Molecular cloning and biochemical characterization of two UDP-glycosyltransferases from poplar

Veljanovski, Vasko; Constabel, C. Peter

doi:10.1016/j.phytochem.2012.12.012

Cited by 21 publications

(18 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, two UGTs are repressed by MYB182, including UGT78M1, an enzyme that we had found to be induced in Melampsora medusae-infected poplar leaves (Miranda et al, 2007). However, the recombinant UGT78M1 protein was not active with any anthocyanin, flavonol, or flavan-3-ol substrate that we tested, so its biochemical function remains undefined (Veljanovski and Constabel, 2013). The functions of the other UGT are also unknown; however, it is expressed in herbivore-stressed poplars (Ralph et al, 2006).…”

Section: Myb182 Is a Repressor That Reduces Pa And Anthocyanin Accumumentioning

confidence: 92%

The MYB182 Protein Down-Regulates Proanthocyanidin and Anthocyanin Biosynthesis in Poplar by Repressing Both Structural and Regulatory Flavonoid Genes

2015

Self Cite

View full text Add to dashboard Cite

Trees in the genus Populus (poplar) contain phenolic secondary metabolites including the proanthocyanidins (PAs), which help to adapt these widespread trees to diverse environments. The transcriptional activation of PA biosynthesis in response to herbivory and ultraviolet light stress has been documented in poplar leaves, and a regulator of this process, the R2R3-MYB transcription factor MYB134, has been identified. MYB134-overexpressing transgenic plants show a strong high-PA phenotype. Analysis of these transgenic plants suggested the involvement of additional MYB transcription factors, including repressor-like MYB factors. Here, MYB182, a subgroup 4 MYB factor, was found to act as a negative regulator of the flavonoid pathway. Overexpression of MYB182 in hairy root culture and whole poplar plants led to reduced PA and anthocyanin levels as well as a reduction in the expression of key flavonoid genes. Similarly, a reduced accumulation of transcripts of a MYB PA activator and a basic helix-loop-helix cofactor was observed in MYB182-overexpressing hairy roots. Transient promoter activation assays in poplar cell culture demonstrated that MYB182 can disrupt transcriptional activation by MYB134 and that the basic helix-loop-helix-binding motif of MYB182 was essential for repression. Microarray analysis of transgenic plants demonstrated that down-regulated targets of MYB182 also include shikimate pathway genes. This work shows that MYB182 plays an important role in the fine-tuning of MYB134-mediated flavonoid metabolism.

show abstract

Section: Myb182 Is a Repressor That Reduces Pa And Anthocyanin Accumumentioning

confidence: 92%

The MYB182 Protein Down-Regulates Proanthocyanidin and Anthocyanin Biosynthesis in Poplar by Repressing Both Structural and Regulatory Flavonoid Genes

2015

Self Cite

View full text Add to dashboard Cite

show abstract

“…; Fukuchi-Mizutani et al, 2011). However, PtF3GTIa-2, which does not accept any flavonoids as a substrate, is also grouped into the UGT78Ia subgroup (Veljanovski and Constabel, 2013). The UGT78Ib group contains characterized UGT78 genes showing activity toward anthocyanins and flavonols, including VvF3GT1b in grapevine (Ford et al, 1998), AtF3GT1b-4 in Arabidopsis (Kubo et al, 2007), RhF3T1b in rose (Fukuchi-Mizutani et al, 2011), and FaF3GT1b in strawberry (Griesser et al, 2008), but two Arabidopsis genes, AtF3GTIb-1 and AtF3GTIb-3, within the same subgroup accept only flavonols (Jones et al, 2003;YonekuraSakakibara et al, 2008).…”

Section: Phylogenetic Relationship Between the Peach Ugt78 Genes And mentioning

confidence: 99%

“…To date, two UGT78II genes, GmF3GT2-6 in soybean and PtF3GTII-2 in poplar, have been characterized to function as a 3-O-glycosyltransferase in anthocyanin and flavonol biosynthesis (Kovinich et al, 2010;Veljanovski and Constabel, 2013). This indicates that the UGT78II genes are more closely related to the UGT78Ib genes than to the UGT78Ia genes.…”

