Genome-Wide Analysis of the UGT Gene Family and Identification of Flavonoids in Broussonetia papyrifera

Genome-wide study of UDP-glycosyltransferases gene family in Cannabis sativa

The research focused on analyzing the UGT gene family in Cannabis sativa, which plays a crucial role in the plant's metabolism and glycosylation of secondary metabolites. The study identified 125 UGTs using conserved plant secondary product glycosyltransferase (PSPG) motif amino acid sequences. These UGT genes were categorized into 17 groups (A-Q) through phylogenetic analysis, showing their distribution across 10 chromosomes in C. sativa. The expansion of the CsUGT gene family was attributed to tandem and duplication events, as suggested by gene duplication analysis. Furthermore, the study found various cis-acting regulatory elements related to phytohormones and stress responses in CsUGT promoter regions. Subcellular localization analysis revealed that CsUGT is present in the cytoplasm, chloroplast, and nucleus. The study revealed that CsUGT plays a significant role in various biological processes, cellular components, and molecular functions as highlighted by Gene Ontology analysis. Additionally, the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that some CsUGTs are associated with the biosynthesis of secondary metabolites. This research provides valuable insights into the genomic organization, evolutionary history, and potential regulatory mechanisms of UGT genes in C. sativa. It lays the foundation for further exploration of their specific biological roles and potential applications in the plant's metabolism and stress responses. These findings contribute to a better understanding of the UGT gene family and its relevance to the metabolic pathways in C. sativa.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-04025-3.

Integrated transcriptomic and WGCNA analyses reveal candidate genes regulating mainly flavonoid biosynthesis in Litsea coreana var. sinensis

Litsea coreana Levl. var. sinensis (Allen) Yang et P. H. Huang is a popular ethnic herb and beverage plant known for its high flavonoid content, which has been linked to a variety of pharmacological benefits and crucial health-promoting impacts in humans. The progress in understanding the molecular mechanisms of flavonoid accumulation in this plant has been hindered due to the deficiency of genomic and transcriptomic resources. We utilized a combination of Illumina and Oxford Nanopore Technology (ONT) sequencing to generate a de novo hybrid transcriptome assembly. In total, 126,977 unigenes were characterized, out of which 107,977 were successfully annotated in seven public databases. Within the annotated unigenes, 3,781 were categorized into 58 transcription factor families. Furthermore, we investigated the presence of four valuable flavonoids-quercetin-3-O-β-D-galactoside, quercetin-3-O-β-D-glucoside, kaempferol-3-O-β-D-galactoside, and kaempferol-3-O-β-D-glucoside in 98 samples, using high-performance liquid chromatography. A weighted gene co-expression network analysis identified two co-expression modules, MEpink and MEturquoise, that showed strong positive correlation with flavonoid content. Within these modules, four transcription factor genes (R2R3-MYB, NAC, WD40, and ARF) and four key enzyme-encoding genes (CHI, F3H, PAL, and C4H) emerged as potential hub genes. Among them, the R2R3-MYB (LcsMYB123) as a homologous gene to AtMYB123/TT2, was speculated to play a significant role in flavonol biosynthesis based on phylogenetic analysis. Our findings provided a theoretical foundation for further research into the molecular mechanisms of flavonoid biosynthesis. Additionally, The hybrid transcriptome sequences will serve as a valuable molecular resource for the transcriptional annotation of L. coreana var. sinensis, which will contribute to the improvement of high-flavonoid materials.

Transcriptome analysis provides insights into coumarin biosynthesis in the medicinal plant Angelica dahurica cv. Yubaizhi

Angelica dahurica roots have a long history of use in traditional Chinese medicine due to their high coumarin content. To address the increasing demand for these roots, a synthetic biology approach has been proposed. Nevertheless, our comprehension of coumarin biosynthesis and its regulation remains limited. In this study, we utilized Hiseq2500 sequencing to analyze the transcriptomes of A. dahurica at different growth stages while concurrently quantifying coumarin content. Differentially expressed gene (DEG) analysis was employed to identify key genes involved in coumarin and terpenoid backbone biosynthesis. Weighted gene co-expression network analysis (WGCNA) was applied to identify gene modules strongly associated with coumarin content, elucidating the regulatory relationships between transcription factors (TFs) and pathway genes. Furthermore, KEGG enrichment analysis was used to explore essential pathways governing coumarin biosynthesis, with the identification of hub genes. Our results indicated that total coumarin content was highest in the roots, followed by leaves and stems, across all three developmental stages. Transcriptome analysis identified a total of 92,478 genes, among which 215 and 30 genes were implicated in coumarin and terpenoid backbone biosynthesis, respectively. Within the 73 identified gene modules by WGCNA, three modules-namely aquamarine1 (comprising two OMTs, one CSE, one AACT, one HDS, two PSs, one 2OGO, four UGTs, and seven CYP450s), darkmagenta (containing one UGT and one HDR), and navajowhite2 (consisting of one HCT, three UGTs, one CYP71A25, one OMT, one CSE, one HDS, and one PT)-were strongly associated with imperatorin, oxypeucedanin, and isoimperatorin content, respectively. KEGG enrichment analysis highlighted significant enrichment of cytochrome P450, transporter, and ubiquitin system pathways. Moreover, TF-gene regulatory analysis unveiled the complexity of coumarin biosynthesis, with 17 TF families regulating 17 genes in the aquamarine1 module, 8 TF families regulating 2 genes in the darkmagenta module, and 8 TF families regulating 7 genes in the navajowhite2 module. These comprehensive findings provide valuable insights into coumarin biosynthesis in A. dahurica, facilitating future research and potential applications in traditional Chinese medicine and synthetic biology strategies.

