Loss-of-function mutation of soybean R2R3 MYB transcription factor reduces flavone content and dilutes tawny pubescence color

Abstract Background Pubescence color of soybean is controlled by two genes, T and Td. In the presence of a dominant T allele, dominant and recessive alleles of the Td locus generate tawny and light tawny (or near-gray) pubescence, respectively. Flavones, responsible for pubescence color, are catalyzed by two copies of flavone synthase II genes (FNS II-1 and FNS II-2). This study was conducted to map and clone the Td gene. Results Genetic and linkage analysis using an F2 population and F3 families derived from a cross between a Clark near-isogenic line with light tawny pubescence (genotype: TT tdtd) and a Harosoy near-isogenic line with tawny pubescence (TT TdTd) revealed a single gene for pubescence color around the end of chromosome 3. Genome sequence alignment of plant introductions revealed an association between premature stop codons in Glyma.03G258700 (R2R3 MYB transcription factor) and recessive td allele. Cultivars and lines having near-gray or light tawny pubescence and a gray pubescence cultivar with td allele had premature stop codons in the gene. These results suggest that Glyma.03G258700 corresponds to the Td gene. It was predominantly expressed in pubescence. Compared to a tawny pubescence line, a near-isogenic line with td allele produced extremely small amounts of transcripts of Glyma.03G258700, FNS II-1, and FNS II-2 in pubescence. The promoter of FNS II-1 and FNS II-2 shared cis-acting regulatory elements for binding of MYB proteins. These results suggest that the wild-type of Glyma.03G258700 protein binds to the promoter of FNS II genes and upregulates their expression, resulting in increased flavone content and deeper pubescence color. In contrast, mutated Glyma.03G258700 protein fails to upregulate the expression of FNS II genes, resulting in decreased flavone content and dilute pubescence color. Conclusions This study revealed that soybean Glyma.03G258700 encoding the R2R3 MYB transcription factor corresponds to the Td gene. The wild type of MYB protein binds to the promoter of FNS II genes and upregulates their expression, resulting in higher flavone content and deeper pubescence color. Loss-of-function mutation of the gene fails to promote expression of FNS II genes, resulting in lower flavone content and dilute pubescence color.

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Loss-of-Function Mutation of Soybean R2R3 MYB Transcription Factor Dilutes Tawny Pubescence Color

Frontiers in Plant Science ◽

10.3389/fpls.2019.01809 ◽

2020 ◽

Vol 10 ◽

Author(s):

Fan Yan ◽

Stephen M. Githiri ◽

Yajing Liu ◽

Yu Sang ◽

Qingyu Wang ◽

...

Keyword(s):

Transcription Factor ◽

Myb Transcription Factor ◽

Loss Of Function ◽

R2r3 Myb ◽

Pubescence Color

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An R2R3-MYB Transcription Factor PgFLP Directly Activates PgPIN10 to Regulate the GSA of Adventitious Root in Pomegranate

10.21203/rs.3.rs-123516/v1 ◽

2020 ◽

Author(s):

Zenghui Wang ◽

Jialin Li ◽

Xuemei Yang ◽

Haixia Tang ◽

Lijuan Feng ◽

...

Keyword(s):

Transcription Factor ◽

Adventitious Root ◽

Molecular Mechanisms ◽

Lateral Roots ◽

Myb Transcription Factor ◽

Wild Type ◽

Set Point ◽

Root Gravitropism ◽

Gravity Signal ◽

R2r3 Myb

Abstract Background: The self-rooted seedling is widely used in pomegranate planting industry currently; However, the root system of self-rooted seedling is shallow and poor cold resistance. Therefore, the study of the molecular mechanisms of pomegranate adventitious root gravitropism is very important for developing deep-rooted pomegranate cultivars.Results: We report the pomegranate FOUR LIPS (PgFLP) that play an key role in regulating the gravitropic set-point angle of pomegranate adventitious root in response to gravity signal. In our study, PgFLP directly regulates the transcriptional expression of PgPIN10 by binding to its promoter, thus regulating the GSA of adventitious root in pomegranate. Additionally, the 35S::PgFLP show stronger gravitational response than wild-type, leading to a smaller GSA in Arabidopsis lateral roots, indicating that PgFLP participates in regulating the GSA of adventitious root via PgPIN10 in pomegranate. Conclusion: Our results confirm that the transcriptional regulation of PgPIN10 by R2R3-MYB transcription factor PgFLP in setting the gravitropic set-point angle of pomegranate adventitious root in response to gravity signal.

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Loss-of-function mutations affecting a specific Glycine max R2R3 MYB transcription factor result in brown hilum and brown seed coats

BMC Plant Biology ◽

10.1186/1471-2229-11-155 ◽

2011 ◽

Vol 11 (1) ◽

pp. 155 ◽

Cited By ~ 33

Author(s):

Jason D Gillman ◽

Ashley Tetlow ◽

Jeong-Deong Lee ◽

J Shannon ◽

Kristin Bilyeu

Keyword(s):

Transcription Factor ◽

Glycine Max ◽

Myb Transcription Factor ◽

Loss Of Function ◽

R2r3 Myb ◽

Seed Coats

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A Novel R2R3-MYB Transcription Factor PqMYB4 Inhibited Anthocyanin Biosynthesis in Paeonia qiui

International Journal of Molecular Sciences ◽

10.3390/ijms21165878 ◽

2020 ◽

Vol 21 (16) ◽

pp. 5878

Author(s):

Dan Huo ◽

Xiaokun Liu ◽

Yue Zhang ◽

Jingjing Duan ◽

Yanlong Zhang ◽

...

Keyword(s):

Transcription Factor ◽

Coat Color ◽

Anthocyanin Biosynthesis ◽

Myb Transcription Factor ◽

Anthocyanin Content ◽

Wild Type ◽

Tree Peony ◽

Anthocyanin Pathway ◽

Red Color ◽

R2r3 Myb

Paeonia qiui is a wild tree peony native to China. Its leaves show a clear purple-red color from the germination to the flowering stage, and it has high leaf-viewing value. A MYB transcription factor gene, designated as PqMYB4, was isolated from leaves of P. qiui based on transcriptome datas. The full-length cDNA of PqMYB4 was 693 bp, encoding 230 amino acids. Sequence alignment and phylogenetic analysis revealed that PqMYB4 was a R2R3-MYB transcription factor clustered with AtMYB4 in Arabidopsis thaliana. Moreover, it contained a C1 motif, an EAR repression motif and a TLLLFR motif in the C-terminal domains, which were unique in transcription repression MYB. Subcellular location analysis showed that PqMYB4 was located in the cell nucleus. PqMYB4 was highly expressed in the late stage of leaf development, and was negatively correlated with the anthocyanin content. The petiole of wild-type Arabidopsis seedlings was deeper in color than the transgenic lines of PqMYB4 and showed a little purple-red color. The seed coat color of Arabidopsis seeds that overexpressed PqMYB4 gene was significantly lighter than that of wild-type seeds. In transgenic Arabidopsis, the expression level of AtCHS, AtCHI, AtDFR and AtANS were down-regulated significantly. These results showed that PqMYB4 was involved in the negative regulation of anthocyanin biosynthesis in tree peony leaves, which can control the anthocyanin pathway genes. Together, these findings provide a valuable resource with which to further study the regulatory mechanism of anthocyanin biosynthesis in the leaf of P. qiui. They also benefit the molecular breeding of tree peony cultivars with colored leaf.

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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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