The gradual establishment of complex coumarin biosynthetic pathway in Apiaceae

Telomere-to-telomere genome assembly reveals insights into the adaptive evolution of herbivore-defense mediated by volatile terpenoids in Oenanthe javanica

Releasing large quantities of volatiles is a defense strategy used by plants to resist herbivore attack. Oenanthe javanica, a perennial herb of the Apiaceae family, has a distinctive aroma due to volatile terpenoid accumulation. At present, the complete genome and genetic characteristics of volatile terpenoids in O. javanica remain largely unclear. Here, the telomere-to-telomere genome of O. javanica, with a size of 1012.13 Mb and a contig N50 of 49.55 Mb, was established by combining multiple sequencing technologies. Comparative genome analysis revealed that O. javanica experienced a recent species-specific whole-genome duplication event during the evolutionary process. Numerous gene family expansions were significantly enriched in the terpenoid biosynthesis process, monoterpenoid, and diterpenoid biosynthesis pathways, which resulted in abundant volatile substance accumulation in O. javanica. The volatile terpenoids of O. javanica showed repellent effects on herbivores. Terpenoid biosynthesis was activated by wounding signals under exogenous stimuli. The TPS gene family was significantly expanded in O. javanica compared to those in other species, and the members (OjTPS1, OjTPS3, OjTPS4, OjTPS5, OjTPS7, OjTPS16, OjTPS18, OjTPS30 and OjTPS58) responsible for different terpenoid biosynthesis were functionally characterized. These results reveal the genome evolution and molecular characteristics of volatile terpenoids in the process of plant-herbivore interactions. This study also provides genomic resources for genetic and molecular biology research on O. javanica and other plants.

Integrative multi-omics data provide insights into the biosynthesis of furanocoumarins and mechanisms regulating their accumulation in Angelica dahurica

Furocoumarins (FCs), important natural compounds with biodefense roles and pharmacological activities, are notably abundant in medicinal plant Angelica dahurica. However, its accumulation patterns over development stages in FC-enriched tissue, biosynthetic pathways, and regulatory mechanisms in A. dahurica remain elusive. Here, we quantified the concentration dynamics of 17 coumarins across six developmental stages of root and found a gradual decrease in FC concentration as the roots develop. Using a de-novo assembled chromosome-level genome for A. dahurica, we conducted integrative multi-omics analyses to screen out candidate genes to fill in the sole missing step in the biosynthesis of imperatorin and isoimperatorin. This revealed that CYP71AZ18 catalyzes hydroxylation at the C-5 position of psoralen to generate bergaptol, while CYP71AZ19 and CYP83F95 catalyze hydroxylation at the C-8 position to produce xanthotoxol, notably indicating that a single step is catalyzed by two genes from distinct CYP450 subfamilies in this species. CYP71AZ19 originated from a proximal duplication event of CYP71AZ18, specific to A. dahurica, and subsequently underwent neofunctionalization. Accessible chromatin regions (ACRs), especially proximal ACRs, correlated with high gene expression levels, and the three validated genes exhibited strong signals of ACRs, showing the importance of chromosomal accessibility in regulating metabolite biosynthesis.

A long road ahead to reliable and complete medicinal plant genomes

Long-read DNA sequencing has propelled medicinal plant genomics forward, with over 400 genomes from 203 plants sequenced by February 2025. However, many genomes still have assembly and annotation flaws, with only 11 gapless telomere-to-telomere assemblies. The core challenge remains identifying genes linked to secondary metabolite biosynthesis, regulation and evolution. High-quality complete genomes are essential for characterizing biosynthetic gene clusters and for enabling robust functional genomics and synthetic biology applications. We propose to focus on achieving more complete genome assemblies in diverse varieties on the basis of refining the currently available ones, leverage lessons from crop genomics research, and apply the cutting-edge genomics technologies in research of medicinal plant genomics.

Comparative Analysis of Metabolites of Wild and Cultivated Notopterygium incisum from Different Origins and Evaluation of Their Anti-Inflammatory Activity

The dried rhizome of Notopterygium incisum (NI) from the Umbelliferae family, genuinely produced in Sichuan, China, is a classic traditional Chinese medicinal herb for treating wind-dampness arthralgia. Due to scarce natural resources, wild NI is gradually being replaced by cultivated types. However, knowledge is limited regarding the differences in chemical composition and pharmacological effects between wild and cultivated NI and between Sichuan-grown and other-region-grown NI. In this study, a plant metabolomics strategy, based on GC-MS and UHPLC-Orbitrap MS, was employed to compare metabolic profiles between wild and cultivated NI and between cultivated NI from Sichuan and cultivated NI from Gansu and Qinghai. In total, 195 metabolites were identified, and the biosynthetic pathways of coumarins and phenolic acids, which were the most abundant secondary metabolites in NI, were summarized. Additionally, seven key metabolic intermediates were uncovered, revealing the reasons for the differences in metabolic profiles between wild and cultivated NI. The anti-inflammatory effect of wild and cultivated NI was verified by inflammatory gene expression and neutrophil count using a zebrafish yolk sac inflammation model. Overall, this study presents information on the types and synthesis of pharmacodynamic substances in NI and provides a basis for its cultivation and applications.

