Dataset Information

Expression of flavonoid 3'-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize.

ABSTRACT:

Background

The maize (Zea mays) red aleurone1 (pr1) encodes a CYP450-dependent flavonoid 3'-hydroxylase (ZmF3'H1) required for the biosynthesis of purple and red anthocyanin pigments. We previously showed that Zmf3'h1 is regulated by C1 (Colorless1) and R1 (Red1) transcription factors. The current study demonstrates that, in addition to its role in anthocyanin biosynthesis, the Zmf3'h1 gene also participates in the biosynthesis of 3-deoxyflavonoids and phlobaphenes that accumulate in maize pericarps, cob glumes, and silks. Biosynthesis of 3-deoxyflavonoids is regulated by P1 (Pericarp color1) and is independent from the action of C1 and R1 transcription factors.

Results

In maize, apiforol and luteoforol are the precursors of condensed phlobaphenes. Maize lines with functional alleles of pr1 and p1 (Pr1;P1) accumulate luteoforol, while null pr1 lines with a functional or non-functional p1 allele (pr1;P1 or pr1;p1) accumulate apiforol. Apiforol lacks a hydroxyl group at the 3'-position of the flavylium B-ring, while luteoforol has this hydroxyl group. Our biochemical analysis of accumulated compounds in different pr1 genotypes showed that the pr1 encoded ZmF3'H1 has a role in the conversion of mono-hydroxylated to bi-hydroxylated compounds in the B-ring. Steady state RNA analyses demonstrated that Zmf3'h1 mRNA accumulation requires a functional p1 allele. Using a combination of EMSA and ChIP experiments, we established that the Zmf3'h1 gene is a direct target of P1. Highlighting the significance of the Zmf3'h1 gene for resistance against biotic stress, we also show here that the p1 controlled 3-deoxyanthocyanidin and C-glycosyl flavone (maysin) defence compounds accumulate at significantly higher levels in Pr1 silks as compared to pr1 silks. By virtue of increased maysin synthesis in Pr1 plants, corn ear worm larvae fed on Pr1; P1 silks showed slower growth as compared to pr1; P1 silks.

Conclusions

Our results show that the Zmf3'h1 gene participates in the biosynthesis of phlobaphenes and agronomically important 3-deoxyflavonoid compounds under the regulatory control of P1.

SUBMITTER: Sharma M

PROVIDER: S-EPMC3509002 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Expression of flavonoid 3'-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize.

Sharma Mandeep M Chai Chenglin C Morohashi Kengo K Grotewold Erich E Snook Maurice E ME Chopra Surinder S

BMC plant biology 20121101

<h4>Background</h4>The maize (Zea mays) red aleurone1 (pr1) encodes a CYP450-dependent flavonoid 3'-hydroxylase (ZmF3'H1) required for the biosynthesis of purple and red anthocyanin pigments. We previously showed that Zmf3'h1 is regulated by C1 (Colorless1) and R1 (Red1) transcription factors. The current study demonstrates that, in addition to its role in anthocyanin biosynthesis, the Zmf3'h1 gene also participates in the biosynthesis of 3-deoxyflavonoids and phlobaphenes that accumulate in mai ...[more]

