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PubMed2026

Reconstruction of ancestral plant genomes for inter-crop translational research.

We present Ancestral Genome Reconstruction (AGR), an exploratory framework for the automated inference of "paleogenomes" from large-scale comparative datasets. By analyzing 84 extant angiosperm species, we reconstructed 10 key ancestral angiosperm genomes millions of years old. These reconstructed ancestors were instrumental in (1) estimating when angiosperms emerged, when major botanical families originated, and when shared ancestral whole-genome duplication events occurred; and (2) tracing the evolutionary trajectories of ancestral chromosomes and genes, especially those that may have driven the emergence of key life-history traits (e.g., woody vs. herbaceous, aquatic vs. terrestrial, C3 vs. C4, and symbiotic root-nodulating vs. non-nodulating species). We demonstrated that these paleogenomes serve as tractable backbones for inter-crop translational research. Through an open-access web tool, OrthoViewer, we identified orthologs that have retained the same ancestral genomic context, favoring the identification of genes associated with "phenologs"- orthologous genes across species driving analogous phenotypes, traits, or processes-exemplified by FUWA for yield components, FLC for flowering time, and DDM1 for DNA methylation. Taken together, this study provides a testable paleogenomic workflow, opening novel avenues for integrating evolutionary genomics data into modern climate-smart crop breeding and supporting the agroecological transition.

Genome, Plant↗
PubMed2026

Genome-wide identification and evolutionary analysis of the ERF-VII gene family in the tea plant (Camellia sinensis) and functional characterization of CsRAP2.2 in response to cold stress.

The ERF-VII gene family, a critical branch of the AP2/ERF superfamily, is central to plant stress adaptation. However, its evolutionary history and function in tea plant (Camellia sinensis) remain unclear. Here, we performed integrated evolutionary, genomic, and functional analyses of ERF-VII genes across 14 plant lineages and 20 tea plant cultivars. The phylogenetic analysis revealed that ERF-VII proteins originated after vascular plant divergence, coinciding with the emergence of the N-terminal MCGGA/I motif linked to the oxygen-dependent N-degron pathway. Gymnosperms retained few conserved members, whereas angiosperms exhibited lineage-specific expansion-extensive in monocots via whole-genome duplication, moderate in eudicots with functional diversification. Pan-genome analysis across 20 tea plant cultivars further revealed varietal differences in ERF-VII gene distribution. Transcriptome profiling via the Tea Plant Information Archive identified CsRAP2.2 as a cold-inducible ERF-VII member with sustained expression under low-temperature stress. Functional assays demonstrated that silencing CsRAP2.2 reduced cold tolerance, while overexpression in tea leaves and heterologous expression in Arabidopsis thaliana enhanced cold tolerance by maintaining photosystem II efficiency, reducing membrane lipid peroxidation, and improving antioxidant capacity. Weighted gene co-expression network analysis positioned CsRAP2.2 as a regulatory hub integrating cold, hormone, and oxygen-sensing pathways. These results clarify the evolutionary trajectory of ERF-VII genes and establish CsRAP2.2 as a core cold-tolerance regulator in tea plant. These findings may inform future breeding of cold-resilient tea cultivars.

Camellia sinensis↗
PubMed2003

Major life-history transitions by deterministic directional natural selection.

For large-scale evolution on Earth there has been a directional change where simple self-replicators evolved into large organisms with high metabolic rates and long pre-reproductive periods. Associated with this increase there have been major life-history transitions from asomatic, non-senescing, haploid, and asexually reproducing organisms to somatic, senescing, diploid, and sexually reproducing organisms with male and female individuals. Using a game theoretical model, it is shown that this trajectory can be explained by deterministic natural selection as it arises from first principles of the self-replication process in mobile organisms. It is shown (i) that selection for an increase in the energetic state of the organism puts a direction to evolution, (ii) that selection by density-dependent competitive interactions can explain the major life-history transitions as a function of the energetic state of the organism, and (iii) that the two selection processes combined can explain an exponentially increasing body mass. It is also shown (iv) why, for the case with an increasing body mass, we may expect many life histories to evolve in accordance with the exponents of the body mass allometries, (v) that an upper constraint on the body mass and metabolic rate can induce an additional transition into eusocial communities, and (vi) that the evolutionary trajectory is likely reversible with backward evolution during periods of environmental crises.