Deciphering the biosynthetic pathway of triterpene saponins in Prunella vulgaris

The traditional Chinese medicinal plant Prunella vulgaris contains numerous triterpene saponin metabolites, notably ursolic and oleanolic acid saponins, which have significant pharmacological values. Despite their importance, the genes responsible for synthesizing these triterpene saponins in P. vulgaris remain unidentified. This study used a comprehensive screening methodology, combining phylogenetic analysis, gene expression assessment, metabolome-transcriptome correlation and co-expression analysis, to identify candidate genes involved in triterpene saponins biosynthesis. Nine candidate genes - two OSCs, three CYP716s and four UGT73s - were precisely identified from large gene families comprising hundreds of members. These genes were subjected to heterologous expression and functional characterization, with enzymatic activity assays confirming their roles in the biosynthetic pathway, aligning with bioinformatics predictions. Analysis revealed that these genes originated from a whole-genome duplication (WGD) event in P. vulgaris, highlighting the potential importance of WGD for plant metabolism. This study addresses the knowledge gap in the biosynthesis of triterpene saponins in P. vulgaris, establishing a theoretical foundation for industrial production via synthetic biology. Additionally, we present an efficient methodological protocol that integrates evolutionary principles and bioinformatics techniques in metabolite biosynthesis research. This approach holds significant value for studies focused on unraveling various biosynthetic pathways.

Investigation of the anti-Huanglongbing effects using antimicrobial lipopeptide and phytohormone complex powder prepared from Bacillus amyloliquefaciens MG-2 fermentation

Global citrus production has been severely affected by citrus Huanglongbing (HLB) disease, caused by Candidatus Liberibacter asiaticus (Clas), and the development of effective control methods are crucial. This study employed antimicrobial lipopeptide and phytohormone complex powder (L1) prepared from the fermentation broth of the endophytic plant growth promoting bacterium (PGPB) of Bacillus amyloliquefaciens strain MG-2 to treat Candidatus Liberibacter asiaticus (CLas)-infected 'Citrus reticulata 'Chun Jian' plants. Real-time fluorescence quantitative polymerase chain reaction (qPCR) and PCR were employed for disease detection. The results revealed that after 15 spray-drench treatments with L1 solution, the HLB infection rate decreased from 100 to 50%, the bacterial titer decreased by 51.9% compared with a 27.9% decrease in the control group. L1 treatment triggered the production of reactive oxygen species, increased lignin content, and increased defense enzyme activities (p < 0.05). Defense-related gene expression significantly increased within 12 h of treatment. In addition, L1 application also promoted plant growth, as evidenced by higher transpiration rates and net photosynthetic rates as well as increased leave or root density. Root flora analysis revealed that the abundances of Burkholderia_thailandensis, unclassified_g_Burkholderia-Caballeronia-Paraburkholderia, unclassified_g__Allorhizobium-Neorhizobium-Pararhizobium-Rhizobium, and Pseudomonas_mosselii were 1.64, 1.46, 5.84, and 6.93 times greater, respectively, than those in the control group. The levels of phenylpropanoids, polyketides, lipids, lipid-like molecules, organic acids, and derivatives, significantly increased following L1 treatment (FC > 2, p < 0.05). Additionally, salicylic acid, dihydrojasmonic acid, and isopentenyl adenosine levels in leaves markedly increased. High-performance liquid chromatography (HPLC) confirmed that L1 contained surfactin, iturin and fengycin cyclic-lipopeptides (CLPs) as well as indole-3-acetic acid (IAA), 3-indolebutyric acid (IBA), indole-3-carboxylic acid and indole-3-carboxaldehyde auxins, N6-entopentenyladenine and t-zeatin-riboside cytokinins, abscisic acid, 1-aminocyclicpanecarboxylic acid, salicylic acid, and gibberellin A1, A3 and A4 phytohormones. These findings provide insight into multiple mechanisms by which endophytic Bacillus PGPB L1 is able to combat HLB disease, to promote citrus plant growth, and to optimize the root flora for soil health which offering an innovative strategy for sustainable management of this severe disease and improving citrus plant growth and productivity.

Proteomics: An Essential Tool to Study Plant-Specialized Metabolism

Plants are a valuable source of specialized metabolites that provide a plethora of therapeutic applications. They are natural defenses that plants use to adapt and respond to their changing environment. Decoding their biosynthetic pathways and understanding how specialized plant metabolites (SPMs) respond to biotic or abiotic stress will provide vital knowledge for plant biology research and its application for the future sustainable production of many SPMs of interest. Here, we focus on the proteomic approaches and strategies that help with the study of plant-specialized metabolism, including the: (i) discovery of key enzymes and the clarification of their biosynthetic pathways; (ii) study of the interconnection of both primary (providers of carbon and energy for SPM production) and specialized (secondary) metabolism; (iii) study of plant responses to biotic and abiotic stress; (iv) study of the regulatory mechanisms that direct their biosynthetic pathways. Proteomics, as exemplified in this review by the many studies performed to date, is a powerful tool that forms part of omics-driven research. The proteomes analysis provides an additional unique level of information, which is absent from any other omics studies. Thus, an integrative analysis, considered versus a single omics analysis, moves us more closely toward a closer interpretation of real cellular processes. Finally, this work highlights advanced proteomic technologies with immediate applications in the field.