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At least 19 recordsLinked to original sources
PubMed2026

Evolving conservation: The role of unconventional approaches to restore contemporary vertebrate populations and genomic biodiversity.

Conservation biology and restoration ecology are two essential yet distinct disciplines that address the growing challenge of biodiversity loss. Traditionally, these fields have relied on ecological principles and management practices aimed at protecting or reestablishing natural systems. The crisis is no longer just ecological; it is evolutionary and genomic. The accelerating pace of environmental change has outstripped the capacity of conventional approaches, creating a pressing need for innovative solutions. Biotechnology offers potentially transformative tools that can enhance the effectiveness and precision of both conservation and restoration efforts, especially for species where conventional conservation approaches have proved insufficient. Techniques such as genetic rescue, synthetic biology, and gene editing are increasingly being explored to address critical challenges, such as invasive species control, genetic diversity loss, and habitat fragmentation, to both invigorate endangered species and restore historical biodiversity. Despite its promise, the integration of biotechnology into conservation and restoration has raised ethical, ecological, and regulatory concerns. These include ecological unpredictability and public resistance to genetic interventions in wild populations. This perspective examines the current landscape of biotechnological applications in conservation and restoration, highlighting successful case studies, ongoing controversies, and optimism for additional progress. We argue that thoughtful, transparent integration of biotechnology that is grounded in ecological knowledge and stakeholder engagement can reconcile the goals of conservation and restoration. As ecosystems face mounting pressures, biotech-enabled strategies may prove essential for fostering resilience and ensuring long-term ecological sustainability.

Conservation of Natural Resources↗
PubMed2026

Population and landscape genomics provide insights into the adaptive genetic variation and future climate-induced vulnerability of the endangered tree species Phoebe bournei.

Elucidating the genomic underpinnings of adaptive variation is highly important for the conservation, landscape application, and management of ornamental trees against the backdrop of global climate change. However, research on the genetic mechanisms underlying climate adaptation in Phoebe bournei-a near-threatened subtropical tree species endemic to China, which is endowed with exceptionally high ornamental and ecological value-remains scarce. Whole-genome resequencing was conducted on 362 individuals from 27 natural populations across the geographical range of the species. Genome-environment association analyses were employed to identify 1556 climate-associated variants and 167 candidate genes associated with temperature and precipitation variables. Through functional annotation and expression profiling, pivotal genes, including TRX-M4 and FBD1, were identified as integral to drought and heat stress responses, with adaptive alleles displaying distinct geographic frequency distributions and significant phenotypic differentiation. Divergent evolutionary trajectories were deduced among populations, with southeastern populations distinguished by elevated genetic diversity and strong signatures of local adaptation. Nevertheless, projections derived from the Risk of Non-Adaptedness and gradient forest models suggest that these southeastern populations will face substantial genomic offset under future climate scenarios, signaling heightened vulnerability and the need for prioritized conservation and management. This study provides the first genome-wide perspective into the adaptive evolution of P. bournei and offers a robust foundation for its conservation and climate-resilient management.

Journal Article↗
PubMed2025

The plastid genome of the critically endangered Valeriana trinervis (= Centranthus trinervis) and insights from comparison with other Valeriana plastomes (Caprifoliaceae).

The first complete plastid genome of the critically endangered species Valeriana trinervis was sequenced, assembled and compared with other published Valeriana plastomes. In this study, we assembled the plastid genome of the critically endangered, endemic species Valeriana trinervis (= Centranthus trinervis) and compare it with all published plastomes of Valeriana. We found not only differences in the inverted repeats boundaries, in the type and abundance of repeats, but also similarities in codon usage and microsatellite numbers. We detected non-canonical start codons in several genes and identified variation in several regions that could be useful for phylogenetic and phylogeographic studies. The phylogenetic tree inference based on both full plastomes and coding sequence data indicated that V. trinervis is sister to all Eurasian Valeriana accessions confirming the phylogenetic position recently investigated. This is the first plastome available for a species of the Mediterranean clade of Valeriana previously known as Centranthus, and it adds further data to understand the evolution and diversification of this systematically debated genus.

Genome, Plastid↗
PubMed2024

Next-generation phylogeography reveals unanticipated population history and climate and human impacts on the endangered floodplain bitterling (Acheilognathus longipinnis).