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

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.

Genome-wide analysis of UDP-glycosyltransferase gene family and identification of members involved in flavonoid glucosylation in Chinese bayberry (Morella rubra)

Glycosylation was catalyzed by UDP-glycosyltransferase (UGT) and was important for enriching diversity of flavonoids. Chinese bayberry (Morella rubra) has significant nutritional and medical values because of diverse natural flavonoid glycosides. However, information of UGT gene family was quite limited in M. rubra. In the present study, a total of 152 MrUGT genes clustered into 13 groups were identified in M. rubra genome. Among them, 139 MrUGT genes were marked on eight chromosomes and 13 members located on unmapped scaffolds. Gene duplication analysis indicated that expansion of MrUGT gene family was mainly forced by tandem and proximal duplication events. Gene expression patterns in different tissues and under UV-B treatment were analyzed by transcriptome. Cyanidin 3-O-glucoside (C3Glc) and quercetin 3-O-glucoside (Q3Glc) were two main flavonoid glucosides accumulated in M. rubra. UV-B treatment significantly induced C3Glc and Q3Glc accumulation in fruit. Based on comprehensively analysis of transcriptomic data and phylogenetic homology together with flavonoid accumulation patterns, MrUFGT (MrUGT78A26) and MrUGT72B67 were identified as UDP-glucosyltransferases. MrUFGT was mainly involved in C3Glc and Q3Glc accumulation in fruit, while MrUGT72B67 was mainly involved in Q3Glc accumulation in leaves and flowers. Gln375 and Gln391 were identified as important amino acids for glucosyl transfer activity of MrUFGT and MrUGT72B67 by site-directed mutagenesis, respectively. Transient expression in Nicotiana benthamiana tested the function of MrUFGT and MrUGT72B67 as glucosyltransferases. The present study provided valuable source for identification of functional UGTs involved in secondary metabolites biosynthesis in M. rubra.

The Genus Broussonetia: An Updated Review of Phytochemistry, Pharmacology and Applications

The Broussonetia genus (Moraceae), recognized for its value in many Chinese traditional herbs, mainly includes Broussonetia papyrifera (L.) L’Hér. ex Vent. (BP), Broussonetia kazinoki Siebold (BK), and Broussonetia luzonica (Blanco) Bureau (BL). Hitherto, researchers have found 338 compounds isolated from BP, BK, and BL, which included flavonoids, polyphenols, phenylpropanoids, alkaloids, terpenoids, steroids, and others. Moreover, its active compounds and extracts have exhibited a variety of pharmacological effects such as antitumor, antioxidant, anti-inflammatory, antidiabetic, anti-obesity, antibacterial, and antiviral properties, and its use against skin wrinkles. In this review, the phytochemistry and pharmacology of Broussonetia are updated systematically, after its applications are first summarized. In addition, this review also discusses the limitations of investigations and the potential direction of Broussonetia. This review can help to further understand the phytochemistry, pharmacology, and other applications of Broussonetia, which paves the way for future research.

Genome-Wide Analysis and Profile of UDP-Glycosyltransferases Family in Alfalfa (Medicago sativa L.) under Drought Stress

Drought stress is one of the major constraints that decreases global crop productivity. Alfalfa, planted mainly in arid and semi-arid areas, is of crucial importance in sustaining the agricultural system. The family 1 UDP-glycosyltransferases (UGT) is indispensable because it takes part in the regulation of plant growth and stress resistance. However, a comprehensive insight into the participation of the UGT family in adaptation of alfalfa to drought environments is lacking. In the present study, a genome-wide analysis and profiling of the UGT in alfalfa were carried out. A total of 409 UGT genes in alfalfa (MsUGT) were identified and they are clustered into 13 groups. The expression pattern of MsUGT genes were analyzed by RNA-seq data in six tissues and under different stresses. The quantitative real-time PCR verification genes suggested the distinct role of the MsUGT genes under different drought stresses and abscisic acid (ABA) treatment. Furthermore, the function of MsUGT003 and MsUGT024, which were upregulated under drought stress and ABA treatment, were characterized by heterologous expression in yeast. Taken together, this study comprehensively analyzed the UGT gene family in alfalfa for the first time and provided useful information for improving drought tolerance and in molecular breeding of alfalfa.

