Four Novel Functional in Flavonoid 7--glucoside Biosynthesis Are Vital to Flavonoid Biosynthesis Shunting in Citrus

Overview

Journal Hortic Res

Publisher Oxford University Press

Date 2024 Jun 12

PMID 38863995

Authors

Ziyu Yuan

Gu Li

Huixian Zhang

Zhaoxin Peng

Wenyu Ding

Huan Wen

Hanxin Zhou

Jiwu Zeng

Jiajing Chen

Juan Xu

Affiliations

Soon will be listed here.

Abstract

Citrus fruits have abundant flavonoid glycosides (FGs), an important class of natural functional and flavor components. However, there have been few reports about the modification of UDP-glycosyltransferases (UGTs) on flavonoids in citrus. Notably, in flavonoid biosynthesis, 7--glucosylation is the initial and essential step of glycosylation prior to the synthesis of flavanone disaccharides, the most abundant and iconic FGs in citrus fruits. Here, based on the accumulation of FGs observed at the very early fruit development stage of two pummelo varieties, we screened six novel flavonoid 7--glucosyltransferase genes () transcriptomic analysis and then characterized them . The results revealed that four Cg7GlcTs possess wide catalytic activities towards various flavonoid substrates, with CgUGT89AK1 exhibiting the highest catalytic efficiency. Transient overexpression of and led to increases in FG synthesis in pummelo leaves. Interestingly, these two genes had conserved sequences and consistent functions across different germplasms. Moreover, was found to play a role in the response of citrus to Huanglongbing infection by promoting FG production. The findings improve our understanding of flavonoid 7--glucosylation by identifying the key genes, and may help improve the benefits of flavonoid biosynthesis for plants and humans in the future.

References

Chen R, Qi Q, Wang M, Li Q . Therapeutic potential of naringin: an overview. Pharm Biol. 2016; 54(12):3203-3210. DOI: 10.1080/13880209.2016.1216131. View

Shen S, Wang S, Yang C, Wang C, Zhou Q, Zhou S . Elucidation of the melitidin biosynthesis pathway in pummelo. J Integr Plant Biol. 2023; 65(11):2505-2518. DOI: 10.1111/jipb.13564. View

Bian X, Li W, Niu C, Wei W, Hu Y, Han J . A class B heat shock factor selected for during soybean domestication contributes to salt tolerance by promoting flavonoid biosynthesis. New Phytol. 2019; 225(1):268-283. DOI: 10.1111/nph.16104. View

McIntosh C, Latchinian L, Mansell R . Flavanone-specific 7-O-glucosyltransferase activity in Citrus paradisi seedlings: purification and characterization. Arch Biochem Biophys. 1990; 282(1):50-7. DOI: 10.1016/0003-9861(90)90085-d. View

Wang Z, Niu Y, Vashisth T, Li J, Madden R, Livingston T . Nontargeted metabolomics-based multiple machine learning modeling boosts early accurate detection for citrus Huanglongbing. Hortic Res. 2022; 9:uhac145. PMC: 9433982. DOI: 10.1093/hr/uhac145. View

Peters D, Constabel C . Molecular analysis of herbivore-induced condensed tannin synthesis: cloning and expression of dihydroflavonol reductase from trembling aspen (Populus tremuloides). Plant J. 2002; 32(5):701-12. DOI: 10.1046/j.1365-313x.2002.01458.x. View

Hussain S, Shi C, Guo L, Du W, Bai Y, Kamran H . Type I H+-pyrophosphatase regulates the vacuolar storage of sucrose in citrus fruit. J Exp Bot. 2020; 71(19):5935-5947. DOI: 10.1093/jxb/eraa298. View

Wang L, Guo D, Zhao G, Wang J, Zhang S, Wang C . Group IIc WRKY transcription factors regulate cotton resistance to Fusarium oxysporum by promoting GhMKK2-mediated flavonoid biosynthesis. New Phytol. 2022; 236(1):249-265. DOI: 10.1111/nph.18329. View

Zhao C, Wang F, Lian Y, Xiao H, Zheng J . Biosynthesis of citrus flavonoids and their health effects. Crit Rev Food Sci Nutr. 2018; 60(4):566-583. DOI: 10.1080/10408398.2018.1544885. View

10.

. Flavonoid biosynthesis. A colorful model for genetics, biochemistry, cell biology, and biotechnology. Plant Physiol. 2001; 126(2):485-93. PMC: 1540115. DOI: 10.1104/pp.126.2.485. View

11.

Massenti R, Lo Bianco R, Sandhu A, Gu L, Sims C . Huanglongbing modifies quality components and flavonoid content of 'Valencia' oranges. J Sci Food Agric. 2014; 96(1):73-8. DOI: 10.1002/jsfa.7061. View

12.

Schulz E, Tohge T, Zuther E, Fernie A, Hincha D . Natural variation in flavonol and anthocyanin metabolism during cold acclimation in Arabidopsis thaliana accessions. Plant Cell Environ. 2015; 38(8):1658-72. DOI: 10.1111/pce.12518. View

13.

Frydman A, Liberman R, Huhman D, Carmeli-Weissberg M, Sapir-Mir M, Ophir R . The molecular and enzymatic basis of bitter/non-bitter flavor of citrus fruit: evolution of branch-forming rhamnosyltransferases under domestication. Plant J. 2012; 73(1):166-78. DOI: 10.1111/tpj.12030. View

14.

Zhu F, Luo T, Liu C, Wang Y, Yang H, Yang W . An R2R3-MYB transcription factor represses the transformation of α- and β-branch carotenoids by negatively regulating expression of CrBCH2 and CrNCED5 in flavedo of Citrus reticulate. New Phytol. 2017; 216(1):178-192. DOI: 10.1111/nph.14684. View

15.

Wang X, Li C, Zhou Z, Zhang Y . Identification of Three (Iso)flavonoid Glucosyltransferases From . Front Plant Sci. 2019; 10:28. PMC: 6362427. DOI: 10.3389/fpls.2019.00028. View

16.

Frydman A, Weisshaus O, Bar-Peled M, Huhman D, Sumner L, Marin F . Citrus fruit bitter flavors: isolation and functional characterization of the gene Cm1,2RhaT encoding a 1,2 rhamnosyltransferase, a key enzyme in the biosynthesis of the bitter flavonoids of citrus. Plant J. 2004; 40(1):88-100. DOI: 10.1111/j.1365-313X.2004.02193.x. View

17.

Wang X, Xu Y, Zhang S, Cao L, Huang Y, Cheng J . Genomic analyses of primitive, wild and cultivated citrus provide insights into asexual reproduction. Nat Genet. 2017; 49(5):765-772. DOI: 10.1038/ng.3839. View

18.

Alseekh S, de Souza L, Benina M, Fernie A . The style and substance of plant flavonoid decoration; towards defining both structure and function. Phytochemistry. 2020; 174:112347. DOI: 10.1016/j.phytochem.2020.112347. View

19.

Li W, Li G, Yuan Z, Li M, Deng X, Tan M . Illustration of the variation in the content of flavanone rutinosides in various citrus germplasms from genetic and enzymatic perspectives. Hortic Res. 2022; 9. PMC: 8788359. DOI: 10.1093/hr/uhab017. View

20.

Kubo A, Arai Y, Nagashima S, Yoshikawa T . Alteration of sugar donor specificities of plant glycosyltransferases by a single point mutation. Arch Biochem Biophys. 2004; 429(2):198-203. DOI: 10.1016/j.abb.2004.06.021. View