BACKGROUND: Floodplains harbor highly biodiverse ecosystems, which have been strongly affected by both past climate change and by recent human activities, resulting in a high prevalence of many endangered species in these habitats. Understanding the history of floodplain species over a wide range of timescales can contribute to effective conservation planning. We reconstructed the population formation history of the Itasenpara bitterling Acheilognathus longipinnis, an endangered floodplain fish species in Japan, over a broad timescale based on phylogenetic analysis, demographic modeling, and historical demographic analysis using mitogenome and whole-genome sequences. A genome sequence was newly assembled as a reference for the resequencing analysis. This bitterling is distributed in three plains separated by high mountain ranges and exhibits ecological characteristics well adapted to floodplain environments. RESULTS: Our analyses revealed an unexpected population branching pattern, gene flow, and timing of the differentiation that occurred within a few hundred thousand years, i.e., long after the mountain uplift that was assumed to be the primary geological cause of the population differentiation. The analyses also showed that all local populations experienced a severe decline during the last glacial and post-glacial periods. CONCLUSIONS: Our results suggest that the floodplain bitterling was able to disperse through unknown routes after mountain uplift and that its populations were strongly influenced by climatic and geographic changes in glacial-interglacial cycles and subsequent human activities, probably related to its floodplain-dependent ecology. The genomic data highlight the unanticipated distribution process of this species and the magnitude of the impact of human activities, with important implications for its conservation.

Endangered Species↗
PubMed2026

Genomic Tracking of Market-Derived Bull Shark Fins Back to Source Population of Origin.

International trade of shark fins remains difficult to monitor because products are rarely labelled to species and are often highly processed, resulting in severely degraded DNA. For several shark species listed under Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), this limits external verification of source populations supplying global trade hubs. Here, we assess whether nuclear genomic approaches can be applied to market-derived bull shark (Carcharhinus leucas) fins to determine their population of origin. We analysed dried fin trimmings collected from retail vendors in Hong Kong SAR, one of the world's largest dried shark fin trade hubs, using a targeted DArTcap single nucleotide polymorphism (SNP) panel, originally developed for population genomic studies of this species. Despite substantial DNA degradation, genomic libraries were successfully obtained for most samples, yielding sufficient SNP data to perform robust provenance and sex assignment. Using a Bayesian mixed-stock analysis, most fin samples were assigned to the Indo-West Pacific (71.4%), with smaller contributions from the western Atlantic (22.6%) and eastern Pacific (3.0%). Genetic sex assignment revealed twice as many males as females, although results indicated a conservative bias towards male assignment due to the limited number of X-linked markers available in degraded samples. Our results demonstrate that genome-wide targeted approaches can be effectively applied to highly processed shark fin products to infer population sources and sex composition. This study provides proof-of-concept for integrating genomics into shark trade monitoring, highlighting its potential to improve traceability, support CITES implementation and inform conservation and fisheries management, particularly for species with well-resolved population structure.

Animals↗
PubMed2026

Ex situ reared black-footed ferrets exhibit altered sperm DNA methylation.

Many endangered species rely on ex situ management for survival when external threats exist on the landscape. Yet, ex situ settings pose challenges through space limitation, altered environment, and diet. This can lead to environmentally determined inbreeding depression, where ex situ animals exhibit reduced reproductive fitness compared with their in situ counterparts, despite originating from the same genetic stock. We investigated epigenetic differences as a potential mechanism underlying environmentally determined inbreeding depression in black-footed ferrets (Mustela nigripes), a North American endemic species reliant on ex situ conservation. More specifically, we explored how environmental context may influence sperm DNA methylation in samples collected from 12 ex situ and 5 in situ males. Average sperm DNA methylation was significantly higher in ex situ individuals. We additionally identified more than 500 differentially methylated regions between ex situ and in situ sperm samples that were enriched for gene ontology terms pertaining to reproduction and development. Putative genes of interest included NPR2, WEE2, SLC15A1, PDE10A, PIP5K1B, CACNA1E, and CACNA1A, all of which have previously been linked to spermatogenesis, sperm motility, or fertilization in mammals. Results suggest that environmental conditions may alter sperm DNA methylation in black-footed ferrets, with possible links to decreased reproductive success in ex situ settings. These findings provide valuable insights into the molecular mechanisms underlying environmentally determined inbreeding depression in black-footed ferrets and other conservation-reliant species, and can serve as a foundation for future research on improving reproductive health in endangered wildlife.

Animals↗
PubMed2024

Genetic linkage disequilibrium of deleterious mutations in threatened mammals.

