Analysis of bHLH and MYB domain proteins: species‐specific regulatory differences are caused by divergent evolution of target anthocyanin genes

Quattrocchio, Francesca; Wing, John F.; Woude, J.F. van der; Mol, J.A.; Koes, Ronald

doi:10.1046/j.1365-313x.1998.00046.x

Cited by 380 publications

(325 citation statements)

References 46 publications

Supporting

Mentioning

312

Contrasting

Unclassified

Order By: Relevance

“…the responsiveness of AtF3H but not AtDFR to MYB12 in contrast to the responsiveness of ZmDFR but not ZmF3H to ZmP, probably reflects the divergent evolution of the promoter sequences of these two genes, constituting the basis for the observed metabolic difference between maize and Arabidopsis. A similar differential regulation has also been described for the CHS promoter between maize and P. hybrida (Quattrocchio et al, 1998).…”

Section: Myb12 and Zmp Share Fundamental Functional Characteristicssupporting

confidence: 73%

The Arabidopsis Transcription Factor MYB12 Is a Flavonol-Specific Regulator of Phenylpropanoid Biosynthesis

et al. 2005

View full text Add to dashboard Cite

Comprehensive functional data on plant R2R3-MYB transcription factors is still scarce compared to the manifold of their occurrence. Here, we identified the Arabidopsis (Arabidopsis thaliana) R2R3-MYB transcription factor MYB12 as a flavonolspecific activator of flavonoid biosynthesis. Transient expression in Arabidopsis protoplasts revealed a high degree of functional similarity between MYB12 and the structurally closely related factor P from maize (Zea mays). Both displayed similar target gene specificity, and both activated target gene promoters only in the presence of a functional MYB recognition element. The genes encoding the flavonoid biosynthesis enzymes chalcone synthase, chalcone flavanone isomerase, flavanone 3-hydroxylase, and flavonol synthase were identified as target genes. Hence, our observations further add to the general notion of a close relationship between structure and function of R2R3-MYB factors. High-performance liquid chromatography analyses of myb12 mutant plants and MYB12 overexpression plants demonstrate a tight linkage between the expression level of functional MYB12 and the flavonol content of young seedlings. Quantitative real time reverse transcription-PCR using these mutant plants showed MYB12 to be a transcriptional regulator of CHALCONE SYNTHASE and FLAVONOL SYNTHASE in planta, the gene products of which are indispensable for the biosynthesis of flavonols.

show abstract

Section: Myb12 and Zmp Share Fundamental Functional Characteristicssupporting

confidence: 73%

The Arabidopsis Transcription Factor MYB12 Is a Flavonol-Specific Regulator of Phenylpropanoid Biosynthesis

et al. 2005

View full text Add to dashboard Cite

show abstract

“…Previous experiments showed that the introduction of a 35S-an2 gene in the an4 Ϫ line W115 and the hybrid W115/ W59 restored pigmentation in the corolla (complementation of an2) as well as the anthers, indicating that ectopically expressed AN2 complements an4 (Quattrocchio et al, 1998). Figure 7 shows that an4 Ϫ anthers of W115/W59 contain very small amounts of dfr and an1 mRNA (lanes 13 to 15).…”

Section: Regulation Of An1 Expression By An2 and An4mentioning

confidence: 79%

anthocyanin1 of Petunia Encodes a Basic Helix-Loop-Helix Protein That Directly Activates Transcription of Structural Anthocyanin Genes

Spelt¹,

Quattrocchio²,

Mol³

et al. 2000

The Plant Cell

Self Cite

162

View full text Add to dashboard Cite

The petunia loci anthocyanin1 ( an1 ), an2 , an4 , and an11 are required for the transcription of anthocyanin biosynthetic genes in floral organs. The an2 and an11 loci were recently cloned and shown to encode a MYB-domain transcriptional activator and a cytosolic WD40 protein, respectively. Here, we report the isolation of an1 by transposon tagging. an1 encodes a new member of the basic helix-loop-helix family of transcription factors that is functionally and evolutionarily distinct from JAF13, the apparent petunia ortholog of maize RED1 and snapdragon DELILA. We provide genetic evidence that the transcription factors encoded by an1 , an2 , and an4 operate in an unexpectedly complex regulatory hierarchy. In leaves, ectopic expression of AN2 induces an1 expression, whereas in anthers, an1 expression depends on an4 , encoding (or controlling) a MYB protein that is paralogous to AN2. Experiments with transgenic plants expressing a post-translationally controlled AN1-GLUCOCORTICOID RECEPTOR fusion protein indicated that independent of protein synthesis, AN1 directly activates the expression of the dfrA gene encoding the enzyme dihydroflavonol 4-reductase and of Pmyb27 encoding a MYB-domain protein of unknown function.

