Overexpression of GmGAMYB Accelerates the Transition to Flowering and Increases Plant Height in Soybean

The flowering time and plant height of soybean are important agronomic characters, which control the adaptability and yield of soybean. R2R3 MYB transcription factor plays an important regulatory role in plant growth and development. In this study, soybean GmGAMYB gene of R2R3-MYB type was induced by long-days (LDs). GmGAMYB showed higher transcriptional levels in the flowers, leaves and pods of soybean. Overexpression of GmGAMYB in transgenic soybean showed earlier flowering time and maturity in LDs and short-days (SDs). GmGAMYB interacted with GmGBP1 and might promote flowering time by up-regulating the expression of GmFULc gene in soybean. Moreover, the expression level of GmGAMYB was also induced by gibberellins (GAs) and the plant height of GmGAMYB-ox plants was significantly increased, which was caused by the enlargement of internode cell in stem. Furthermore, GmGAMYB overexpression led to increased GA sensitivity in the hypocotyl of soybean seedlings compared with WT. GmGAMYB may be a positive regulator of GA response of promoting plant height by up-regulating the expression of GmGA20ox gene in soybean. Together, our studies preliminarily showed that the partial functions of GmGAMYB in regulating flowering time and GA pathway.

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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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R2R3 MYB transcription factor PtrMYB192 regulates flowering time in Arabidopsis by activating FLOWERING LOCUS C

Journal of Plant Biology ◽

10.1007/s12374-013-0135-1 ◽

2013 ◽

Vol 56 (4) ◽

pp. 243-250 ◽

Cited By ~ 8

Author(s):

Shanda Liu ◽

Xiaoping Wang ◽

Eryang Li ◽

Carl J. Douglas ◽

Jin-Gui Chen ◽

...

Keyword(s):

Transcription Factor ◽

Flowering Time ◽

Myb Transcription Factor ◽

Flowering Locus C ◽

Flowering Locus ◽

R2r3 Myb

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Regulation of flowering time in chrysanthemum by the R2R3 MYB transcription factor CmMYB2 is associated with changes in gibberellin metabolism

Horticulture Research ◽

10.1038/s41438-020-0317-1 ◽

2020 ◽

Vol 7 (1) ◽

Cited By ~ 1

Author(s):

Lu Zhu ◽

Yunxiao Guan ◽

Yanan Liu ◽

Zhaohe Zhang ◽

Muhammad Abuzar Jaffar ◽

...

Keyword(s):

Transcription Factor ◽

Flowering Time ◽

Myb Transcription Factor ◽

Gibberellin Metabolism ◽

R2r3 Myb

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A single nucleotide polymorphism in an R2R3 MYB transcription factor gene triggers the male sterility in soybean ms6 (Ames1)

Theoretical and Applied Genetics ◽

10.1007/s00122-021-03920-0 ◽

2021 ◽

Author(s):

Junping Yu ◽

Guolong Zhao ◽

Wei Li ◽

Ying Zhang ◽

Peng Wang ◽

...

Keyword(s):

Transcription Factor ◽

Glycine Max ◽

Male Sterility ◽

Bulked Segregant Analysis ◽

Soybean Protein ◽

Anther Development ◽

Hybrid Breeding ◽

Myb Transcription Factor ◽

Male Sterile ◽

R2r3 Myb

Abstract Key message Identification and functional analysis of the male sterile gene MS6 in Glycine max. Abstract Soybean (Glycine max (L.) Merr.) is an important crop providing vegetable oil and protein. The male sterility-based hybrid breeding is a promising method for improving soybean yield to meet the globally growing demand. In this research, we identified a soybean genic male sterile locus, MS6, by combining the bulked segregant analysis sequencing method and the map-based cloning technology. MS6, highly expressed in anther, encodes an R2R3 MYB transcription factor (GmTDF1-1) that is homologous to Tapetal Development and Function 1, a key factor for anther development in Arabidopsis and rice. In male sterile ms6 (Ames1), the mutant allele contains a missense mutation, leading to the 76th leucine substituted by histidine in the DNA binding domain of GmTDF1-1. The expression of soybean MS6 under the control of the AtTDF1 promoter could rescue the male sterility of attdf1 but ms6 could not. Additionally, ms6 overexpression in wild-type Arabidopsis did not affect anther development. These results evidence that GmTDF1-1 is a functional TDF1 homolog and L76H disrupts its function. Notably, GmTDF1-1 shows 92% sequence identity with another soybean protein termed as GmTDF1-2, whose active expression also restored the fertility of attdf1. However, GmTDF1-2 is constitutively expressed at a very low level in soybean, and therefore, not able to compensate for the MS6 deficiency. Analysis of the TDF1-involved anther development regulatory pathway showed that expressions of the genes downstream of TDF1 are significantly suppressed in ms6, unveiling that GmTDF1-1 is a core transcription factor regulating soybean anther development.

