Figures (5)  Tables (1)

    • Figure 1. 

      The nomenclature system for UGT genes.

    • Figure 2. 

      Sugar donors for glycosyltransferase.

    • Figure 3. 

      The numbers of total UGTs found in different plants species that have been published in public databases. For each group (i.e. column), the color scale is drawn according to the following ratio (shown in Supplementary Table S1 & S2), the percentage of UGTs group compared with the total UGTs within a given taxon/the percentage of UGTs group compared with the total UGTs within the taxon where the group is first identified.

    • Figure 4. 

      The constructed phylogenetic tree of UGT71s includes glycosyltransferases participating in metabolites such as glycosides. Sequences from different plant species were gathered from the GenBank protein database. UGT genes from Arabidopsis were utilized as a reference for UGT families. A tree was built utilizing the maximum-likelihood method with 1,000 bootstrap replications.

    • Figure 5. 

      Roles of UGT71s in plant response to stresses. Among the biological processes in which UGT71s are involved are glycosylation of secondary metabolites (mainly triterpenoids and flavonoids) and glycosylation of phytohormones. In addition, this chemical modification plays a role in the response to plant fitness, thus helping plants to adapt to changing environments.

    • UGT isoform Plant species Substrate(s) Action Physiological effects Ref.
      UGT71C5 Arabidopsis thaliana ABA Knockdown Drought tolerance and delayed seed germination [41]
      UGT71B6 Arabidopsis thaliana ABA Overexpression Higher tolerance to salt, freezing and drought stresses [42]
      UGT71B7 Arabidopsis thaliana ABA Knockdown Drought tolerance during germination [42]
      UGT71B8 Arabidopsis thaliana ABA Knockdown Drought tolerance during germination [42]
      UGT71C3 Arabidopsis thaliana MeSA Knockout Pseudomonas syringae infection resistance and increase in MeSA and SA levels [39]
      FaGT6 Fragaria × ananassa Quercetin and kaempferol In vitro catalytic
      activities      		 Taking over an additional role in the detoxification of xenobiotics [43]
      UGT71W2 Fragaria × ananassa 1-naphthol Silenced Increasing stability and water solubility of natural products [40]
      UGT71K3 Fragaria × ananassa Acylphloroglucinol Silenced Improving fruit quality [44]
      UGT71A33/34 Fragaria × ananassa 3-hydroxycoumarin In vitro catalytic
      activities      		 Contributing to the glycosylation of flavonols, xenobiotics [40]
      UGT71A59 Camellia sinensis Eugenol In vitro and in vivo catalytic activities Enhancing cold and drought tolerance of tea plants [45]
      UGT71C1 Arabidopsis thaliana Lignan Knockout Increased resistance to oxidative stress [46]
      UGT71C4 Cotton Naringenin Overexpression Controls the flux of phenylpropanoid metabolism [47]
      UGT71B1 Arabidopsis thaliana Flavonoids In vitro catalytic
      activities      		 Enhancement of metabolite content Increase in their stable storage in plants [46]
      MtUGT71G1 Medicago truncatula Hederagenin Mutation Beneficial to plant defence [48]
      UGT71K1 Malus × domestica Phloretin In vitro catalytic activities Enhance plant disease resistance [49]
      PgUGT1/2 Panax ginseng Ginsenosides In vitro catalytic activities Enhancement of metabolite content [48]
      UGT71A27 Panax ginseng Dammarane In vitro catalytic activities Increased stable storage in plants [48]
      MpMUGT3 Mentha × piperita Menthol In vitro catalytic activities Protects cells from terpenoid toxicity [50]
      CtUGT3 Carthamus
      tinctorius L.      		 Kaempferol Overexpression Enhancing the content of medicinal kaempferol glycosides [51]

      Table 1. 

      The impact on the expression/activity of UGT71s in plants with known substrate(s).