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Bivoltinism as an antecedent to eusociality in the paper wasp genus Polistes.

To learn the evolutionary trajectories of caste differentiation in eusocial species is a major goal of sociobiology. We present an explanatory framework for caste evolution in the eusocial wasp genus Polistes (Vespidae), which is a model system for insect eusocial evolution. We hypothesize that Polistes worker and gyne castes stem from two developmental pathways that characterized the bivoltine life cycle of a solitary ancestor. Through individual-based simulations, we show that our mechanistic framework can reproduce colony-level characteristics of Polistes and, thereby, that social castes can emerge from solitary regulatory pathways. Our explanatory framework illustrates, by specific example, a changed perspective for understanding insect social evolution.

Animals↗

Genomics and the irreducible nature of eukaryote cells.

Large-scale comparative genomics in harness with proteomics has substantiated fundamental features of eukaryote cellular evolution. The evolutionary trajectory of modern eukaryotes is distinct from that of prokaryotes. Data from many sources give no direct evidence that eukaryotes evolved by genome fusion between archaea and bacteria. Comparative genomics shows that, under certain ecological settings, sequence loss and cellular simplification are common modes of evolution. Subcellular architecture of eukaryote cells is in part a physical-chemical consequence of molecular crowding; subcellular compartmentation with specialized proteomes is required for the efficient functioning of proteins.

Biological Evolution↗

Origins and evolution of methicillin-resistant Staphylococcus aureus clonal lineages.

Most methicillin-resistant Staphylococcus aureus (MRSA) isolates identified among blood isolates collected in Denmark between 1957 and 1970 belonged to either phage group III or the closely related 83A complex and had a PSTM antibiotype (resistance to penicillin [P], streptomycin [S], tetracycline [T], and methicillin [M]). Recently, some of these isolates were shown to have the same genetic backgrounds as contemporary epidemic MRSA isolates, and Danish methicillin-susceptible S. aureus (MSSA) isolates from the 1960s with a PST antibiotype were proposed to have been the recipients of the mecA gene in those lineages. In this study, we investigated the genetic backgrounds of isolates from the 83A complex that were fully susceptible or resistant to penicillin only in order to try to trace the evolutionary trajectory of contemporary MRSA lineages. We also studied MSSA and MRSA isolates from other phage groups in order to investigate if they had the potential to develop into contemporary MRSA clones. Most susceptible or penicillin-resistant isolates from phage group III or the 83A complex belonged to sequence type 8 (ST8) or ST5, while four isolates were ST254. STs 30, 45 and 25 were represented by MSSA isolates from other phage groups, which also included several singletons. Representatives of most of the current major epidemic MRSA lineages were identified among fully susceptible isolates collected in the 1960s, suggesting that these were MSSA lineages which carried genetic traits important for superior epidemicity before the acquisition of methicillin resistance.

Anti-Bacterial Agents↗

Nucleus-encoded genes for plastid-targeted proteins in Helicosporidium: functional diversity of a cryptic plastid in a parasitic alga.

Plastids are the organelles of plants and algae that house photosynthesis and many other biochemical pathways. Plastids contain a small genome, but most of their proteins are encoded in the nucleus and posttranslationally targeted to the organelle. When plants and algae lose photosynthesis, they virtually always retain a highly reduced "cryptic" plastid. Cryptic plastids are known to exist in many organisms, although their metabolic functions are seldom understood. The best-studied example of a cryptic plastid is from the intracellular malaria parasite, Plasmodium, which has retained a plastid for the biosynthesis of fatty acids, isoprenoids, and heme by the use of plastid-targeted enzymes. To study a completely independent transformation of a photosynthetic plastid to a cryptic plastid in another alga-turned-parasite, we conducted an expressed sequence tag (EST) survey of Helicosporidium. This parasite has recently been recognized as a highly derived green alga. Based on phylogenetic relationships to other plastid homologues and the presence of N-terminal transit peptides, we have identified 20 putatively plastid-targeted enzymes that are involved in a wide variety of metabolic pathways. Overall, the metabolic diversity of the Helicosporidium cryptic plastid exceeds that of the Plasmodium plastid, as it includes representatives of most of the pathways known to operate in the Plasmodium plastid as well as many others. In particular, several amino acid biosynthetic pathways have been retained, including the leucine biosynthesis pathway, which was only recently recognized in plant plastids. These two parasites represent different evolutionary trajectories in plastid metabolic adaptation.