The impact of negative selection against deleterious mutations in endangered species remains underexplored. Recent studies have measured mutation load by comparing the accumulation of deleterious mutations, however, this method is most effective when comparing within and between populations of phylogenetically closely related species. Here, we introduced new statistics, LDcor, and its standardized form nLDcor, which allows us to detect and compare global linkage disequilibrium of deleterious mutations across species using unphased genotypes. These statistics measure averaged pairwise standardized covariance and standardize mutation differences based on the standard deviation of alleles to reflect selection intensity. We then examined selection strength in the genomes of seven mammals. Tigers exhibited an over-dispersion of deleterious mutations, while gorillas, giant pandas, and golden snub-nosed monkeys displayed negative linkage disequilibrium. Furthermore, the distribution of deleterious mutations in threatened mammals did not reveal consistent trends. Our results indicate that these newly developed statistics could help us understand the genetic burden of threatened species.

Animals↗
PubMed2025

Time-lagged genomic erosion and future environmental risks in a bird on the brink of extinction.

Global biodiversity is rapidly declining due to habitat degradation and genomic erosion, highlighting the urgent need to monitor endangered species and their genetic health. Temporal genomics and ecological modelling offer finer resolution than single-time-point measurements, providing a comprehensive view of species' recent and future trajectories. We investigated genomic erosion and environmental suitability in the critically endangered regent honeyeater (Anthochaera phrygia) by sequencing whole genomes of historical and modern specimens and building multi-temporal species distribution models (SDMs) across the last century. The species has declined from hundreds of thousands of individuals to fewer than 300 over the past 100 years. SDMs correctly predicted known patterns of local extinction in southeast Australia. Our demographic reconstructions revealed a gradual population decline from 2000 to 2500 years ago, sharply accelerating in the last 500 years due to climate variability and habitat loss. Despite this substantial demographic collapse, the regent honeyeater has lost only 9% of its genetic diversity, with no evidence of inbreeding or connectivity loss. Also, it exhibits higher diversity than many other threatened bird species. Forward-in-time genomic simulations indicate that this time lag between population decline and genetic diversity loss conceals the risk of ongoing genomic erosion into a future of rapidly degrading environmental suitability. Our work underscores the need for targeted conservation efforts and continuous genetic monitoring to prevent species extinction.

Animals↗
PubMed2026

Rapid derivation of cloning-competent cells from peripheral blood advances conservation biobanking.

Establishing viable cell lines from endangered species is essential for conservation, yet traditional fibroblast derivation from skin biopsies faces challenges including contamination risk and extended culture timelines. Here, we demonstrate that endothelial progenitor cells (EPCs) and pericytes isolated from peripheral blood represent robust alternatives to fibroblasts for biobanking. Compared to canid fibroblasts, canid blood-derived cells exhibit 2- to 3-fold faster doubling rates (15 to 20 h vs. ~35 h for fibroblasts) and reduced time to banked cell lines (1.5 to 2 wks vs. 3 to 4 wks for fibroblasts). Proteomic profiling of 32 canonical markers confirmed EPCs and pericytes represent distinct populations with lineage-specific molecular signatures. Optical genome mapping demonstrated equivalent genomic stability across cell types with no detectable structural variants or aneuploidies. Finally, interspecific somatic cell nuclear transfer (iSCNT) experiments confirmed both EPCs and pericytes generate viable canid embryos with efficiency meeting or exceeding fibroblasts. As a proof of concept for conservation cloning, iSCNT embryos made with gray wolf blood-derived cells had a 15% implantation rate following embryo transfer and resulted in six viable fetuses. These findings support integrating blood-derived cell banking into conservation programs, which enables opportunistic genetic preservation during standard management activities and expands options for genetic rescue through assisted reproductive technologies.

Animals↗
PubMed2026

Past genomes guide future conservation: insights from extinct populations of the endangered Pacific pocket mouse.