Animals↗
PubMed2026

Nuclear DNA of plastid origin (NUPTs), neglected driver of genome variation and evolutionary innovation.

Plant nuclear genomes contain a variable, though typically minor, fraction of DNA sequences of plastid origin known as NUPTs. Unlike the massive transfer of DNA and genes from the proto-organelle genome to the nucleus that occurred during the endosymbiotic event that gave rise to plastids, the formation of NUPTs is an ongoing process that does not imply concomitant DNA loss. Although NUPTs are generally considered to be potentially deleterious insertions that are continuously generated and rapidly eliminated at near-constant turnover rates, accumulating evidence reveals alternative evolutionary trajectories. In this review, we discuss recent findings that highlight the episodic formation of NUPTs, their subsequent proliferation, and their eventual long-term fixation within the nuclear genome. We also explore their non-random spatial association with specific genomic elements. NUPTs show preferential overlap with specific superfamilies of transposable elements, which may facilitate their proliferation and dispersal throughout the nuclear genome. Regarding protein-coding genes, the contribution of NUPTs varies among species. In contrast, NUPTs are found to be consistently enriched among certain classes of non-coding RNA genes, notably rRNA, tRNA, and specific regulatory RNA families, suggesting that they are involved in the evolution of gene regulation and translational machinery. Overall, these findings underscore the unexpected complexity of the mechanisms underlying NUPT formation and support the idea that they are a significant source of genome variation and evolutionary innovation. Further research is necessary to fully elucidate the mechanisms underlying NUPT formation, as well as to determine their potential adaptive significance in plant genome evolution.

Plastids↗
PubMed2025

Comparative genomic analysis of Artemisia argyi reveals asymmetric expansion of terpene synthases and conservation of artemisinin biosynthesis.

Artemisia argyi, a perennial herb of the Asteraceae family, possesses significant therapeutic and economic value. We present a 7.88 Gb chromosome-level haplotype-resolved genome assembly, revealing its unique evolutionary trajectory. The karyotype (2n = 34) of A. argyi is that of an autotetraploid, which underwent gametic chromosome fusion prior to species-specific whole-genome duplication (WGD-3). The genome exhibits pronounced multivalent chromosome pairing and frequent recombination among homologous groups. Asymmetrical evolution following WGD-3 is a hallmark feature, evidenced by imbalanced allelic gene loss and widespread neofunctionalization. The terpene synthase (TPS) gene family exemplifies this pattern, having expanded through four duplication events in A. argyi. Recent tandem duplications and allelic functional differentiation have generated substantial gene functional diversity. Notably, we identified a tandem-duplicated six-copy ADS homolog (AarADS)-a key TPS gene in the artemisinin biosynthetic pathway of Artemisia annua (AanADS)-localized exclusively to a single chromosome in A. argyi. Unlike AanADS, which converts farnesyl pyrophosphate (FPP) to amorpha-4,11-diene, AarADS catalyzes FPP to α-bisabolol. Evolutionary analysis suggested that AanADS acquired its specialized function via a derived mutation in the A. annua lineage. This study elucidates the genomic evolution underpinning A. argyi's distinctive medicinal properties.

Alkyl and Aryl Transferases↗
PubMed2026

Large-scale genomic analysis places Chinese CC398 as a persistent human-associated MSSA lineage apart from the dominant global LA-MRSA clade.

