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The byrsonimoids include approximately 152 species of trees and shrubs native to the Neotropical region. The clade is monophyletic and consists of three genera: Byrsonima , Blepharandra , and Diacidia. Byrsonima woods are among the most well-known within the Malpighiaceae due to their economic importance. Nonetheless, here for the first time we explore the interspecific stem anatomical diversity of Byrsonima , its similarities and differences to Blepharandra and Diacidia , and how the previously proposed taxonomic circumscriptions for the genus Byrsonima are reflected or not in their wood and bark anatomy. Using a newly reconstructed phylogeny for the Malpighiaceae focusing on the clade Byrsonimoid and a broad selection of species, we conducted phylogenetic comparative analyses to determine how wood and bark traits have evolved across evolutionary time. Our results indicate stem anatomical homogeneity within the clade, particularly in wood traits. On one hand, the presence of septate fibres and prismatic crystals in the rays distinguishes Byrsonima from other members of the clade, but on the other hand, wood and bark traits do not support the classical infrageneric classifications for the genus. The bark in byrsonimoids displays the entire range of variation known for sclerenchyma in this tissue, from cells that can be considered true fibres to fibre-sclereids and typical true sclereids. Ancestral character state reconstructions revealed that radial arrangement, septate fibres, thin heterocellular rays, marginal parenchyma, and prismatic crystals are ancestral traits within the clade, with homoplasy common within the group. These observations demonstrate anatomical conservatism within the Byrsonimoid clade, which might be either related to their proposed recent diversification or a highly effective set of positively selected features. [ABSTRACT FROM AUTHOR]

Introduction: Immunosuppressive diseases, such as chicken infectious anemia virus (CIAV), pose a major threat to livestock farming due to reduced disease resistance, poor vaccine response, and overall poor productivity. CIAV, recognized globally for decades, shows a significant genetic diversity, but its implications remain underexplored. Methods: This study analyzed over 1,000 VP1 sequences and examined CIAV's epidemiology, evolution, and spread with various phylodynamic and phylogeographic approaches. Results: Findings suggest that CIAV likely originated in Japan in the early 20th century, followed by worldwide diversification in two main clades. Both clades exhibited no significant competition and similar global patterns, characterized by a progressive increase until about 2000, when a transient decline was observed for some years, potentially reflecting the increasing use of vaccines. Accordingly, although significant selective pressures were shaping viral evolution, comparable strengths were estimated in the two viral populations. The phylogeographic analysis identified several connections involving also distantly related regions, and more generally, multiple introduction events occurred in several countries and were followed by local evolution, indicative of unconstrained viral circulation. Discussion: Overall, the study highlights the ongoing circulation and evolution of different CIAV variants worldwide, where biosecurity measures and vaccination appear insufficient to prevent viral presence and dispersal. [ABSTRACT FROM AUTHOR]

Background: The increasing amount of genomic data calls for tools that can create genome-scale phylogenies quickly and efficiently. Existing tools rely on large reference databases or require lengthy de novo calculations to identify orthologues, meaning that they have long run times and are limited in their taxonomic scope. To address this, we created getphylo, a python tool for the rapid generation of phylogenetic trees de novo from annotated sequences. Results: We present getphylo (Genbank to Phylogeny), a tool that automatically builds phylogenetic trees from annotated genomes alone. Orthologues are identified heuristically by searching for singletons (single copy genes) across all input genomes and the phylogeny is inferred from a concatenated alignment of all coding sequences by maximum likelihood. We performed a thorough benchmarking of getphylo against two existing tools, autoMLST and GTDB-tk, to show that it can produce trees of comparable quality in a fraction of the time. We also demonstrate the flexibility of getphylo across four case studies including bacterial and eukaryotic genomes, and biosynthetic gene clusters. Conclusions: getphylo is a quick and reliable tool for the automated generation of genome-scale phylogenetic trees. getphylo can produce phylogenies comparable to other software in a fraction of the time, without the need large local databases or intense computation. getphylo can rapidly identify orthologues from a wide variety of datasets regardless of taxonomic or genomic scope. The usability, speed, flexibility of getphylo makes it a valuable addition to the phylogenetics toolkit. [ABSTRACT FROM AUTHOR]

Abstract Background Calcium-dependent protein kinases (CDPKs) phosphorylate downstream target proteins in response to signals transmitted by free calcium ions (Ca2+, one of the second messengers) and thus play important regulatory roles in many biological processes, such as plant growth, development, and stress response. Results A bioinformatic analysis, as well as thorough evolutionary and expression investigations, were conducted to confirm previous reports of functional evidence for plant CDPKs. Using the Phytozome database’s BLAST search engine and the HMM search tool in TBtools software, we discovered that CDPKs are well conserved from green algae to flowering angiosperms in various gene family sizes. Additional investigations of the obtained CDPKs revealed high conservation of domain and motif numbers, gene architectures, and patterns. However, this conservation differed among plant species. Phylogenetic analysis demonstrated that the CDPK gene family diverged from a common ancient gene. Similarly, investigations into plant interspecies evolutionary relationships revealed common ancestral plant species, suggesting speciation of plants and evolution based on plant adaptation and diversification. A search for the driving force of CDPK gene family expansion revealed that dispersed duplication events, among other duplication events, contributed largely to CDPK gene family expansion. Gene localization analysis in P. trichocarpa demonstrated that most CDPK genes are localized within several cell organelles and bind other kinases and proteins to perform their biological functions efficiently. Using RNA-seq data and qPCR analyses, we postulated that PtCDPKs play functional roles in abiotic stress responses by regulating cold, heat, drought and salt stress to varying extents. Conclusion The CDPK genes are well conserved in plants and are critical entities in abiotic stress regulation, and further exploration and manipulation of these genes in the future may provide solutions to some of the challenges in agriculture, forestry and food security.

Background: Calcium-dependent protein kinases (CDPKs) phosphorylate downstream target proteins in response to signals transmitted by free calcium ions (Ca2+, one of the second messengers) and thus play important regulatory roles in many biological processes, such as plant growth, development, and stress response. Results: A bioinformatic analysis, as well as thorough evolutionary and expression investigations, were conducted to confirm previous reports of functional evidence for plant CDPKs. Using the Phytozome database's BLAST search engine and the HMM search tool in TBtools software, we discovered that CDPKs are well conserved from green algae to flowering angiosperms in various gene family sizes. Additional investigations of the obtained CDPKs revealed high conservation of domain and motif numbers, gene architectures, and patterns. However, this conservation differed among plant species. Phylogenetic analysis demonstrated that the CDPK gene family diverged from a common ancient gene. Similarly, investigations into plant interspecies evolutionary relationships revealed common ancestral plant species, suggesting speciation of plants and evolution based on plant adaptation and diversification. A search for the driving force of CDPK gene family expansion revealed that dispersed duplication events, among other duplication events, contributed largely to CDPK gene family expansion. Gene localization analysis in P. trichocarpa demonstrated that most CDPK genes are localized within several cell organelles and bind other kinases and proteins to perform their biological functions efficiently. Using RNA-seq data and qPCR analyses, we postulated that PtCDPKs play functional roles in abiotic stress responses by regulating cold, heat, drought and salt stress to varying extents. Conclusion: The CDPK genes are well conserved in plants and are critical entities in abiotic stress regulation, and further exploration and manipulation of these genes in the future may provide solutions to some of the challenges in agriculture, forestry and food security. [ABSTRACT FROM AUTHOR]

The multigene family of the major histocompatibility complex (MHC) codes for the key antigen-presenting molecules of the vertebrate immune system. In birds, duplicated MHC class II (MHC-II) genes are highly homogenized by concerted evolution, and thus, identification of their orthologous relationships across long evolutionary timescales remains challenging. Relatively low evolutionary rate of avian MHC class IIA genes has been expected to provide a promising avenue to allow such inferences, but availability of MHC-IIA sequences in nonmodel bird species has been limited until recently. Here, taking advantage from accumulating genomic resources, we identified and analyzed MHC-IIA sequences from the most basal lineage of extant birds (Palaeognathae). Conserved region of the MHC-IIA membrane-proximal domain was used to search for orthologous relationships between palaeognath birds and nonavian reptiles. First, analyses of palaeognath sequences revealed the presence of a separate MHC-IIA gene lineage (DAA3) in kiwis, which did not cluster with previously described avian MHC-IIA lineages (DAA1 and DAA2). Next, phylogenetic reconstruction showed that kiwi DAA3 sequences form a single well-supported cluster with turtle MHC-IIA. High similarity of these sequences most likely reflects their remarkable evolutionary conservation and retention of ancient orthologous relationships, which can be traced back to basal archosauromorphs ca. 250 million years ago. Our analyses offer novel insights into macroevolutionary history of the MHC and reinforce the view that rapid accumulation of high-quality genome assemblies across divergent nonmodel species can substantially advance our understanding of gene evolution. [ABSTRACT FROM AUTHOR]

Morphology has been the fundamental and most important source of information in biology. We strongly believe that in the current molecular era of biology, comparative morphology still has an important role to play in understanding life on Earth and ecosystem functioning, bridging the knowledge gap between evolution, systematics, and ecology. [ABSTRACT FROM AUTHOR]

Arthropoda represents the most diverse animal phylum, but clarifying the phylogenetic relationships among arthropod taxa remains challenging given the numerous arthropod lineages that diverged over a short period of time. In order to resolve the most controversial aspects of deep arthropod phylogeny, focusing on the Myriapoda, we conducted phylogenetic analyses based on ten super-matrices comprised of 751 to 1,233 orthologous genes across 64 representative arthropod species, including 28 transcriptomes that were newly generated in this study. Our findings provide unambiguous support for the monophyly of the higher arthropod taxa, Chelicerata, Mandibulata, Myriapoda, Pancrustacea, and Hexapoda, while the Crustacea are paraphyletic, with the class Remipedia supported as the lineage most closely related to hexapods. Within the Hexapoda, our results largely affirm previously proposed phylogenetic relationships among deep hexapod lineages, except that the Paraneoptera (Hemiptera, Thysanoptera, and Psocodea) was recovered as a monophyletic lineage in some analyses. The results corroborated the recently proposed phylogenetic framework of the four myriapod classes, wherein Symphyla and Pauropoda, as well as Chilopoda and Diplopoda, are each proposed to be sister taxa. The findings provide important insights into understanding the phylogeny and evolution of arthropods. [ABSTRACT FROM AUTHOR]

Limnebius exhibits uniform external appearance but variable male genitalia: from differently curved rod shapes in the subgenus Bilimneus to up to seven longitudinally separated folds or appendages in Limnebius s.s.. Among nonsexual traits, two subgenera diverge only in the wing. The aedeagal complexity in Limnebius s.s. is associated with the secondary sexual structures on the abdomen and metatibia; larger body size, which forms two clusters; and male-biased sexual dimorphism. To cluster the subdivisions with phylogenetically unresolved relationships, we examined the coincidence of the traits in both sexes, based on the premise of the independent and monophyletic origin of histologically unsimilar elements. The folds and additional appendages on the median lobe, abdominal paired rows of setae, and protuberances show that the L. parvulus and L. nitidus groups have maximum aedeagal complexity in the L. parvulus and L. nitiduloides subgroups, respectively. The L. parvulus group exhibits a gradual increase in the number of elements of the aedeagi. The histology of connections of the parameres and additional appendages to the median lobe, along with that of the flagellum opening, reveal the subgroups' relationship in the L. nitidus group, as well as a decrease in the complexity of the male genitalia in their recent branches. [ABSTRACT FROM AUTHOR]

The Streptophyta emerged about a billion years ago. Nowadays, this branch of the green lineage is most famous for one of its clades, the land plants (Embryophyta). Although Embryophyta make up the major share of species numbers in Streptophyta, there is a diversity of probably >5000 species of streptophyte algae that form a paraphyletic grade next to land plants. Here, we focus on the deep divergences that gave rise to the diversity of streptophytes, hence particularly on the streptophyte algae. Phylogenomic efforts have not only clarified the position of streptophyte algae relative to land plants, but recent efforts have also begun to unravel the relationships and major radiations within streptophyte algal diversity. We illustrate how new phylogenomic perspectives have changed our view on the evolutionary emergence of key traits, such as intricate signalling networks that are intertwined with multicellular growth and the chemodiverse hotbed from which they emerged. These traits are key for the biology of land plants but were bequeathed from their algal progenitors. [ABSTRACT FROM AUTHOR]

ABSTRACT The Muscomorpha is one of the most species‐rich brachyceran groups in Diptera, with many species serving as important disease vectors; however, its high‐level phylogenetic relationships have long been controversial and unsolved. This study comparatively analyzed the characteristics of mitogenomes of 131 species that represent 18 superfamilies in Muscomorpha, in which mitogenomes of 16 species have been newly sequenced and annotated, demonstrating that their gene composition, order, AT bias, length variation, and codon usage are consistent with documented dipteran mitogenomes. The phylogenetic topologies demonstrated that the robustness of Muscomorpha and major clades within Muscomorpha are monophyletic: Cyclorrhapha, Schizophora, and Calyptratae. A clade of Empidoidea were recovered as the sister group to Cyclorrhapha. Within Cyclorrhapha, Platypezoidea and Syrphoidea were sequentially placed as basal groups of the Cyclorrhapha. The remaining cyclorrhaph superfamilies gathered as two main clades. Ephydroidea were, in most cases, placed as the sister group to Calyptratae. Within Calyptratae, Hippoboscoidea were sister to an assemblage of lineages composed of an Oestroid grade and Muscoidea. The Muscomorpha was proposed to originate in the early Jurassic, and the main clade diversified near the Cretaceous–Paleogene extinction event, estimated using the MCMCtree and six fossil calibration points. The ancestral area of origin and geographic range of Muscomorpha was deduced to be the Palaearctic region with 56.9% probability using the RASP software based on a dated tree.

IntroductionImmunosuppressive diseases, such as chicken infectious anemia virus (CIAV), pose a major threat to livestock farming due to reduced disease resistance, poor vaccine response, and overall poor productivity. CIAV, recognized globally for decades, shows a significant genetic diversity, but its implications remain underexplored.MethodsThis study analyzed over 1,000 VP1 sequences and examined CIAV’s epidemiology, evolution, and spread with various phylodynamic and phylogeographic approaches.ResultsFindings suggest that CIAV likely originated in Japan in the early 20th century, followed by worldwide diversification in two main clades. Both clades exhibited no significant competition and similar global patterns, characterized by a progressive increase until about 2000, when a transient decline was observed for some years, potentially reflecting the increasing use of vaccines. Accordingly, although significant selective pressures were shaping viral evolution, comparable strengths were estimated in the two viral populations. The phylogeographic analysis identified several connections involving also distantly related regions, and more generally, multiple introduction events occurred in several countries and were followed by local evolution, indicative of unconstrained viral circulation.DiscussionOverall, the study highlights the ongoing circulation and evolution of different CIAV variants worldwide, where biosecurity measures and vaccination appear insufficient to prevent viral presence and dispersal.

Abstract Background The deep (> 200 m) ocean floor is often considered to be a refugium of biodiversity; many benthic marine animals appear to share ancient common ancestry with nearshore and terrestrial relatives. Whether this pattern holds for vertebrates is obscured by a poor understanding of the evolutionary history of the oldest marine vertebrate clades. Hagfishes are jawless vertebrates that are either the living sister to all vertebrates or form a clade with lampreys, the only other surviving jawless fishes. Results We use the hagfish fossil record and molecular data for all recognized genera to construct a novel hypothesis for hagfish relationships and diversification. We find that crown hagfishes persisted through three mass extinctions after appearing in the Permian ~ 275 Ma, making them one of the oldest living vertebrate lineages. In contrast to most other deep marine vertebrates, we consistently infer a deep origin of continental slope occupation by hagfishes that dates to the Paleozoic. Conclusion Our results establish hagfishes as ancient members of demersal continental slope faunas and suggest a prolonged accumulation of deep sea jawless vertebrate biodiversity.

A comprehensive and systematic examination of dengue virus (DENV) evolution is essential in Pakistan, where the virus poses a significant public health challenge due to its ability to adapt and evolve. To shed light on the intricate evolutionary patterns of all four DENV serotypes, we analyzed complete genome sequences (n = 43) and Envelope (E) gene sequences (n = 44) of all four DENV serotypes collected in Pakistan from 1994 to 2023, providing a holistic view of their genetic evolution. Our findings revealed that all four serotypes of DENV co-circulate in Pakistan with a close evolutionary relationship between DENV-1 and DENV-3. Among the genetically distinct serotypes DENV-2 and DENV-4, DENV-4 stands out as the most genetically different, while DENV-2 exhibits greater complexity due to the presence of multiple genotypes and the possibility of temporal fluctuations in genotype prevalence. Selective pressure analysis of the Envelope (E) gene revealed heterogeneity among sequences (n = 44), highlighting 46 codons in the genome experiencing selective pressure, characterized by a bias toward balancing selection, indicating genetic stability of the virus. Furthermore, our study suggested an intriguing evolutionary shift of DENV-4 toward the DENV-2 clade, potentially influenced by antibodies with cross-reactivity to multiple serotypes, providing a critical insight into the complex factors, shaping DENV evolution and contributing to the emergence of new serotypes. [ABSTRACT FROM AUTHOR]

Despite the worldwide distribution and rich diversity of the superfamily Tenebrionoidea, the knowledge of the mitochondrial genomes (mtgenome) characteristics of the superfamily is still very limited, and its phylogenetics and evolution remain unresolved. In the present study, we newly sequenced mtgenomes from 19 species belonging to Tenebrionoidea, and a total of 90 mitochondrial genomes from 16 families of Tenebrionoidea were used for phylogenetic analysis. There exist 37 genes for all 82 species of complete mtgenomes of 16 families investigated, and their characteristics are identical as reported mtgenomes of other Tenebrionoids. The Ka/Ks analysis suggests that all 13 PCGs have undergone a strong purifying selection. The phylogenetic analysis suggests the monophyly of Mordellidae, Meloidae, Oedemeridae, Pyrochroidae, Salpingidae, Scraptiidae, Lagriidae, and Tenebrionidae, and the Mordellidae is close to the Ripiphoridae. The "Tenebrionidae clade" and "Meloidae clade" are monophyletic, and both of them are sister groups. In the "Meloidae clade," Meloidae is close to Anthicidae. In the "Tenebrionidae clade," the family Lagriidae and Tenebrionidae are sister groups. The divergence time analysis suggests that Tenebrionoidea originated in the late Jurassic, Meloidae Mordellidae, Lagriidae, and Tenebrionidae in the Cretaceous, Oedemeridae in Paleogene. The work lays a base for the study of mtgenome, phylogenetics, and evolution of the superfamily Tenebrionoidea. [ABSTRACT FROM AUTHOR]

The computational search for the maximum-likelihood phylogenetic tree is an NP-hard problem. As such, current tree search algorithms might result in a tree that is the local optima, not the global one. Here, we introduce a paradigm shift for predicting the maximum-likelihood tree, by approximating long-term gains of likelihood rather than maximizing likelihood gain at each step of the search. Our proposed approach harnesses the power of reinforcement learning to learn an optimal search strategy, aiming at the global optimum of the search space. We show that when analyzing empirical data containing dozens of sequences, the log-likelihood improvement from the starting tree obtained by the reinforcement learning–based agent was 0.969 or higher compared to that achieved by current state-of-the-art techniques. Notably, this performance is attained without the need to perform costly likelihood optimizations apart from the training process, thus potentially allowing for an exponential increase in runtime. We exemplify this for data sets containing 15 sequences of length 18,000 bp and demonstrate that the reinforcement learning–based method is roughly three times faster than the state-of-the-art software. This study illustrates the potential of reinforcement learning in addressing the challenges of phylogenetic tree reconstruction. [ABSTRACT FROM AUTHOR]

Abstract Background Dorcus stag beetles in broad sense are one of the most diverse group in Lucanidae and important saproxylic insects playing a crucial role in nutrient recycling and forest biomonitoring. However, the dazzling morphological differentiations have caused numerous systematic confusion within the big genus, especially the puzzlingly generic taxonomy. So far, there is lack of molecular phylogenetic study to address the chaotic situation. In this study, we undertook mitochondrial genome sequencing of 42 representative species including 18 newly-sequenced ones from Eastern Asia and reconstructed the phylogenetic framework of stag beetles in Dorcus sensu lato for the first time. Results The mitogenome datasets of Dorcus species have indicated the variable mitogenomic lengths ranged from 15,785 to 19,813 bp. Each mitogenome contained 13 PCGs, 2 rRNAs, 22 tRNAs, and a control region, and all PCGs were under strong purifying selection (Ka/Ks

Abstract Herb genomics, at the forefront of traditional Chinese medicine research, combines genomics with traditional practices, facilitating the scientific validation of ancient remedies. This integration enhances public understanding of traditional Chinese medicine’s efficacy and broadens its scope in modern healthcare. Stachys species encompass annual or perennial herbs or small shrubs, exhibiting simple petiolate or sessile leaves. Despite their wide-ranging applications across various fields, molecular data have been lacking, hindering the precise identification and taxonomic elucidation of Stachys species. To address this gap, we assembled the complete chloroplast (CP) genome of Stachys geobombycis and conducted reannotation and comparative analysis of seven additional species within the Stachys genus. The findings demonstrate that the CP genomes of these species exhibit quadripartite structures, with lengths ranging from 14,523 to 150,599 bp. Overall, the genome structure remains relatively conserved, hosting 131 annotated genes, including 87 protein coding genes, 36 tRNA genes, and 8 rRNA genes. Additionally, 78 to 98 SSRs and long repeat sequences were detected , and notably, 6 highly variable regions were identified as potential molecular markers in the CP genome through sequence alignment. Phylogenetic analysis based on Bayesian inference and maximum likelihood methods strongly supported the phylogenetic position of the genus Stachys as a member of Stachydeae tribe. Overall, this comprehensive bioinformatics study of Stachys CP genomes lays the groundwork for phylogenetic classification, plant identification, genetic engineering, evolutionary studies, and breeding research concerning medicinal plants within the Stachys genus.

In the eastern United States, 74 species of Anillini in two genera have been described, with most belonging to Anillinus Casey. Until now, no systematic framework has existed for this large genus, hampering integrative studies. Using DNA sequences from 101 Nearctic species, we present a well-resolved molecular phylogeny supporting a sound systematic framework. Sixteen species groups of Appalachian Anillinus are diagnosed, in part using newly recognized variation in the number of modified male protarsi and the state of the spermathecal duct. We present the first descriptions of Nearctic anilline larvae, which possess none of the synapomorphies of previously described anilline larvae. Within Anillinus, two major clades are mostly consistent with setation of the right paramere: a "hairy clade" with more than four setae, and a "quadrisetose clade." Throughout the phylogeny, microhabitat use varies within each clade, and several endogean lineages are phylogenetically isolated. Our work increases the South Carolina fauna by nearly five-fold. Nine new species are described, Serranillus monadnock sp. nov., Anillinus castaneus sp. nov., Anillinus choestoea sp. nov., Anillinus dentatus sp. nov., Anillinus jancae sp. nov., Anillinus mica sp. nov., Anillinus micamicus sp. nov., Anillinus seneca sp. nov., and Anillinus simplex sp. nov. Several species are newly reported from South Carolina, bringing the total to 20 described species representing seven species groups. Two endemic groups inhabit deep clay soils in the Piedmont and possess unique male sexual characters. The Anillini are a unique component of Nearctic biodiversity, with great potential as a model system for studies of biogeography, secondary male sexual modification, and endogean adaptations. [ABSTRACT FROM AUTHOR]

Herb genomics, at the forefront of traditional Chinese medicine research, combines genomics with traditional practices, facilitating the scientific validation of ancient remedies. This integration enhances public understanding of traditional Chinese medicine's efficacy and broadens its scope in modern healthcare. Stachys species encompass annual or perennial herbs or small shrubs, exhibiting simple petiolate or sessile leaves. Despite their wide-ranging applications across various fields, molecular data have been lacking, hindering the precise identification and taxonomic elucidation of Stachys species. To address this gap, we assembled the complete chloroplast (CP) genome of Stachys geobombycis and conducted reannotation and comparative analysis of seven additional species within the Stachys genus. The findings demonstrate that the CP genomes of these species exhibit quadripartite structures, with lengths ranging from 14,523 to 150,599 bp. Overall, the genome structure remains relatively conserved, hosting 131 annotated genes, including 87 protein coding genes, 36 tRNA genes, and 8 rRNA genes. Additionally, 78 to 98 SSRs and long repeat sequences were detected , and notably, 6 highly variable regions were identified as potential molecular markers in the CP genome through sequence alignment. Phylogenetic analysis based on Bayesian inference and maximum likelihood methods strongly supported the phylogenetic position of the genus Stachys as a member of Stachydeae tribe. Overall, this comprehensive bioinformatics study of Stachys CP genomes lays the groundwork for phylogenetic classification, plant identification, genetic engineering, evolutionary studies, and breeding research concerning medicinal plants within the Stachys genus. [ABSTRACT FROM AUTHOR]