Algal Proteins↗

Genetic interaction between distinct Dobrava hantavirus subtypes in Apodemus agrarius and A. flavicollis in nature.

Dobrava virus (DOBV) occurs in two different rodent species, Apodemus flavicollis (DOBV-Af) and A. agrarius (DOBV-Aa). We sequenced the S and M genomic segments from sympatric DOBV-Af and DOBV-Aa strains which fell into two distinct genetic lineages. Molecular phylogenetic analyses gave evidence for genetic reassortment between S and M segments of DOBV-Af and DOBV-Aa and indicated homologous recombination events in DOBV evolution. DOBV-Af and DOBV-Aa are distinct but also subject to genetic exchanges that affect their evolutionary trajectories.

Animals↗

Emergence of Acinetobacter soli harboring three carbapenemase-encoding genes (blaNDM-1, blaIMP-14, and blaOXA-58) on a single plasmid in an ICU patient.

Acinetobacter soli is an environmentally adaptable species increasingly recognized as an emerging pathogen in hospital settings, particularly in intensive care units (ICUs). In this study, we report the first A. soli isolate from an ICU patient that co-harbors three carbapenemase-encoding genes (blaNDM-1, blaIMP-14, and blaOXA-58) on a single plasmid. Whole-genome sequencing revealed that multidrug resistance in this strain is mediated by a 294,790 bp plasmid, pSLAB-A, carrying 16 antimicrobial resistance genes, including all three carbapenemases. Comparative plasmid analysis showed a highly conserved backbone but identified a unique ~40 kb multidrug-resistance region containing blaNDM-1, blaIMP-14, and eight additional resistance genes. Genetic context analysis indicated that insertion sequences (ISAba125 and ISAba3) and class 1 integrons contribute to the mobilization and accumulation of carbapenemase-encoding genes. Plasmid stability assays demonstrated that pSLAB-A remained stably maintained for more than 90 generations without antibiotic selection. A global survey of the NCBI database identified 15 A. soli strains carrying carbapenemase-encoding genes, most of which were isolated from China, with clinical specimens representing the predominant source. Seven carbapenemase-encoding genes were detected, with blaNDM-1 being the most prevalent. Among eight isolates with complete genomes, all carried carbapenemase-encoding genes on plasmids. Phylogenetic analysis revealed regional dissemination of a clonal lineage across hospitals in Zhejiang Province and sustained nosocomial transmission within a hospital in Taiwan. These findings suggest that the spread of carbapenem resistance in A. soli is largely driven by multidrug-resistance plasmids, facilitating clonal expansion in hospital environments and posing a growing challenge for antimicrobial therapy and infection control in ICUs.IMPORTANCECarbapenem-resistant A. soli is an emerging clinical concern, capable of causing severe invasive infections, including bacteremia, in intensive care unit settings, and its emergence poses substantial challenges to antimicrobial therapy. In this study, we demonstrate that carbapenem resistance in A. soli is predominantly mediated by the acquisition of multidrug-resistance plasmids carrying carbapenemase-encoding genes. Owing to its strong environmental persistence, A. soli can readily undergo nosocomial clonal dissemination once carbapenem resistance is acquired. Moreover, the spread of multidrug plasmids co-harboring multiple carbapenemase-encoding genes may accelerate the evolutionary trajectory of resistance in A. soli, further exacerbating the threat to clinical management. Given its demonstrated capacity to cause hospital-associated infections and to rapidly acquire multidrug resistance, A. soli warrants heightened vigilance from both clinical and public health perspectives.

beta-Lactamases↗

Genomic characterization of KPC-2 and NDM coproducing carbapenem-resistant Klebsiella pneumoniae in a hospital: discovery of ST1869 clone and a novel hybrid plasmid.