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Novel Loci Control Variation in Reproductive Timing inArabidopsis thalianain Natural Environments

Genetics ◽

10.1093/genetics/162.4.1875 ◽

2002 ◽

Vol 162 (4) ◽

pp. 1875-1884 ◽

Cited By ~ 5

Author(s):

Cynthia Weinig ◽

Mark C Ungerer ◽

Lisa A Dorn ◽

Nolan C Kane ◽

Yuko Toyonaga ◽

...

Keyword(s):

Genetic Basis ◽

Allelic Variation ◽

Developmental Pathways ◽

Natural Environments ◽

Reproductive Timing ◽

Controlled Environments ◽

Photoperiod Pathway ◽

Differential Involvement ◽

Short Days ◽

Transition To Flowering

AbstractMolecular biologists are rapidly characterizing the genetic basis of flowering in model species such as Arabidopsis thaliana. However, it is not clear how the developmental pathways identified in controlled environments contribute to variation in reproductive timing in natural ecological settings. Here we report the first study of quantitative trait loci (QTL) for date of bolting (the transition from vegetative to reproductive growth) in A. thaliana in natural seasonal field environments and compare the results with those obtained under typical growth-chamber conditions. Two QTL specific to long days in the chamber were expressed only in spring-germinating cohorts in the field, and two loci specific to short days in the chamber were expressed only in fall-germinating cohorts, suggesting differential involvement of the photoperiod pathway in different seasonal environments. However, several other photoperiod-specific QTL with large effects in controlled conditions were undetectable in natural environments, indicating that expression of allelic variation at these loci was overridden by environmental factors specific to the field. Moreover, a substantial number of QTL with major effects on bolting date in one or more field environments were undetectable under controlled environment conditions. These novel loci suggest the involvement of additional genes in the transition to flowering under ecologically relevant conditions.

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Inter-species functional compatibility of the Theobroma cacao and Arabidopsis FT orthologs: 90 million years of functional conservation of meristem identity genes

BMC Plant Biology ◽

10.1186/s12870-021-02982-y ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

S. F. Prewitt ◽

A. Shalit-Kaneh ◽

S. N. Maximova ◽

M. J. Guiltinan

Keyword(s):

Gene Expression ◽

Tissue Culture ◽

Gene Family ◽

Flowering Time ◽

Molecular Mechanisms ◽

Regulatory Pathways ◽

Late Flowering ◽

Precocious Flowering ◽

Transition To Flowering

Abstract Background In angiosperms the transition to flowering is controlled by a complex set of interacting networks integrating a range of developmental, physiological, and environmental factors optimizing transition time for maximal reproductive efficiency. The molecular mechanisms comprising these networks have been partially characterized and include both transcriptional and post-transcriptional regulatory pathways. Florigen, encoded by FLOWERING LOCUS T (FT) orthologs, is a conserved central integrator of several flowering time regulatory pathways. To characterize the molecular mechanisms involved in controlling cacao flowering time, we have characterized a cacao candidate florigen gene, TcFLOWERING LOCUS T (TcFT). Understanding how this conserved flowering time regulator affects cacao plant’s transition to flowering could lead to strategies to accelerate cacao breeding. Results BLAST searches of cacao genome reference assemblies identified seven candidate members of the CENTRORADIALIS/TERMINAL FLOWER1/SELF PRUNING gene family including a single florigen candidate. cDNA encoding the predicted cacao florigen was cloned and functionally tested by transgenic genetic complementation in the Arabidopsis ft-10 mutant. Transgenic expression of the candidate TcFT cDNA in late flowering Arabidopsis ft-10 partially rescues the mutant to wild-type flowering time. Gene expression studies reveal that TcFT is spatially and temporally expressed in a manner similar to that found in Arabidopsis, specifically, TcFT mRNA is shown to be both developmentally and diurnally regulated in leaves and is most abundant in floral tissues. Finally, to test interspecies compatibility of florigens, we transformed cacao tissues with AtFT resulting in the remarkable formation of flowers in tissue culture. The morphology of these in vitro flowers is normal, and they produce pollen that germinates in vitro with high rates. Conclusion We have identified the cacao CETS gene family, central to developmental regulation in angiosperms. The role of the cacao’s single FT-like gene (TcFT) as a general regulator of determinate growth in cacao was demonstrated by functional complementation of Arabidopsis ft-10 late-flowering mutant and through gene expression analysis. In addition, overexpression of AtFT in cacao resulted in precocious flowering in cacao tissue culture demonstrating the highly conserved function of FT and the mechanisms controlling flowering in cacao.

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