show abstract

“…In addition, transient assays on immature maize kernels demonstrate that TT2 can substitute efficiently for C1 when used in combination with B-Peru (P. Perez, personal communication), thus indicating that C1 and TT2 activate the same target genes in the maize anthocyanin pathway. Strikingly, TT2 displays a lower amino acid conservation with the petunia AN2 MYB factor, although these two proteins appear to regulate similar sets of flavonoid structural genes in their respective hosts (Quattrocchio et al, 1993(Quattrocchio et al, , 1998(Quattrocchio et al, , 1999. …”

mentioning

confidence: 99%

The Arabidopsis TT2 Gene Encodes an R2R3 MYB Domain Protein That Acts as a Key Determinant for Proanthocyanidin Accumulation in Developing Seed

Nési¹

2001

The Plant Cell Online

294

389

View full text Add to dashboard Cite

In Arabidopsis, proanthocyanidins specifically accumulate in the endothelium during early seed development. At least three TRANSPARENT TESTA ( TT ) genes, TT2 , TT8 , and TTG1 , are necessary for the normal expression of several flavonoid structural genes in immature seed, such as DIHYDROFLAVONOL-4-REDUCTASE and BANYULS ( BAN ). TT8 and TTG1 were characterized recently and found to code for a basic helix-loop-helix domain transcription factor and a WDrepeat-containing protein, respectively. Here the molecular cloning of the TT2 gene was achieved by T-DNA tagging. TT2 encoded an R2R3 MYB domain protein with high similarity to the rice OsMYB3 protein and the maize COLORLESS1 factor. A TT2-green fluorescent protein fusion protein was located mostly in the nucleus, in agreement with the regulatory function of the native TT2 protein. TT2 expression was restricted to the seed during early embryogenesis, consistent with BAN expression and the proanthocyanidin deposition profile. Finally, in gain-of-function experiments, TT2 was able to induce ectopic expression of BAN in young seedlings and roots in the presence of a functional TT8 protein. Therefore, our results strongly suggest that stringent spatial and temporal BAN expression, and thus proanthocyanidin accumulation, are determined at least partially by TT2. INTRODUCTIONFlavonoids are secondary metabolites that are unique to higher plants. They are well known for the red, purple, and brown pigmentation they give to flowers, fruit, and seed. Flavonoids fulfill numerous physiological functions during plant life and also serve as beneficial micronutrients in human and animal diets (reviewed by Koes et al., 1994;Shirley, 1996;Mol et al., 1998;Harborne and Williams, 2000). Arabidopsis contains three major classes of flavonoids: the anthocyanins (red to purple pigments), the flavonols (colorless to pale yellow pigments), and the proanthocyanidins (colorless pigments that turn to brown), which also are known as condensed tannins (Figure 1). Anthocyanins and flavonols are synthesized in vegetative parts, whereas flavonols and proanthocyanidins accumulate in seed (Chapple et al., 1994).As shown in Figure 1, the different flavonoid subpathways share common initial biosynthetic steps, including synthesis of naringenin chalcone by chalcone synthase (CHS), conversion of naringenin chalcone to naringenin by chalcone isomerase (CHI), and subsequent hydroxylations of naringenin by flavanone 3-hydroxylase (F3H) and flavonoid 3 Ј -hydroxylase (F3 Ј H). Genetic and molecular study of flavonoid biosynthesis in Arabidopsis has revealed that the CHS, CHI, F3H, and F3 Ј H enzymes are encoded by the TRANSPAR-ENT TESTA4 ( TT4 ), TT5 , TT6 , and TT7 genes, respectively (Shirley et al., , 1995Wisman et al., 1998;Schoenbohm et al., 2000). Then, an NADPH-dependent dihydroflavonol reductase (DFR), encoded by the TT3 gene in Arabidopsis , leads to the production of flavan-3,4-diols (leucoanthocyanidins), which are the last common intermediates in anthocyanin and proanthocyanidin biosynthesis. Leu...

show abstract

Analysis of bHLH and MYB domain proteins: species‐specific regulatory differences are caused by divergent evolution of target anthocyanin genes

Cited by 380 publications

References 46 publications

The Arabidopsis Transcription Factor MYB12 Is a Flavonol-Specific Regulator of Phenylpropanoid Biosynthesis

The Arabidopsis Transcription Factor MYB12 Is a Flavonol-Specific Regulator of Phenylpropanoid Biosynthesis

anthocyanin1 of Petunia Encodes a Basic Helix-Loop-Helix Protein That Directly Activates Transcription of Structural Anthocyanin Genes

The Arabidopsis TT2 Gene Encodes an R2R3 MYB Domain Protein That Acts as a Key Determinant for Proanthocyanidin Accumulation in Developing Seed

Contact Info

Product

Resources

About