UNLABELLED: To characterize the plasmid architecture and molecular background of KPC-NDM coproducing carbapenem-resistant Klebsiella pneumoniae (KN-CRKP) in a South China hospital. Five KN-CRKP isolates were collected, including three from one patient. All underwent Illumina sequencing; two (ST11 and ST1869) additionally had Nanopore sequencing. Antimicrobial susceptibility testing strain sequence types, conjugation assays, resistance gene profiling, plasmid typing, genetic structure comparison, core-genome single nucleotide polymorphisms (SNPs) analysis, and plasmid clustering were performed. All isolates exhibited an imipenem minimum inhibitory concentration (MIC) of ≥128 µg/mL and harbored multiple resistance genes. One isolate (1/5) belonged to ST1869 and co-harbored blaKPC-2 and blaNDM-5. The blaNDM-5-carrying plasmid was a novel IncI1/X3 fusion plasmid that also carried blaCMY-42. Unlike several IncX3 plasmids carrying blaNDM in publicly available KN-CRKP genomes from South China, this IncI1/X3 hybrid lacked a complete conjugative transfer system. ST11 was the predominant clone (4/5), co-harboring blaKPC-2 and blaNDM-1. A rare genetic structure, ΔISKpn6-blaKPC-2-ISKpn28, was identified on IncFII plasmids carrying blaKPC-2. Plasmid clustering analysis of 126 comparative KN-CRKP genomes showed diverse sequence types and plasmid backgrounds associated with the KPC/NDM co-production pattern. The observed plasmid diversity and structural variation in KN-CRKP support continued genomic surveillance, with particular attention to the ST1869 clone, the novel IncI1/X3 hybrid plasmid harboring blaNDM-5 and blaCMY-42, and the rare "ΔISKpn6-blaKPC-2-ISKpn28" genetic structure. Expanded genomic data on KN-CRKP are needed to further elucidate its resistance mechanisms and plasmid evolutionary trajectories. IMPORTANCE: The co-production of KPC and NDM carbapenemases in Klebsiella pneumoniae poses a formidable threat to clinical antimicrobial therapy, as these enzymes confer resistance to virtually all β-lactam agents, including carbapenems. Here, we report novel genomic features of KN-CRKP in South China, including the emergence of the ST1869 clone, a unique IncI1/X3 hybrid plasmid harboring blaNDM-5 and blaCMY-42, and the rare ΔISKpn6-blaKPC-2-ISKpn28 genetic structure. These findings substantially expand current understanding of plasmid evolution and resistance gene dissemination in this region. The identification of diverse resistance mechanisms and clonal backgrounds supports enhanced genomic surveillance and infection-control awareness for pan-resistant Enterobacterales.

Plasmids↗

The Pathogenesis of Epithelial Ovarian Cancer.

Epithelial ovarian cancer is not a single disease but a group of biologically distinct malignancies that include serous (high-grade and low-grade), endometrioid, clear cell, and mucinous carcinomas, along with other rare subtypes. Integrating clinicopathological analyses, genomic and multiomic data, and experimental investigations in model systems has revealed the pathogenesis of the various histologic subtypes. A unique feature of epithelial ovarian cancer is that most of these tumors are now recognized to arise not from ovarian tissue but from the fallopian tube or endometrium, the latter in the context of ovarian endometriosis. Studies of precursor lesions have revealed complex evolutionary trajectories and the earliest molecular events in their development. Recent single-cell and spatial technologies further elucidate the roles of intratumoral heterogeneity and the tumor microenvironment in disease progression. This review summarizes these advances from the perspective of tissue of origin and highlights their implications for prevention, early detection, and therapeutic development.

Journal Article↗

RNA shape space topology.

The distinction between continuous and discontinuous transitions is a long-standing problem in the theory of evolution. Because continuity is a topological property, we present a formalism that treats the space of phenotypes as a (finite) topological space, with a topology that is derived from the probabilities with which one phenotype is accessible from another through changes at the genotypic level. The shape space of RNA secondary structures is used to illustrate this approach. We show that evolutionary trajectories are continuous if and only if they follow connected paths in phenotype space.

Models, Genetic↗

Natural history of S-adenosylmethionine-binding proteins.

BACKGROUND: S-adenosylmethionine is a source of diverse chemical groups used in biosynthesis and modification of virtually every class of biomolecules. The most notable reaction requiring S-adenosylmethionine, transfer of methyl group, is performed by a large class of enzymes, S-adenosylmethionine-dependent methyltransferases, which have been the focus of considerable structure-function studies. Evolutionary trajectories of these enzymes, and especially of other classes of S-adenosylmethionine-binding proteins, nevertheless, remain poorly understood. We addressed this issue by computational comparison of sequences and structures of various S-adenosylmethionine-binding proteins. RESULTS: Two widespread folds, Rossmann fold and TIM barrel, have been repeatedly used in evolution for diverse types of S-adenosylmethionine conversion. There were also cases of recruitment of other relatively common folds for S-adenosylmethionine binding. Several classes of proteins have unique unrelated folds, specialized for just one type of chemistry and unified by the theme of internal domain duplications. In several cases, functional divergence is evident, when evolutionarily related enzymes have changed the mode of binding and the type of chemical transformation of S-adenosylmethionine. There are also instances of functional convergence, when biochemically similar processes are performed by drastically different classes of S-adenosylmethionine-binding proteins. Comparison of remote sequence similarities and analysis of phyletic patterns suggests that the last universal common ancestor of cellular life had between 10 and 20 S-adenosylmethionine-binding proteins from at least 5 fold classes, providing for S-adenosylmethionine formation, polyamine biosynthesis, and methylation of several substrates, including nucleic acids and peptide chain release factor. CONCLUSION: We have observed several novel relationships between families that were not known to be related before, and defined 15 large superfamilies of SAM-binding proteins, at least 5 of which may have been represented in the last common ancestor.

Amino Acid Sequence↗

Decoding glioblastoma evolution and heterogeneity through mechanistic modeling: implications for clinical translation.

Glioblastoma (GBM) is one of the most aggressive and lethal primary brain tumors in adults, characterized by dynamic clonal evolution and extensive genomic, cellular, spatial, and microenvironmental heterogeneity. Multi-omics studies have revealed that GBM follows complex evolutionary trajectories involving genetic, epigenetic, transcriptional, and immune-microenvironmental remodeling as tumors grow, adapt to the brain microenvironment, and acquire therapeutic resistance. Increasing evidence suggests that GBM may originate from aberrant neural stem or progenitor cells, including those residing in the subventricular zone, and that glioblastoma stem cells (GSCs) contribute to tumor propagation, heterogeneity, and recurrence. A key conceptual challenge is to reconcile hierarchical cancer stem cell models, in which GSCs are viewed as relatively stable tumor-propagating subpopulations, with dynamic state plasticity models, in which stem-like properties can be reversibly acquired or lost during transitions among proneural-like, mesenchymal-like, invasive, and therapy-tolerant states. Recent advances in single-cell profiling, spatial transcriptomics, lineage tracing, organoid culture, 3D bioprinting, genetically engineered models, and artificial intelligence (AI)-assisted computational modeling have substantially improved the ability to study these processes. However, no currently available model fully recapitulates human GBM heterogeneity, recurrence, treatment history, and tumor-microenvironment interactions. Therefore, model selection should be guided by clearly defined mechanistic questions rather than by reliance on any single platform. This review summarizes current advances in in vitro, ex vivo, in vivo, and computational models for studying GBM evolution and heterogeneity, and discusses how integrated model pipelines may improve preclinical drug testing, treatment-response prediction, and precision neuro-oncology.

Humans↗

Phylogeographic epidemiology of Dabie bandavirus in East Asia: divergent transmission networks and genotype‑linked clinical severity.

BACKGROUND: Severe fever with thrombocytopenia syndrome (SFTS), caused by Dabie bandavirus (SFTSV), exhibits geographically decoupled incidence and fatality patterns across East Asia. We aimed to elucidate the distinct ecological drivers and phylogeographic dynamics underlying this inland-coastal epidemiological divergence. METHODS: Integrating 1820 high-quality global genomes of SFTSV with well-characterized clinical cohorts (936 patients) and nationwide surveillance data (27,457 cases) from China, we constructed a comprehensive analytical framework. Ecological modeling, Bayesian phylogeography, and genotype-phenotype association analyses were employed to trace the evolutionary trajectories and clinical implications of the virus. RESULTS: A pronounced "inland-high-incidence vs. coastal-high-fatality" pattern of SFTS was identified. The incidence of SFTS exhibited divergent sensitivities to meteorological factors; inland transmission was sensitive to thermal fluctuations, whereas coastal dynamics were constrained by a sunshine threshold (>&#x2009;200&#xa0;h/month). In contrast, spatial divergence in clinical severity correlated with the distribution of regional viral genetic structures. Inland regions mainly co-circulated genotypes A, C, and D, while coastal regions were dominated by genotype B. Zhejiang province was identified as a genetic hub with significantly higher recombination frequencies than inland regions (11.0% vs. 3.5%, P < 0.001). Bayesian phylogeographic inference indicated frequent lineage exchange of Zhejiang province in China with the Republic of Korea and Japan. Clinically, genotypes B and D were associated with elevated mortality in coastal and inland regions, respectively, suggesting that the severe coastal phenotype is shaped by its genotype B-dominated structure. Additionally, the RdRp-N828S mutation emerged as a robust molecular correlate of fatal outcomes, warranting further functional validation. CONCLUSIONS: Divergent meteorological factors and plausible maritime transmission networks may underlie the geographically decoupled epidemiology of SFTS. These findings highlight that risk assessment must extend beyond incidence alone and provide a phylogeographically informed framework for targeted surveillance and genotype-specific interventions in high-risk hotspots.