Staphylococcus aureus clonal complex (CC)398 has emerged as a dominant livestock-associated methicillin-resistant S. aureus (LA-MRSA) lineage worldwide; however, its evolutionary trajectory and regional diversification remain incompletely understood. We developed a core-genome multilocus sequence typing (cgMLST) scheme with hierarchical clustering and applied it to over 30,000 S. aureus genomes, revealing frequent cross-border transmission of CC398. Subsequent time-calibrated phylogenetic analysis placed the most recent common ancestor at 1942 (95% CI: 1939-1945), with the human-to-livestock host jump around 1969 (95% CI: 1968-1972). Chinese CC398 exhibits a distinct trajectory: unlike the LA-MRSA lineages dominating Europe and North America, Chinese isolates are predominantly human-associated methicillin-susceptible S. aureus (HA-MSSA), forming unique East Asia-specific phylogroups (SAP1, SAP2, and AP1-AP3), with distinct resistance and virulence profiles. The LA lineage remains limited in China, with multinational mixed clusters emerging only after 2019. Analysis of global transmission networks revealed a significant correlation between LA-CC398 spread and international trade in fresh swine products, while no such correlation was observed for the human-associated lineage. Beyond the established lineage markers tet(M) and scn, our analysis identified additional differentially distributed genes, including cadC-a chromosomal cadmium resistance regulator-as a novel HA-lineage-enriched gene whose functional role in host adaptation remains to be determined. This study reveals that CC398 followed fundamentally different evolutionary paths in China versus Western countries, challenging a one-size-fits-all model of its dissemination.IMPORTANCEThis study illustrates how large-scale microbial genomics can resolve the evolutionary origins and regional diversification of bacterial pathogens. By applying a novel cgMLST scheme to over 30,000 S. aureus genomes, we show that CC398 followed fundamentally different evolutionary paths in China versus Western countries-challenging the prevailing model of uniform global dissemination-and that livestock-associated MRSA expansion is closely linked to international trade in fresh pork products. These findings highlight the need for integrated surveillance across human, animal, and trade interfaces to anticipate the emergence and spread of zoonotic pathogens.

Staphylococcus aureus↗
PubMed2026

Beyond Morphology: Reframing Lymph-Node Metastasis Prediction Through Clonal Ecology-Decades-Long Genomic Instability and Polyclonal-to-Monoclonal Transitions as the Missing Dimension in Cancer.

Recent whole-genome, lineage-tracing, single-cell, and spatial studies have reshaped our understanding of tumor evolution, revealing that cancers can arise from polyclonal populations, undergo decades-long genomic instability before clinical detection, and progress through dynamic changes in subclonal composition, cellular state, and ecological organization. These findings challenge the assumption underlying morphology-based prediction models that metastatic risk can be inferred from static histological features alone. Here, we revisit lymph-node metastasis prediction in colorectal cancer through clonal ecology, integrating computational pathology with evolutionary oncology. Drawing on the subclonal switchboard model proposed in 2012 and subsequent artificial intelligence (AI)-enabled approaches for tracking dominant and dormant subclones, we synthesize evidence that metastatic potential reflects clonal ancestry, evolutionary timing, spatial niche architecture, cellular plasticity, intercellular interactions, dormancy, and treatment-driven shifts in subclonal fitness. We define five complementary methodological pillars for operationalizing clonal ecology: single-cell transcriptomics for resolving rare subclones, evolutionary trajectories, and adaptive cell states; lineage tracing and phylogenetics for reconstructing clonal ancestry and divergence; spatial transcriptomics and genomics for mapping subclonal geography and tumor-stromal-immune interactions; longitudinal liquid biopsy surveillance for monitoring residual disease, clonal turnover, and emerging resistance; and AI-enabled multimodal integration for connecting histopathology, genomics, spatial biology, and longitudinal data into predictive ecological-state models. Multiple-instance learning and pathology foundation models provide scalable computational foundations for evolution-aware prediction. Translationally, dormant subclones represent actionable reservoirs of recurrence. A longitudinal clinical and experimental study of KMT2A-rearranged acute myeloid leukemia further supports central predictions of the subclonal switchboard framework by demonstrating treatment-associated shifts in subclonal dominance, persistence of cryptic adaptive programs, and ecological rewiring during resistance and relapse. We propose clonal ecology as a measurable dimension for extending morphology-driven prediction toward integrative models that anticipate evolutionary transitions, identify therapeutic windows, and proactively constrain adaptive tumor ecosystems before resistant or metastatic subclones achieve clinical dominance.