ABSTRACT Bacteria form an intense portion of reading and learning for students enrolled in microbiology education. As a part of the foundational course outline of bacteriology, bacterial classification is a significant topic of discussion. The purpose of our study was to analyze whether bacterial classification can be taught with a phylogenetic tree approach that might be more engaging and beneficial to student learners of microbiology. This methodology is unique compared to the conventional approach applied in introductory lectures of bacteriology that relies on morphology and Gram-staining to classify bacteria. The participants of this study were students enrolled in a two-semester medical school bridge program that offers a Master’s degree in Pre-clinical Sciences. We presented bacterial origin and classification in the light of evolution and used a phylogenetic tree to signify clinically relevant groups of bacteria. Students were also taught the traditional bacterial classification using Gram stains and morphology. Both methods of classification were delivered in a didactic classroom session considering equal time spent and utilizing the same format. An online survey was distributed to the students after the session to collect their feedback. The results from the survey showed that 74% of participants would prefer learning bacterial classification using a combined approach that includes both Gram-staining and morphology as well as the phylogenetic tree. When asked if the study of bacterial classification through an evolutionary tree diagram is a clear and concise way of understanding bacteria, 79% of the students either agreed or strongly agreed with this statement. Interestingly, the alternative phylogenetic tree approach was considered more engaging and regarded as a means to expand the clinical knowledge of bacteria by 78% and 71% of the students, respectively. Overall, our study strongly supports the use of tree-based classification as an additional method to improve the learning of medically important groups of bacteria at varying levels of education.

Abstract Correlated evolution describes how multiple biological traits evolve together. Recently developed methods provide increasingly detailed results of correlated evolution, sometimes at elevated computational costs. Here, we present evo‐scope, a fast and fully automated pipeline with minimal input requirements to compute correlation between discrete traits evolving on a phylogenetic tree. Notably, we improve two of our previously developed tools that efficiently compute statistics of correlated evolution to characterize the nature, such as synergy or antagonism, and the strength of the interdependence between the traits. Furthermore, we improved the running time and implemented several additional features, such as genetic mapping, Bayesian Markov Chain Monte Carlo estimation, consideration of missing data and phylogenetic uncertainty. As an application, we scan a publicly available penicillin resistance data set of Streptococcus pneumoniae and characterize genetic mutations that correlate with antibiotic resistance. The pipeline is accessible both as a self‐contained Github repository (https://github.com/Maxime5G/EvoScope) and through a graphical galaxy interface (https://galaxy.pasteur.fr/u/maximeg/w/evoscope).

Abstract Reconstructing ancestral states for discrete characters is essential for understanding trait evolution in organisms. However, most existing methods are limited to individual characters and often overlook the hierarchical and interactive nature of traits. Recent advances in phylogenetics now offer the possibility of integrating knowledge from anatomy ontologies to reconstruct multiple discrete character histories. Nonetheless, practical applications that fully harness the potential of these new approaches are still lacking. This paper introduces ontophylo, an R package that extends the PARAMO pipeline to address these limitations. Ontophylo enables the reconstruction of phenotypic entities composed of amalgamated characters, such as anatomical regions or entire phenomes. It offers three new applications: (1) reconstruction of evolutionary rates of amalgamated characters using phylogenetic non‐homogeneous Poisson process (pNHPP) that allows modelling rate variation across tree branches and time; (2) reconstruction of morphospace dynamics; and (3) visualization of evolutionary rates on vector images of organisms. Ontophylo incorporates ontological knowledge to facilitate these applications. Benchmarking confirms the accuracy of pNHPP in estimating character rates under different evolutionary scenarios, and example applications demonstrate the utility of ontophylo in studying morphological evolution in Hymenoptera using simulated data. Ontophylo can be easily integrated with other ontology‐oriented and general‐purpose R packages and offers new opportunities to examine morphological evolution on a phenomic scale using new and legacy data.