Humans↗

Resonance bands and binary-star formation.

Numerical computations on the evolution of realistically stratified, asymmetric, self-gravitating masses reveal the onset of an instability that is suggestive of, but not decisive for, the formation of a binary star. On the other hand, analysis of the evolution and stability of idealized models consisting of uniform-density ellipsoids has been qualitatively accurate in predicting certain features of the behavior of the more realistically stratified figures. This idealized theory is, therefore, reconsidered in an attempt to isolate additional qualitative features that may be common both to the idealized and to realistic figures, and therefore, serve not only as a guide in formulating issues to be addressed in numerical computations but also as a means of interpreting the outcomes of such calculations. Several such features are isolated in this paper, the most striking of which is the existence and importance of resonance bands of instability encountered by the evolutionary trajectories.

Journal Article↗

A colorful legacy of hybridization in wood-warblers includes frequent sharing of carotenoid genes among species and genera.

Introgression between species has the potential to shape evolutionary trajectories in important ways, but uncovering complex introgression dynamics has only recently been made possible by advances in genomics. Warblers of the avian family Parulidae exemplify rapid diversification and sexual trait divergence, and we endeavored to study historical introgression in the family. We sequenced multiple genomes of nearly every species, constructed a phylogeny for the family, and investigated gene flow across the genome and at genes known for controlling feather color. We found that DNA haplotypes including the gene BCO2, which encodes an enzyme that degrades yellow carotenoids, have spread among genera multiple times-from Vermivora to Geothlypis and from Leiothlypis to multiple Cardellina and Setophaga species. Patterns of inheritance in the latter case point to introgression that occurred 0.5 to 2 million years ago, and the shared haplotype among recipient species is less than 100 nucleotides long. Separately, we found evidence of introgression from red Cardellina species to both of the two red Myioborus species at BDH1L and from one red Myioborus species to the other at CYP2J19; both are key genes in the pathway that converts yellow carotenoids to red ketocarotenoids. Our results show that introgression is a common mechanism for the evolution of colorful plumage in parulid warblers and hint at complex histories of gene flow behind some of the Western Hemisphere's most colorful birds.

Animals↗

The emergence of HIV transmitted resistance in Botswana: "when will the WHO detection threshold be exceeded?".

BACKGROUND: The Botswana antiretroviral program began in 2002 and currently treats 42,000 patients, with a goal of treating 85,000 by 2009. The World Health Organization (WHO) has begun to implement a surveillance system for detecting transmitted resistance that exceeds a threshold of 5%. However, the WHO has not determined when this threshold will be reached. Here we model the Botswana government's treatment plan and predict, to 2009, the likely stochastic evolution of transmitted resistance. METHODS: We developed a model of the stochastic evolution of drug-resistant strains and formulated a birth-death Master equation. We analyzed this equation to obtain an analytical solution of the probabilistic evolutionary trajectory for transmitted resistance, and used treatment and demographic data from Botswana. We determined the temporal dynamics of transmitted resistance as a function of: (i) the transmissibility (i.e., fitness) of the drug-resistant strains that may evolve and (ii) the rate of acquired resistance. RESULTS: Transmitted resistance in Botswana will be unlikely to exceed the WHO's threshold by 2009 even if the rate of acquired resistance is high and the strains that evolve are half as fit as the wild-type strains. However, we also found that transmission of drug-resistant strains in Botswana could increase to approximately 15% by 2009 if the drug-resistant strains that evolve are as fit as the wild-type strains. CONCLUSIONS: Transmitted resistance will only be detected by the WHO (by 2009) if the strains that evolve are extremely fit and acquired resistance is high. Initially after a treatment program is begun a threshold lower than 5% should be used; and we advise that predictions should be made before setting a threshold. Our results indicate that it may be several years before the WHO's surveillance system is likely to detect transmitted resistance in other resource-poor countries that have significantly less ambitious treatment programs than Botswana.

Anti-HIV Agents↗

Global and local ancestry estimation in a captive baboon colony.

The last couple of decades have highlighted the importance of studying hybridization, particularly among primate species, as it allows us to better understand our own evolutionary trajectory. Here, we report on genetic ancestry estimates using dense, full genome data from 881 olive (Papio anubus), yellow (Papio cynocephalus), or olive-yellow crossed captive baboons from the Southwest National Primate Research Center. We calculated global and local ancestry information, imputed low coverage genomes (n = 830) to improve marker quality, and updated the genetic resources of baboons available to assist future studies. We found evidence of historical admixture in some putatively purebred animals and identified errors within the Southwest National Primate Research Center pedigree. We also compared the outputs between two different phasing and imputation pipelines along with two different global ancestry estimation software. There was good agreement between the global ancestry estimation software, with R2 > 0.88, while evidence of phase switch errors increased depending on what phasing and imputation pipeline was used. We also generated updated genetic maps and created a concise set of ancestry informative markers (n = 1,747) to accurately obtain global ancestry estimates.

Animals↗

Enhanced RNA replication and pathogenesis in recent SARS-CoV-2 variants harboring the L260F mutation in NSP6.

The COVID-19 pandemic has been driven by SARS-CoV-2 variants with enhanced transmission and immune escape. Apart from extensive evolution in the Spike protein, non-Spike mutations are accumulating across the entire viral genome and their functional impact is not well understood. To address the contribution of these mutations, we reconstructed genomes of recent Omicron variants with disabled Spike expression (replicons) to systematically compare their RNA replication capabilities independently from Spike. We also used a single reference replicon and complemented it with various Omicron variant Spike proteins to quantify viral entry capabilities in single-round infection assays. Viral entry and RNA replication were negatively correlated, suggesting that as variants evolve reduced entry functions under growing immune pressure on Spike, RNA replication increases as a compensatory mechanism. We identified multiple mutations across the viral genome that enhanced viral RNA replication. NSP6 emerged as a hotspot with a distinct L260F mutation independently arising in the BQ.1.1 and XBB.1.16 variants. Using mutant and revertant NSP6 viral clones, the L260F mutation was validated to enhance viral replication in cells and increase pathogenesis in mice. Notably, this mutation reduced host lipid droplet content by NSP6. Collectively, a systematic analysis of RNA replication of recent Omicron variants defined NSP6's key role in viral RNA replication that provides insight into evolutionary trajectories of recent variants with possible therapeutic implications.

SARS-CoV-2↗

Host hybridization enabled the emergence of a reassorted hantavirus lineage.

The exchange of genetic material between individuals is a key driver of evolution and diversification across most branches of life. Segmented viruses can exchange genetic material through reassortment of genomic segments. New viral strains that emerge from reassortments can have greater infection ranges and higher virulence, although concrete examples of the adaptive advantages of reassortants in nature apart from influenza remain rare. We studied here the evolutionary history and consequences of reassortment in Tula orthohantavirus (TULV) in a hybrid zone between evolutionary lineages of its reservoir host, the common vole (Microtus arvalis). Across 58 trapping sites and 127 infected voles, we detected 27 TULV reassortants in a 12.5 km broad zone at the contact of the parental TULV clades, resembling a viral hybrid zone concordant with the hosts'. Phylogenomic analyses revealed three independent reassortment events, but most of the host hybrid zone was dominated by a single strain with a reassorted M-Segment, which encodes the surface glycoprotein. We detected clade-specific variation in the glycoprotein's N-terminal region consisting of five residues, two of which showed evidence of positive selection. In silico 3D modeling of seven glycoproteins confirmed that this N-terminal region has a unique and specific structure for each TULV clade and the dominant reassortants and is the only structurally variable region of the TULV glycoprotein. Our findings suggest that reassortment between the parental TULV clades in the contact region has resulted in a transgressive virus phenotype potentially adapted to hybrid hosts. This demonstrates the potential of zones of hybridization for the emergence of new virus strains with novel evolutionary trajectories.

Animals↗