PMID: 23113982

Similar Datasets

Project description:Background:Anthocyanin compounds playing multiple biological functions can be synthesized in different parts of barley (Hordeum vulgare L.) plant. The diversity of anthocyanin molecules is related with branching the pathway to alternative ways in which dihydroflavonols may be modified either with the help of flavonoid 3'-hydroxylase (F3'H) or flavonoid 3',5'-hydroxylase (F3'5'H)-the cytochrome P450-dependent monooxygenases. The F3'H and F3'5'H gene families are among the least studied anthocyanin biosynthesis structural genes in barley. The aim of this study was to identify and characterise duplicated copies of the F3'H and F3'5'H genes in the barley genome. Results:Four copies of the F3'5'H gene (on chromosomes 4HL, 6HL, 6HS and 7HS) and two copies of the F3'H gene (on chromosomes 1HL and 6HS) were identified in barley genome. These copies have either one or two introns. Amino acid sequences analysis demonstrated the presence of the flavonoid hydroxylase-featured conserved motifs in all copies of the F3'H and F3'5'H genes with the exception of F3'5'H-3 carrying a loss-of-function mutation in a conservative cytochrome P450 domain. It was shown that the divergence between F3'H and F3'5'H genes occurred 129 million years ago (MYA) before the emergence of monocot and dicot plant species. The F3'H copy approximately occurred 80 MYA; the appearance of F3'5'H copies occurred 8, 36 and 91 MYA. qRT-PCR analysis revealed the tissue-specific activity for some copies of the studied genes. The F3'H-1 gene was transcribed in aleurone layer, lemma and pericarp (with an increased level in the coloured pericarp), whereas the F3'H-2 gene was expressed in stems only. The F3'5'H-1 gene was expressed only in the aleurone layer, and in a coloured aleurone its expression was 30-fold higher. The transcriptional activity of F3'5'H-2 was detected in different tissues with significantly higher level in uncoloured genotype in contrast to coloured ones. The F3'5'H-3 gene expressed neither in stems nor in aleurone layer, lemma and pericarp. The F3'5'H-4 gene copy was weakly expressed in all tissues analysed. Conclusion:F3'H and F3'5'H-coding genes involved in anthocyanin synthesis in H. vulgare were identified and characterised, from which the copies designated F3'H-1, F3'H-2, F3'5'H-1 and F3'5'H-2 demonstrated tissue-specific expression patterns. Information on these modulators of the anthocyanin biosynthesis pathway can be used in future for manipulation with synthesis of diverse anthocyanin compounds in different parts of barley plant. Finding both the copies with tissue-specific expression and a copy undergoing pseudogenization demonstrated rapid evolutionary events tightly related with functional specialization of the duplicated members of the cytochrome P450-dependent monooxygenases gene families.

Project description:BACKGROUND:Structural genes of the phenyl-propanoid pathway which encode flavonoid 3'- and 3',5'-hydroxylases (F3'H and F3'5'H) have long been invoked to explain the biosynthesis of cyanidin- and delphinidin-based anthocyanin pigments in the so-called red cultivars of grapevine. The relative proportion of the two types of anthocyanins is largely under genetic control and determines the colour variation among red/purple/blue berry grape varieties and their corresponding wines. RESULTS:Gene fragments of VvF3'H and VvF3'5'H, that were isolated from Vitis vinifera 'Cabernet Sauvignon' using degenerate primers designed on plant homologous genes, translated into 313 and 239 amino acid protein fragments, respectively, with up to 76% and 82% identity to plant CYP75 cytochrome P450 monooxygenases. Putative function was assigned on the basis of sequence homology, expression profiling and its correlation with metabolite accumulation at ten different ripening stages. At the onset of colour transition, transcriptional induction of VvF3'H and VvF3'5'H was temporally coordinated with the beginning of anthocyanin biosynthesis, the expression being 2-fold and 50-fold higher, respectively, in red berries versus green berries. The peak of VvF3'5'H expression was observed two weeks later concomitantly with the increase of the ratio of delphinidin-/cyanidin-derivatives. The analysis of structural genomics revealed that two copies of VvF3'H are physically linked on linkage group no. 17 and several copies of VvF3'5'H are tightly clustered and embedded into a segmental duplication on linkage group no. 6, unveiling a high complexity when compared to other plant flavonoid hydroxylase genes known so far, mostly in ornamentals. CONCLUSION:We have shown that genes encoding flavonoid 3'- and 3',5'-hydroxylases are expressed in any tissues of the grape plant that accumulate flavonoids and, particularly, in skin of ripening red berries that synthesise mostly anthocyanins. The correlation between transcript profiles and the kinetics of accumulation of red/cyanidin- and blue/delphinidin-based anthocyanins indicated that VvF3'H and VvF3'5'H expression is consistent with the chromatic evolution of ripening bunches. Local physical maps constructed around the VvF3'H and VvF3'5'H loci should help facilitate the identification of the regulatory elements of each isoform and the future manipulation of grapevine and wine colour through agronomical, environmental and biotechnological tools.

Dataset Information

Expression of flavonoid 3'-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize.

Background

Results

Conclusions

Publications

Expression of flavonoid 3'-hydroxylase is controlled by P1, the regulator of 3-deoxyflavonoid biosynthesis in maize.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets