 ◽

Vol 39 (1) ◽

pp. 47-61

Author(s):

Izabela Matyszczak ◽

Marta Tominska ◽

Shakhira Zakhrabekova ◽

Christoph Dockter ◽

Mats Hansson

Keyword(s):

Pericentromeric Region ◽

Early Flowering ◽

Antirrhinum Majus ◽

Optimal Timing ◽

Near Isogenic Lines ◽

Loss Of Function ◽

Yield Improvement ◽

X Ray ◽

Nonsynonymous Substitutions ◽

Flowering Genes

Abstract Key message Analyses of barley mat-c loss of function mutants reveal deletions, splice-site mutations and nonsynonymous substitutions in a key gene regulating early flowering. Abstract Optimal timing of flowering is critical for reproductive success and crop yield improvement. Several major quantitative trait loci for flowering time variation have been identified in barley. In the present study, we analyzed two near-isogenic lines, BW507 and BW508, which were reported to carry two independent early-flowering mutant loci, mat-b.7 and mat-c.19, respectively. Both introgression segments are co-localized in the pericentromeric region of chromosome 2H. We mapped the mutation in BW507 to a 31 Mbp interval on chromosome 2HL and concluded that BW507 has a deletion of Mat-c, which is an ortholog of Antirrhinum majus CENTRORADIALIS (AmCEN) and Arabidopsis thaliana TERMINAL FLOWER1 (AtTFL1). Contrary to previous reports, our data showed that both BW507 and BW508 are Mat-c deficient and none of them are mat-b.7 derived. This work complements previous studies by identifying the uncharacterized mat-c.19 mutant and seven additional mat-c mutants. Moreover, we explored the X-ray structure of AtTFL1 for prediction of the functional effects of nonsynonymous substitutions caused by mutations in Mat-c.

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Improved Plant Nitrate Status Involves in Flowering Induction by Extended Photoperiod

Frontiers in Plant Science ◽

10.3389/fpls.2021.629857 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jia Yuan Ye ◽

Wen Hao Tian ◽

Miao Zhou ◽

Qing Yang Zhu ◽

Wen Xin Du ◽

...

Keyword(s):

Nitrate Uptake ◽

Floral Induction ◽

Nitrate Assimilation ◽

Early Flowering ◽

Nitrate Transporter ◽

Loss Of Function ◽

Flowering Locus T ◽

Plant Populations ◽

Flowering Genes ◽

Photoperiodic Flowering

The floral transition stage is pivotal for sustaining plant populations and is affected by several environmental factors, including photoperiod. However, the mechanisms underlying photoperiodic flowering responses are not fully understood. Herein, we have shown that exposure to an extended photoperiod effectively induced early flowering in Arabidopsis plants, at a range of different nitrate concentrations. However, these photoperiodic flowering responses were attenuated when the nitrate levels were suboptimal for flowering. An extended photoperiod also improved the root nitrate uptake of by NITRATE TRANSPORTER 1.1 (NRT1.1) and NITRATE TRANSPORTER 2.1 (NRT2.1), whereas the loss of function of NRT1.1/NRT2.1 in the nrt1.1-1/2.1-2 mutants suppressed the expression of the key flowering genes CONSTANS (CO) and FLOWERING LOCUS T (FT), and reduced the sensitivity of the photoperiodic flowering responses to elevated levels of nitrate. These results suggest that the upregulation of root nitrate uptake during extended photoperiods, contributed to the observed early flowering. The results also showed that the sensitivity of photoperiodic flowering responses to elevated levels of nitrate, were also reduced by either the replacement of nitrate with its assimilation intermediate product, ammonium, or by the dysfunction of the nitrate assimilation pathway. This indicates that nitrate serves as both a nutrient source for plant growth and as a signaling molecule for floral induction during extended photoperiods.

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Effect of phyB and phyC loss-of-function mutations on the wheat transcriptome under short and long day photoperiods

10.1101/2020.04.07.030197 ◽

2020 ◽

Cited By ~ 1

Author(s):

Nestor Kippes ◽

Carl VanGessel ◽

James Hamilton ◽

Ani Akpinar ◽

Hikmet Budak ◽

...

Keyword(s):

Candidate Genes ◽

Regulatory Networks ◽

Red Light ◽

Differentially Expressed ◽

Rna Seq ◽

Loss Of Function ◽

Wild Type ◽

Long Day ◽

Alternatively Spliced ◽

Null Mutants

AbstractBackgroundPhotoperiod signals provide important cues by which plants regulate their growth and development in response to predictable seasonal changes. Phytochromes, a family of red and far-red light receptors, play critical roles in regulating flowering time in response to changing photoperiods. A previous study showed that loss-of-function mutations in either PHYB or PHYC result in large delays in heading time and in the differential regulation of a large number of genes in wheat plants grown in an inductive long day (LD) photoperiod.ResultsWe found that under non-inductive short-day (SD) photoperiods, phyB-null and phyC-null mutants were taller, had a reduced number of tillers, longer and wider leaves, and headed later than wild-type plants. Unexpectedly, both mutants flowered earlier in SD than LD, the inverse response to that of wild-type plants. We observed a larger number of differentially expressed genes between mutants and wild-type under SD than under LD, and in both cases, the number was larger for phyB than for phyC. We identified subsets of differentially expressed and alternatively spliced genes that were specifically regulated by PHYB and PHYC in either SD or LD photoperiods, and a smaller set of genes that were regulated in both photoperiods. We observed significantly higher transcript levels of the flowering promoting genes VRN-A1, PPD-B1 and GIGANTEA in the phy-null mutants in SD than in LD, which suggests that they could contribute to the earlier flowering of the phy-null mutants in SD than in LD.ConclusionsOur study revealed an unexpected reversion of the wheat LD plants into SD plants in the phyB-null and phyC-null mutants and identified candidate genes potentially involved in this phenomenon. Our RNA-seq data provides insight into light signaling pathways in inductive and non-inductive photoperiods and a set of candidate genes to dissect the underlying developmental regulatory networks in wheat.

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