Efforts to recover endangered species often rely on restoring populations to their historical range, yet reestablishing lost genetic variation is challenging when the ancestral genetic landscape is poorly understood. The Pacific pocket mouse (Perognathus longimembris pacificus), a federally endangered heteromyid rodent, has been extirpated from most of its range in coastal southern California. Recovery efforts call for establishing new populations in their historic range through translocation, but the extent to which historical patterns of genetic variation can be recapitulated is unknown. To inform conservation planning, we sequenced whole genomes of historical samples, including individuals from populations that went extinct in the mid-1900s. Phylogenetic analyses revealed that mice from the southernmost extirpated population form a clade with a different subspecies, while populations to the north form a sister clade. These findings support morphological evidence calling for a taxonomic revision, which would modify the definition of the historic range and complicate the interpretation of suitable reintroduction sites. Despite this divergence, D-statistics and demographic models indicate historical gene flow among coastal populations, suggesting that alleles reintroduced to the southern coast may echo ancestral connectivity. Thus, management efforts should consider potential receiver sites that contain suitable habitat within this range as viable for population creation. These results highlight the value of historical genomics in guiding conservation decisions, particularly when taxonomic uncertainty, extirpation, and limited genetic diversity constrain modern management. Although historical baselines often cannot be restored, conservation strategies can leverage genomic insights to enhance future adaptive potential and long-term resilience of threatened species.

Endangered Species↗
PubMed2025

Illuminating the mystery of thylacine extinction: a role for relaxed selection and gene loss.

Gene loss shapes lineage-specific traits but is often overlooked in species survival. In this study, we investigate the role of ancestral gene loss using the extinction icon-thylacine (Thylacinus cynocephalus). While studies of neutral genetic variation indicate a population decline before extinction, the impact of thylacine-specific ancestral gene losses remains unexplored. The availability of a chromosomal-level genome of the extinct thylacine offers a unique opportunity for such comparative studies. Here, we leverage palaeogenomic data to compare gene presence/absence patterns between the Tasmanian devil and thylacine. We discovered ancestral (between 13-1 Ma) loss of SAMD9L, HSD17B13, CUZD1 and VWA7 due to multiple gene-inactivating mutations, corroborated by short-read sequencing. The timing of gene loss mirrors the thylacine's shift towards hypercarnivory and increased body size. Notably, the loss of SAMD9 correlates with a carnivorous diet. Our genome-wide analysis reveals olfactory receptor loss and relaxed selection, aligning with reduced olfactory lobes in the thylacine, indicating olfaction is not its primary hunting sense. By integrating palaeogenomic data with comparative genomics, our study reveals ancestral gene losses and their impact on species survival and resilience to environmental changes. Our approach can be extended to other extinct and endangered species, helping to identify genetic factors for conservation efforts.

Animals↗
PubMed2026

Species distribution models predict genome-wide polymorphism and gene flow in an endangered amphibian.

Species distribution models (SDMs) are widely used to predict habitat suitability but their usefulness and accuracy for inferring population health is still debated. Here, we evaluate whether SDM-derived relative habitat suitability (RHS) predicts genome-wide genetic diversity and connectivity-which are key proxies for population health and the functional integrity of landscapes. We addressed this issue in the Yellow-bellied toad (Bombina variegata), an endangered amphibian species with limited dispersal. We combined hierarchical SDMs, integrating both continental-level bioclimatic data and regional-level landscape variables, with genome-wide SNP data from 404 individuals sampled across 92 sites in southeastern France. We then used a multi-scale modelling framework to test the effect of bioclimatic (BRHS) and landscape (LRHS) habitat suitability on observed heterozygosity and pairwise genetic differentiation, accounting for heterogeneous genetic drift using gravity models. Our results show that both BRHS and LRHS are significant predictors of heterozygosity, with their effects expressed at different spatial scales-11 km and 3 km for BRHS and LRHS, respectively. Connectivity patterns also widely varied depending on scale and were best explained by gravity models integrating LRHS, BRHS, and local heterozygosity, underscoring the combined role of landscape resistance and population size in shaping patterns of genetic differentiation. These findings show that SDMs, when carefully calibrated and interpreted, can provide proxies for genetic diversity and landscape resistance in species with limited dispersal.

Journal Article↗
PubMed2026

Resolving taxonomic complexity in the genus Boechera (Brassicaceae) using the Boechera Microsatellite Website: a case study of the rare triploid B. bodiensis.

BACKGROUND AND AIMS: The genus Boechera (rock cress) comprises ∼75 sexual diploid taxa and >355 genetically distinct hybrid lineages, many of which reproduce asexually through apomixis. This complex reproductive landscape poses substantial challenges for taxonomy, similar to those encountered in genera such as Taraxacum, Hieracium, Poa and Rubus. The Boechera Microsatellite Website (BMW) offers an extensive database and analytical tools that are proving instrumental in resolving these difficulties. Here, we demonstrate the utility of the BMW through analysis of Boechera bodiensis, a rare and poorly understood species endemic to the western Great Basin of the USA. METHODS: First described as Arabis bodiensis by Rollins in 1982, this taxon is sparsely represented in herbaria and has long been considered a candidate for protection under the Endangered Species Act. However, its taxonomic identity has remained uncertain owing to morphological similarities with other 'Arabis' (Boechera) taxa. We integrate microsatellite DNA data from the BMW with morphological analyses to provide a clearer understanding of the taxonomic status, distribution and evolutionary origins of B. bodiensis. KEY RESULTS: Pollen studies reveal that B. bodiensis is a diplosporous apomict. Microsatellite genotyping of the holotype confirms it to be triploid, containing three subgenomes derived from Boechera cobrensis, B. fernaldiana and B. sparsiflora. Expanded microsatellite surveys detect this triploid genotype at 22 additional sites, primarily in Mono County, CA, USA. Morphological analyses of genetically verified specimens identify a consistent set of characters that distinguish B. bodiensis from co-occurring congeners. CONCLUSIONS: The BMW enables high-resolution analyses of genome composition, reproductive mode and hybrid origins, making it a powerful tool for resolving taxonomic complexity in Boechera. Our case study of B. bodiensis highlights the effectiveness of combining molecular and morphological data to clarify species boundaries, inform conservation assessments and refine nomenclatural understanding in this notoriously difficult genus.

Microsatellite Repeats↗
PubMed2025

Genome Report: De novo genome assembly of the greater Bermuda land snail, Poecilozonites bermudensis (Mollusca: Gastropoda), confirms ancestral genome duplication.

Poecilozonites bermudensis, the greater Bermuda land snail, is a critically endangered species and one of only two extant members in its genus. These snails are one of Bermuda's few endemic animal clades and their rich fossil record was the basis for the punctuated equilibria model of speciation. Once thought extinct, recent conservation efforts have focused on the recovery of the species, yet no genomic information or other molecular sequences have been available to inform these initiatives. We present a high-quality, annotated genome for P. bermudensis generated using PacBio long read and Omni-C short read sequencing. The resulting assembly is approximately 1.36 Gb with a scaffold N50 of 44.t Mb and 31 chromosome-length scaffolds. Nearly 43 percent of the genome was identified as repeat content. This assembly will serve as a resource for the conservation and study of P. bermudensis, and its only close extant and also critically endangered relative, P. circumfirmatus. Additionally, this genome adds to the growing body of data needed for a more complete understanding of gastropod evolution and for evolutionary processes in general.

Annotation↗
PubMed2026

Discovery and evolution of endogenous retroviruses in the genome of crab-eating macaque (Macaca fascicularis).

Endogenous retroviruses (ERVs) are a dynamic and biologically significant component of vertebrate genomes, with integration events spanning deep evolutionary time. The crab-eating macaque (Macaca fascicularis) is an important non-human primate model for biomedical research because of its close phylogenetic relationship to humans and its conservation status as an endangered species. However, the ERV complement of its genome has not been systematically characterized. Using the current highest-quality chromosome-level genome assembly for this species, we performed a genome-wide, homology-based survey of relatively intact ERV proviruses in M. fascicularis. We identified 106 proviral loci distributed across all chromosomes. Phylogenetic reconstruction based on conserved reverse transcriptase domains classified these elements into β-, γ-, and unclassified lineages, with β- and γ-retroviral lineages predominating. LTR divergence-based dating indicated that these proviruses represent multiple waves of historical retroviral activity and span a broad range of integration ages. This curated dataset provides a high-confidence reference set for investigating the evolutionary history and genomic impact of preserved ERV proviruses in an endangered primate model; however, it does not include degraded ERV fragments or solo LTRs.

Animals↗
PubMed2025

Repeatable Genomic Outcomes Along the Speciation Continuum: Insights From Pine Hybrid Zones (Genus Pinus).