Section: Differential Expression Pattern Of Genes Involved In Anthocymentioning

confidence: 99%

Unraveling the Mechanism Underlying the Glycosylation and Methylation of Anthocyanins in Peach

et al. 2014

View full text Add to dashboard Cite

Modification of anthocyanin plays an important role in increasing its stability in plants. Here, six anthocyanins were identified in peach (Prunus persica), and their structural diversity is attributed to glycosylation and methylation. Interestingly, peach is quite similar to the wild species Prunus ferganensis but differs from both Prunus davidiana and Prunus kansueasis in terms of anthocyanin composition in flowers. This indicates that peach is probably domesticated from P. ferganensis. Subsequently, genes responsible for both methylation and glycosylation of anthocyanins were identified, and their spatiotemporal expression results in different patterns of anthocyanin accumulation in flowers, leaves, and fruits. Two tandem-duplicated genes encoding flavonoid 3-O-glycosyltransferase (F3GT) in peach, PpUGT78A1 and PpUGT78A2, showed different activity toward anthocyanin, providing an example of divergent evolution of F3GT genes in plants. Two genes encoding anthocyanin O-methyltransferase (AOMT), PpAOMT1 and PpAOMT2, are expressed in leaves and flowers, but only PpAOMT2 is responsible for the O-methylation of anthocyanins at the 39 position in peach. In addition, our study reveals a novel branch of UGT78 genes in plants that lack the highly conserved intron 2 of the UGT gene family, with a great variation of the amino acid residue at position 22 of the plant secondary product glycosyltransferase box. Our results not only provide insights into the mechanisms underlying anthocyanin glycosylation and methylation in peach but will also aid in future attempts to manipulate flavonoid biosynthesis in peach as well as in other plants.

show abstract

“…To functionally characterize UGT71L1 and UGT78M1, we cloned their respective cDNAs into a his‐tagged protein expression vector for expression in Escherichia coli (Veljanovski and Constabel, ). The recombinant proteins were solubilized from lysed cells and purified using nickel affinity resin.…”

Section: Resultsmentioning

confidence: 99%

“…Caputi et al () list 107 UGT genes in Arabidopsis thaliana , 182 genes in soya and over 200 genes in apple. In Populus, we previously identified 171 UGT genes (Veljanovski and Constabel, ). The UGTs are systematically named based on protein sequence similarity, with the numbered UGT families defined as sharing more than 40% protein sequence identity.…”

Section: Introductionmentioning

confidence: 99%

Discovery of salicyl benzoate UDP‐glycosyltransferase, a central enzyme in poplar salicinoid phenolic glycoside biosynthesis

et al. 2020

View full text Add to dashboard Cite

SUMMARY The salicinoids are anti‐herbivore phenolic glycosides unique to the Salicaceae (Populus and Salix). They consist of a salicyl alcohol glucoside core, which is usually further acylated with benzoic, cinnamic or phenolic acids. While salicinoid structures are well known, their biosynthesis remains enigmatic. Recently, two enzymes from poplar, salicyl alcohol benzoyl transferase and benzyl alcohol benzoyl transferase, were shown to catalyze the production of salicyl benzoate, a predicted potential intermediate in salicinoid biosynthesis. Here, we used transcriptomics and co‐expression analysis with these two genes to identify two UDP‐glucose‐dependent glycosyltransferases (UGT71L1 and UGT78M1) as candidate enzymes in this pathway. Both recombinant enzymes accepted only salicyl benzoate, salicylaldehyde and 2‐hydroxycinnamic acid as glucose acceptors. Knocking out the UGT71L1 gene by CRISPR/Cas9 in poplar hairy root cultures led to the complete loss of salicortin, tremulacin and tremuloidin, and a partial reduction of salicin content. This demonstrated that UGT71L1 is required for synthesis of the major salicinoids, and suggested that an additional route can lead to salicin. CRISPR/Cas9 knockouts for UGT78M1 were not successful, and its in vivo role thus remains to be determined. Although it has a similar substrate preference and predicted structure as UGT71L1, it appears not to contribute to the synthesis of salicortin, tremulacin and tremuloidin, at least in roots. The demonstration of UGT71L1 as an enzyme of salicinoid biosynthesis will open up new avenues for the elucidation of this pathway.

show abstract

Molecular cloning and biochemical characterization of two UDP-glycosyltransferases from poplar

Cited by 21 publications

References 51 publications

The MYB182 Protein Down-Regulates Proanthocyanidin and Anthocyanin Biosynthesis in Poplar by Repressing Both Structural and Regulatory Flavonoid Genes

The MYB182 Protein Down-Regulates Proanthocyanidin and Anthocyanin Biosynthesis in Poplar by Repressing Both Structural and Regulatory Flavonoid Genes

Unraveling the Mechanism Underlying the Glycosylation and Methylation of Anthocyanins in Peach

Discovery of salicyl benzoate UDP‐glycosyltransferase, a central enzyme in poplar salicinoid phenolic glycoside biosynthesis

Contact Info

Product

Resources

About