Humans↗
PubMed2026

Proteobacteria with chemosynthetic potential are highly prevalent in the gills of Hypoplectrus reef fishes.

Fishes host a diverse microbiome in their gills, but a broad characterization of this microbiome at the metagenomic level is lacking. Here, we apply genome-resolved metagenomics to the gills of the hamlets (Hypoplectrus spp), a group of reef fishes from the Greater Caribbean. The analysis of 353 gill samples from 15 hamlet species collected at eight locations over 13 years revealed a stark contrast between the gill microbiota and reef water microbial communities, indicating a distinct and specific gill microbiome. A total of 70 gill-associated metagenome-assembled genomes (MAGs) were recovered. These MAGs belong to 17 lineages, most of which are novel. They relate to known fish gill pathogens, fish gut microbes, free-living and biofilm-associated taxa, indicating that the gill microbiome was assembled from a collection of distinct eco-evolutionary trajectories. The MAGs harbor diverse metabolic modules, involved notably in nitrogen cycling, antibiotic production and biofilm formation, revealing a highly dynamic microbial ecosystem. One lineage in the Burkholderiaceae family was outstandingly prevalent across fish host species, sampling locations and years. Its genome encoded complete metabolic modules for carbon fixation and sulfur oxidation, indicating chemosynthetic potential. To the best of our knowledge, this is the first line of evidence that fishes may host sulfur-oxidizing chemosynthetic bacteria in their gills. The functional significance of this chemosynthetic potential for the fish host or other members of the gill microbiome remains to be established. The high prevalence of this lineage allowed to build a pangenome. It revealed large-scale geographic structure (western Caribbean, eastern Caribbean and Gulf of Mexico), which parallels the phylogenomic pattern observed in the hamlets. Overall, our findings point to complex fish host-microbe and microbe-microbe eco-evolutionary interactions in the gills that may influence fish physiology, homeostasis and immune response.

Animals↗
PubMed2026

Parental niche construction buffers microbial and competitive challenges and drives offspring dependence in burying beetles.

Parents across diverse taxa modify the biotic or abiotic environments of their offspring. Such modifications may constitute ecological inheritance and are central to developmental niche construction, whereby organisms shape developmental conditions and selective pressures experienced by the next generation. Despite its theoretical importance, parental niche construction is often studied under simplified conditions or by focusing on single components of care, limiting our understanding of how multiple parental modifications interact in ecologically relevant contexts, whether they buffer environmental heterogeneity, and how this shapes offspring development and evolutionary trajectories. Using the burying beetle Nicrophorus vespilloides, we investigated how parents jointly modify chemical and microbial properties of vertebrate carcasses, a highly contested resource on which offspring develop. We show that under natural microbial and competitive conditions, prehatch care enhances larval survival and growth, alters cadaveric volatile emissions, and reduces carcass attractiveness to competitors. While soil type shapes carcass-associated microbial communities, parental care buffers these environmental effects, creating a more consistent microbiome and reducing environmentally induced larval mortality. Larvae of the related species Ptomascopus morio, which lacks prehatch carcass preparation, survived equally well on prepared and unmodified carcasses, whereas N. vespilloides larvae showed reduced survival on unmodified carcasses. This contrast is consistent with the hypothesis that N. vespilloides larvae have evolved a reliance on a parentally constructed developmental environment. Together, these findings show that parental care can constitute an integrated form of niche construction that reshapes developmental environments, enhances offspring performance, and may promote evolutionary feedback leading to increased offspring dependence on parental care.

Animals↗
PubMed2026

Comparative Transcriptomic Analyses Identify Candidate Genes for Convergent Reproductive Shifts in a Bimodal Viviparous Amphibian.

Shifts in reproductive mode represent key evolutionary innovations that shape species' life histories and evolutionary trajectories. Species showing bimodal reproductive strategies with multiple independent origins offer a rare opportunity to gain insights into the adaptive processes and mechanisms underlying convergent traits. The fire salamander, Salamandra salamandra, is the only amphibian exhibiting intraspecific variation in reproductive mode across multiple independent reproductive shifts, enabling investigation of the transition between larviparity (females give birth to aquatic larvae) and pueriparity (females give birth to fully developed terrestrial juveniles) within a single species and across different timescales. Pueriparity is an adaptive innovation that skips the aquatic larval stage, allowing individuals to exploit habitats with no available water bodies. The fire salamander is larviparous across most of its range, but pueriparity has evolved independently at least three times: once in the early Pleistocene within S. s. bernardezi in the mountains of northern Spain, and more recently on two land-bridge islands (NW Spain) inhabited by S. s. gallaica. To identify candidate genes associated with these distinct reproductive modes, we compared gene expression profiles of the uterus and oviduct of pregnant females across two independent evolutionary transitions using RNA-sequencing. We detected shared changes in maternal gene expression among pueriparous S. s. bernardezi and S. s. gallaica relative to their larviparous counterparts, in addition to differences unique to each independent evolutionary transition. Functional enrichment analyses indicated that differentially expressed genes were associated with reproductive timing, angiogenesis, and maternal signalling, consistent with the phenotypic differences observed in the uterine environment and embryonic development between the two reproductive modes. This study represents an important first step towards understanding the genomic basis of the evolution of pueriparity in a remarkable bimodal reproductive system, and provides transcriptomic resources and candidate genes for future research into the genomic architecture underlying this poorly understood adaptive trait.

Animals↗
PubMed2025

The evolution of the plastid genomes in the holoparasitic Balanophoraceae.

The independent transition to a heterotrophic lifestyle in plants drove remarkably convergent evolutionary trajectories, characterized by morphological modifications and reductions in their plastomes. The characteristics of the minimum plastome required for survival, if they exist, remain a topic of debate. The holoparasitic family Balanophoraceae was initially presumed to have entirely lost their plastids, however, recent reports revealed the presence of reduced and aberrant plastids with odd genomes. Among the outstanding features of these genomes are the highest nucleotide composition bias across the tree of life and the only two genetic code changes ever recorded among plants. In this study, we assembled the plastomes from five genera, four of which had never been studied. Major common features include extremely high AT content, the lack of a typical quadripartite structure and extensive size reduction due to gene elimination and genome compaction. The family exhibits multiple gene and intron losses, and a broad range of scenarios regarding the evolution of the plastid trnE, a gene considered essential because of its dual function in tetrapyrrole biosynthesis and translation within the plastid. In addition, phylogenetic analyses suggest that the genus Scybalium is not monophyletic. An evolutionary model for the plastomes of the Balanophoraceae is proposed.

Genome, Plastid↗
PubMed2004

Evolution of vertebrate genes related to prion and Shadoo proteins--clues from comparative genomic analysis.

Recent findings of new genes in fish related to the prion protein (PrP) gene PRNP, including our recent report of SPRN coding for Shadoo (Sho) protein found also in mammals, raise issues of their function and evolution. Here we report additional novel fish genes found in public databases, including a duplicated SPRN gene, SPRNB, in Fugu, Tetraodon, carp, and zebrafish encoding the Sho2 protein, and we use comparative genomic analysis to analyze the evolutionary relationships and to infer evolutionary trajectories of the complete data set. Phylogenetic footprinting performed on aligned human, mouse, and Fugu SPRN genes to define candidate regulatory promoter regions, detected 16 conserved motifs, three of which are known transcription factor-binding sites for a receptor and transcription factors specific to or associated with expression in brain. This result and other homology-based (VISTA global genomic alignment; protein sequence alignment and phylogenetics) and context-dependent (genomic context; relative gene order and orientation) criteria indicate fish and mammalian SPRN genes are orthologous and suggest a strongly conserved basic function in brain. Whereas tetrapod PRNPs share context with the analogous stPrP-2-coding gene in fish, their sequences are diverged, suggesting that the tetrapod and fish genes are likely to have significantly different functions. Phylogenetic analysis predicts the SPRN/SPRNB duplication occurred before divergence of fish from tetrapods, whereas that of stPrP-1 and stPrP-2 occurred in fish. Whereas Sho appears to have a conserved function in vertebrate brain, PrP seems to have an adaptive role fine-tuned in a lineage-specific fashion. An evolutionary model consistent with our findings and literature knowledge is proposed that has an ancestral prevertebrate SPRN-like gene leading to all vertebrate PrP-related and Sho-related genes. This provides a new framework for exploring the evolution of this unusual family of proteins and for searching for members in other fish branches and intermediate vertebrate groups.

Animals↗
PubMed2005

Three Prochlorococcus cyanophage genomes: signature features and ecological interpretations.

The oceanic cyanobacteria Prochlorococcus are globally important, ecologically diverse primary producers. It is thought that their viruses (phages) mediate population sizes and affect the evolutionary trajectories of their hosts. Here we present an analysis of genomes from three Prochlorococcus phages: a podovirus and two myoviruses. The morphology, overall genome features, and gene content of these phages suggest that they are quite similar to T7-like (P-SSP7) and T4-like (P-SSM2 and P-SSM4) phages. Using the existing phage taxonomic framework as a guideline, we examined genome sequences to establish "core" genes for each phage group. We found the podovirus contained 15 of 26 core T7-like genes and the two myoviruses contained 43 and 42 of 75 core T4-like genes. In addition to these core genes, each genome contains a significant number of "cyanobacterial" genes, i.e., genes with significant best BLAST hits to genes found in cyanobacteria. Some of these, we speculate, represent "signature" cyanophage genes. For example, all three phage genomes contain photosynthetic genes (psbA, hliP) that are thought to help maintain host photosynthetic activity during infection, as well as an aldolase family gene (talC) that could facilitate alternative routes of carbon metabolism during infection. The podovirus genome also contains an integrase gene (int) and other features that suggest it is capable of integrating into its host. If indeed it is, this would be unprecedented among cultured T7-like phages or marine cyanophages and would have significant evolutionary and ecological implications for phage and host. Further, both myoviruses contain phosphate-inducible genes (phoH and pstS) that are likely to be important for phage and host responses to phosphate stress, a commonly limiting nutrient in marine systems. Thus, these marine cyanophages appear to be variations of two well-known phages-T7 and T4-but contain genes that, if functional, reflect adaptations for infection of photosynthetic hosts in low-nutrient oceanic environments.

Bacteriophage T7↗
PubMed2000

Jaws and teeth of Australopithecus afarensis from Maka, Middle Awash, Ethiopia.

The Maka locality in Ethiopia's Middle Awash area has yielded new craniodental remains dated to 3.4 million years (myr) in age. These remains are described and assessed functionally and systematically. The fossils are assigned to Australopithecus afarensis. Maka thus joins Hadar and Laetoli as the third major locality yielding this species. As with previous site samples, the Maka collection displays a wide range of size variation. The nearly complete and undistorted MAK-VP-1/12 adult mandible from Maka is an excellent match for Hadar and Laetoli counterparts, confirming the geographic and temporal distribution of A. afarensis. This specimen shows that this taxon is functionally and developmentally hominid in its incisor/canine/premolar complex. A postulated evolutionary trajectory through A. anamensis to A. afarensis would have involved postcanine megadontia and other adaptations to a more heavily masticated diet relative to the earlier Ardipithecus ramidus.

Adult↗
PubMed1997

The foldability landscape of model proteins.