Exploring the SiCCT Gene Family and Its Role in Heading Date in Foxtail Millet

CCT transcription factors are involved in the regulation of photoperiod and abiotic stress in Arabidopsis and rice. It is not clear that how CCT gene family expand and regulate heading date in foxtail millet. In this study, we conducted a systematic analysis of the CCT gene family in foxtail millet. Thirty-nine CCT genes were identified and divided into four subfamilies based on functional motifs. Analysis showed that dispersed duplication played a predominant role in the expansion of CCT genes during evolution. Nucleotide diversity analysis suggested that genes in CONSTANS (COL)-like, CCT MOTIF FAMILY (CMF)-like, and pseudoresponse response regulator (PRR)-like subfamilies were subjected to selection. Fifteen CCT genes were colocalized with previous heading date quantitative trait loci (QTL) and genome-wide association analysis (GWAS) signals. Transgenic plants were then employed to confirm that overexpression of the CCT gene SiPRR37 delayed the heading date and increased plant height. Our study first investigated the characterization and expansion of the CCT family in foxtail millet and demonstrated the role of SiPRR37. These results lay a significant foundation for further research on the function of CCT genes and provide a cue for the regulation of heading date.

iTRAQ-Based Quantitative Proteomics Analysis Reveals the Mechanism of Golden-Yellow Leaf Mutant in Hybrid Paper Mulberry

Plant growth and development relies on the conversion of light energy into chemical energy, which takes place in the leaves. Chlorophyll mutant variations are important for studying certain physiological processes, including chlorophyll metabolism, chloroplast biogenesis, and photosynthesis. To uncover the mechanisms of the golden-yellow phenotype of the hybrid paper mulberry plant, this study used physiological, cytological, and iTRAQ-based proteomic analyses to compare the green and golden-yellow leaves of hybrid paper mulberry. Physiological results showed that the mutants of hybrid paper mulberry showed golden-yellow leaves, reduced chlorophyll, and carotenoid content, and increased flavonoid content compared with wild-type plants. Cytological observations revealed defective chloroplasts in the mesophyll cells of the mutants. Results demonstrated that 4766 proteins were identified from the hybrid paper mulberry leaves, of which 168 proteins displayed differential accumulations between the green and mutant leaves. The differentially accumulated proteins were primarily involved in chlorophyll synthesis, carotenoid metabolism, and photosynthesis. In addition, differentially accumulated proteins are associated with ribosome pathways and could enable plants to adapt to environmental conditions by regulating the proteome to reduce the impact of chlorophyll reduction on growth and survival. Altogether, this study provides a better understanding of the formation mechanism of the golden-yellow leaf phenotype by combining proteomic approaches.

Genome-Wide Analysis of the UDP-Glycosyltransferase Family Reveals Its Roles in Coumarin Biosynthesis and Abiotic Stress in Melilotus albus

Coumarins, natural products abundant in Melilotus albus, confer features in response to abiotic stresses, and are mainly present as glycoconjugates. UGTs (UDP-glycosyltransferases) are responsible for glycosylation modification of coumarins. However, information regarding the relationship between coumarin biosynthesis and stress-responsive UGTs remains limited. Here, a total of 189 MaUGT genes were identified from the M. albus genome, which were distributed differentially among its eight chromosomes. According to the phylogenetic relationship, MaUGTs can be classified into 13 major groups. Sixteen MaUGT genes were differentially expressed between genotypes of Ma46 (low coumarin content) and Ma49 (high coumarin content), suggesting that these genes are likely involved in coumarin biosynthesis. About 73.55% and 66.67% of the MaUGT genes were differentially expressed under ABA or abiotic stress in the shoots and roots, respectively. Furthermore, the functions of MaUGT68 and MaUGT186, which were upregulated under stress and potentially involved in coumarin glycosylation, were characterized by heterologous expression in yeast and Escherichia coli. These results extend our knowledge of the UGT gene family along with MaUGT gene functions, and provide valuable findings for future studies on developmental regulation and comprehensive data on UGT genes in M. albus.