Genome-wide identification, characterization, and expression analysis of UDP-glycosyltransferase genes associated with secondary metabolism in alfalfa (Medicago sativa L.)

Abstract

Uridine diphosphate glycosyltransferases (UGTs) are enzymes that catalyze glycosylation modifications and play an essential role in regulating plant metabolism. Alfalfa (Medicago sativa L.) is the most important legume in the world due to its high yields and protein content; however, the UGT genes in alfalfa have not yet been studied. Identifying UGT genes with metabolic roles in alfalfa is essential for identifying and modifying genetic traits that are relevant to yield and quality. In this study, 90 of the 239 UGT genes identified from the alfalfa “Zhongmu No. 1” genome database were found to be related to secondary metabolism, and a series of gene family characterization analyses were conducted on each. The results demonstrated that all 90 UGT genes were unevenly distributed on eight chromosomes with few introns and that tandem duplications were the crucial driving force expanding the UGT family in alfalfa. Notably, the 90 UGT genes can be clustered into ten evolutionary groups which contain specific PSPG motifs, and genes in these ten groups have specific tissue expressions. This suggests that the UGT genes in each group could have similar glycosylation roles corresponding to analogous secondary metabolites in alfalfa. Additionally, multiple cis-acting elements found in MsUGT promoter regions, such as phytohormone and flavonoids, indicate that 90 UGT members could be induced by these features, which are also related to secondary metabolism. Therefore, our study identified 90 UGT members inten evolutionary groups that are likely related to glycosylation modifications with secondary metabolites in alfalfa. These findings help uncover pivotal regulatory mechanisms associated with secondary metabolism in plant yield and quality and contribute to genetic modification and breeding in alfalfa and other plant species.

Elucidation of the Biosynthesis of Asiaticoside and Its Reconstitution in Yeast

“…With the development of high-throughput sequencing technology, plant transcriptomes are being studied more and more extensively, facilitating the mining of biosynthetic pathways of many high-value plant natural products. , Currently, transcriptome sequencing technology combined with bioinformatics analysis is an effective means to mine UGTs. − de Costa et al and Kim et al identified glycosyltransferases Ca UGT73AD1 and Ca UGT73AH1 mediating glycosylation of asiatic acid from the C. asiatica transcriptome, but the UGTs that ultimately generate asiaticoside and madecassoside need to be further investigated. , Asiaticoside and madecassoside share the same sugar chain (glucose–glucose–rhamnose) linking their carboxyl groups .…”

Glycosylation of Secondary Metabolites: A Multifunctional UDP-Glycosyltransferase, CsUGT74Y1, Promotes the Growth of Plants

“…For example, in grapevines, UGT 85 A 24 and UGT 85 A 25 are expressed in berries and influence their flavor, whereas UGT 85 A 26 and UGT 85 A 27 are predominantly expressed in leaves and enhance plant defense against herbivores and pathogens . In Medicago sativa, UGT 28, UGT 54, and UGT 79 are highly expressed in leaves, potentially due to the increased accumulation of flavonoids and terpenoids . Our previous study revealed that CsUGT 75 L 12 and CsUGT 79 B 28 are expressed in the tender tissues of tea plants, and the enzymes encoded by these genes catalyze the biosynthesis of bitter flavonoid 7- O -neohesperidosides .…”

“…33 In Medicago sativa, UGT28, UGT54, and UGT79 are highly expressed in leaves, potentially due to the increased accumulation of flavonoids and terpenoids. 34 Our previous study revealed that CsUGT75L12 and CsUGT79B28 are expressed in the tender tissues of tea plants, and the enzymes encoded by these genes catalyze the biosynthesis of bitter flavonoid 7-O-neohesperidosides. 24 The relative expression analysis conducted in this study revealed that 32.14% of all CsUGT genes were expressed in the tender shoots of C. sinensis (Figure 3a), whereas 35% were expressed in C. sinensis var.…”

Identification and Functional Verification of the Glycosyltransferase Gene Family Involved in Flavonoid Synthesis in Rubus chingii Hu

“…The UGT genes of four Rubus species were unevenly distributed among groups, and there were great differences among species. The groups L and O had the most members in R. chingii (31 and 32), and group L also occupied most members in R. idaeus (26) and R. occidentalis (17), respectively, and group E in R. corchorifolius (24) had the most members. Furthermore, compared with the other three Rubus plants UGTs, the RchUGTs and RchUGTs lacked group G and N, respectively.…”

“…The UGTs of plants not only participate in the synthesis of plant secondary metabolites, but also have a variety of biological functions, such as a role in plant antitoxin and defense mechanisms, the response to abiotic stress, and in the regulation of plant hormones [13,16,17]. UGT genes have been identified in many plants, including Arabidopsis thaliana (121) [9], Populus trichocarpa (191) [18], wheat (179) [19], Gossypium raimondii (142) [20], Quercus robur (244) [21], apple (299) [22], Morella rubra (152) [23], alfalfa (90) [24], and so on. Up to now, there have been few studies on the UGT family of R. chingii, only mentioned in the publication of the Chinese raspberry genome [2], and the number of identified UGT genes may be incomplete.…”