Hybridization is a widespread evolutionary process and a key source of evolutionary novelty. Despite intensive study, the extent to which hybridization is deterministic and repeatable, particularly in recurrent contact events involving the same species under varying ecological conditions, remains unclear. Here, we investigated three replicated contact zones between Scots pine (Pinus sylvestris) and dwarf mountain pine (Pinus mugo) in Central Europe: two occurring in peatland habitats and one in a contrasting sandstone outcrop. Using genome-wide SNP genotyping of over 1300 individuals, we analysed genomic structure, diversity, and ancestry patterns across these zones. All sites revealed pervasive hybridization, dominated by later-generation hybrids and a notable scarcity of pure P. mugo. Across environments, hybrid populations exhibited strikingly consistent genomic compositions, with asymmetric introgression strongly biased toward P. mugo ancestry, suggesting that hybrid genome structure may follow predictable patterns under similar ecological conditions and could be shaped by cytonuclear incompatibilities. Nonetheless, we also detected site-specific differences in hybrid diversity and phenotype, highlighting the influence of local environmental selection on shared hybrid genomic backgrounds. We provide genomic evidence that Pinus uliginosa, a morphologically distinct peat bog pine traditionally regarded as a relict and endangered species is instead a partially stabilised hybrid lineage. Its genome reflects incomplete hybridization and ecological filtering, yet it lacks sufficient genetic divergence to be recognised as a distinct species. Together, these results provide evidence for the repeatability of hybridization processes, which result in the formation of phenotypes reflecting a species continuum subjected to strong environmental pressures. The findings support the simplification of taxonomic nomenclature within the Pinus mugo complex, informing adaptive conservation strategies and the genetic management of hybrid lineages.

Hybridization, Genetic↗
PubMed2025

Migration strategies, connectivity and corridor features of the partial migrant little bustard (Tetrax tetrax) across the Iberian Peninsula.

The study of migration ecology is crucial for understanding the factors and pressures affecting migratory species. Here, we studied the migratory ecology of the little bustard (Tetrax tetrax), a steppe bird that has suffered a sharp decline over recent decades, mainly due to agricultural intensification. Using 105 adult birds tagged across the main Iberian regions where the species is present (Alentejo, Extremadura, Ebro Valley, Northern Plateau, Southern Plateau and Guadalquivir Valley), we analysed the ratio of migratory and resident birds in each population and assessed their connectivity during the three main migratory periods (summer, winter and pre-breeding). Additionally, we describe the features of the migrations recorded in terms of length, duration and day period. Our results corroborate that little bustards can be considered partial migrants across Iberia, although the proportion of residents versus migrants varied between populations: the Alentejo (94.74%) and Northern Plateau (93.75%) had the highest proportion of migrants, followed by Guadalquivir Valley (81.82%), Extremadura (65.38%), Southern Plateau (55.56%) and Ebro Valley (25.93%). Migratory connectivity varied between periods: the pre-breeding and summering migrations showed a trend to move northwards, while birds moved southwards for winter. Regarding the migratory corridors obtained from the 253 migrations identified, we found three main routes: one corridor that connects the Northern Plateau with the western part of the Southern Plateau and Extremadura, another one that connects the Southern Plateau, Extremadura, Alentejo and Guadalquivir Valley, and one corridor that concentrates migrations within the Ebro Valley, and between the Ebro Valley and the Southern Plateau. Finally, analyses showed that little bustards migrate at night through areas dominated by herbaceous cover (avoiding tree-covered land and water bodies) and of low elevation and terrain roughness. Our results highlight the importance of developing an international and inter-regional conservation strategy to protect not only the breeding and wintering quarters, but also this endangered species' migratory corridors, thus supporting the viability of the metapopulation.

Brownian bridge kernel↗
PubMed2026

Complete biosynthesis of the anticancer cephalotaxinone and homoerythratine.

Cephalotaxine-type and homoerythrina-type alkaloids are structurally unique and biologically important natural products isolated from endangered species that belong to the genus Cephalotaxus. Among them, homoharringtonine (HHT [1]) is a marketed drug used to treat leukemia. However, the scalable production of HHT is significantly hindered by limited natural resources. Despite intensive investigation over half a century, the complete biosynthetic pathways of these alkaloids remain unknown. Here, we applied a comprehensive multi-omics analysis and used a set of chemically synthesized standard compounds to identify the missing enzymes required for the biosynthesis of cephalotaxinone and homoerythratine. We also uncovered a rare case of divergent oxidation catalyzed by two highly homologous cytochrome P450 enzymes, CfCYP2 and CfCYP3, in the biosynthesis of two structurally distinct alkaloids. We further identified the key residues that significantly affect the divergent oxidation outcomes and ultimately reconstituted the complete biosynthetic pathways for producing these two alkaloids in N. benthamiana.

Cephalotaxus↗