Molecular evolution may be considered as a walk in a multidimensional fitness landscape, where the fitness at each point is associated with features such as the function, stability, and survivability of these molecules. We present a simple model for the evolution of protein sequences on a landscape with a precisely defined fitness function. We use simple lattice models to represent protein structures, with the ability of a protein sequence to fold into the structure with lowest energy, quantified as the foldability, representing the fitness of the sequence. The foldability of the sequence is characterized based on the spin glass model of protein folding. We consider evolution as a walk in this foldability landscape and study the nature of the landscape and the resulting dynamics. Selective pressure is explicitly included in this model in the form of a minimum foldability requirement. We find that different native structures are not evenly distributed in interaction space, with similar structures and structures with similar optimal foldabilities clustered together. Evolving proteins marginally fulfill the selective criteria of foldability. As the selective pressure is increased, evolutionary trajectories become increasingly confined to "neutral networks," where the sequence and the interactions can be significantly changed while a constant structure is maintained.

Amino Acid Sequence↗
PubMed2026

Tandem Duplication-Driven Neofunctionalization of UDP-Glycosyltransferases Shapes the Diversification of Triterpenoid Saponins in the Cucurbitaceae.

Tandem duplication of tailoring enzymes allows evolutionary innovation that diversifies plant specialized metabolism. Here, we present an interesting example of how tandem duplicated UDP-glycosyltransferases undergo neofunctionalization and shape the chemical diversity of triterpenoid saponins in the Cucurbitaceae family. A chromosome-level genome of Siraitia grosvenorii was assembled and aligned with multiple cucurbit genomes, revealing a specific UGT73AM tandem duplication responsible for regio-selective glycosylation (e.g. the rare 1,4-linked disaccharide) of diverse saponins such as mogrosides, ginsenosides, and momordicines. Comparative genomics depicted the evolutionary trajectory of a universal saponin-biosynthesizing UGT73 tandem arrays syntenously preserved across core eudicots, where lineage-specific UGT copies contribute to distinct metabolic phenotypes. A crystal structure of SgUGT73AM30 (mogrol 25-O-glycosyltransferase) in complex with UDP and mogrol was obtained to elucidate the molecular basis of the regio-specific decoration on vicinal diol of the substrates. Altogether, these findings provide insights into tandem duplication-driven diversification of glycosyltransferases and lay the foundation for engineered glycosylation of valuable triterpenoid saponins.

Saponins↗
PubMed2005

Unique ramus anatomy for Neandertals?

The ramus of Neandertal mandibles is said to show a suite of uniquely Neandertal character states that demonstrate the independent course of Neandertal evolution. This is the latest of numerous attempts to define cranial and mandibular autapomorphies for Neandertals. We examine variation in the four presumably autapomorphic ramal features and show they are neither monomorhic within Neandertals (to the contrary Neandertals are at least as variable as other human samples) nor unique to Neandertals, since they regularly appear in populations predating and postdating them. Neandertals differ from other human populations, both contemporary and recent, but the question of whether this fact reflects a divergent evolutionary trajectory must be addressed by the pattern of differences. In this case, as in the other attempts to establish Neandertal autapomorphies, rather than showing restricted variation and increased specialization, the Neandertal sample shows that the range of human variation in the recent past encompasses, and in some cases exceeds, human variation today, even in the very features claimed to be autapomorphic.

Animals↗
PubMed2004

Arthropod defensins illuminate the divergence of scorpion neurotoxins.

Defensins are phylogenetically ancient antibacterial polypeptides found in plants and animals. Isolation of the cDNA and genomic sequences encoding the scorpion (Leiurus quinquestriatus hebraeus) defensin revealed similarity to scorpion neurotoxins in gene organization (two exons and a phase I intron) and intron characteristics (conserved acceptor, donor and putative branch sites). This commonality, alongside a similar core structure, protein sequence and bioactivity suggest that arthropod defensins and scorpion neurotoxins share a common ancestor. Interestingly, phylogenetic analysis of defensins and scorpion neurotoxins illuminates for the first time a putative evolutionary trajectory for scorpion sodium and potassium channel neurotoxins.

Amino Acid Sequence↗