The current outbreak of coronavirus disease-2019 (COVID-19) caused by SARS-CoV-2 poses unparalleled challenges to global public health. SARS-CoV-2 is a Betacoronavirus, one of four genera belonging to the Coronaviridae subfamily Orthocoronavirinae. Coronaviridae, in turn, are members of the order Nidovirales, a group of enveloped, positive-stranded RNA viruses. Here we present a systematic phylogenetic and evolutionary study based on protein domain architecture, encompassing the entire proteomes of all Orthocoronavirinae, as well as other Nidovirales. This analysis has revealed that the genomic evolution of Nidovirales is associated with extensive gains and losses of protein domains. In Orthocoronavirinae, the sections of the genomes that show the largest divergence in protein domains are found in the proteins encoded in the amino-terminal end of the polyprotein (PP1ab), the spike protein (S), and many of the accessory proteins. The diversity among the accessory proteins is particularly striking, as each subgenus possesses a set of accessory proteins that is almost entirely specific to that subgenus. The only notable exception to this is ORF3b, which is present and orthologous over all Alphacoronaviruses. In contrast, the membrane protein (M), envelope small membrane protein (E), nucleoprotein (N), as well as proteins encoded in the central and carboxy-terminal end of PP1ab (such as the 3C-like protease, RNA-dependent RNA polymerase, and Helicase) show stable domain architectures across all Orthocoronavirinae. This comprehensive analysis of the Coronaviridae domain architecture has important implication for efforts to develop broadly cross-protective coronavirus vaccines.

The coenzyme A (CoA) transferases are a superfamily of proteins central to the metabolism of acetyl-CoA and other CoA thioesters. They are diverse group, catalyzing over a 100 biochemical reactions and spanning all three domains of life. A deeply rooted idea, proposed two decades ago, is these enzymes fall into three families (I, II, and III). Here we find they fall into different families, which we achieve by analyzing all CoA transferases characterized to date. We manually annotated 94 CoA transferases with functional information (including rates of catalysis for 208 reactions) from 97 publications. This represents all enzymes we could find in the primary literature, and it is double the number annotated in four protein databases (BRENDA, KEGG, MetaCyc, UniProt). We found family I transferases are not closely related to each other in terms of sequence, structure, and reactions catalyzed. This family is not even monophyletic. These problems are solved by regrouping the three families into six, including one family with many non-CoA transferases. The problem (and solution) became apparent only by analyzing our large set of manually annotated proteins. It would have been missed if we had used the small number of proteins annotated in UniProt and other databases. Our work is important to understanding the biology of CoA transferases. It also warns investigators doing phylogenetic analyses of proteins to go beyond information in databases.

The type VI secretion system (T6SS) present in many Gram-negative bacteria is a contact-dependent apparatus that can directly deliver secreted effectors or toxins into diverse neighboring cellular targets including both prokaryotic and eukaryotic organisms. Recent reverse genetics studies with T6 core gene loci have indicated the importance of functional T6SS toward overall competitive fitness in various pathogenic Xanthomonas spp. To understand the contribution of T6SS toward ecology and evolution of Xanthomonas spp., we explored the distribution of the three distinguishable T6SS clusters, i3*, i3***, and i4, in approximately 1,740 Xanthomonas genomes, along with their conservation, genetic organization, and their evolutionary patterns in this genus. Screening genomes for core genes of each T6 cluster indicated that 40% of the sequenced strains possess two T6 clusters, with combinations of i3*** and i3* or i3*** and i4. A few strains of Xanthomonas citri, Xanthomonas phaseoli, and Xanthomonas cissicola were the exception, possessing a unique combination of i3* and i4. The findings also indicated clade-specific distribution of T6SS clusters. Phylogenetic analysis demonstrated that T6SS clusters i3* and i3*** were probably acquired by the ancestor of the genus Xanthomonas, followed by gain or loss of individual clusters upon diversification into subsequent clades. T6 i4 cluster has been acquired in recent independent events by group 2 xanthomonads followed by its spread via horizontal dissemination across distinct clades across groups 1 and 2 xanthomonads. We also noted reshuffling of the entire core T6 loci, as well as T6SS spike complex components, hcp and vgrG, among different species. Our findings indicate that gain or loss events of specific T6SS clusters across Xanthomonas phylogeny have not been random.

Nullomers and nullpeptides are short DNA or amino acid sequences that are absent from a genome or proteome, respectively. One potential cause for their absence could be their having a detrimental impact on an organism. RESULTS: Here, we identify all possible nullomers and nullpeptides in the genomes and proteomes of thirty eukaryotes and demonstrate that a significant proportion of these sequences are under negative selection. We also identify nullomers that are unique to specific functional categories: coding sequences, exons, introns, 5'UTR, 3'UTR, promoters, and show that coding sequence and promoter nullomers are most likely to be selected against. By analyzing all protein sequences across the tree of life, we further identify 36,081 peptides up to six amino acids in length that do not exist in any known organism, termed primes. We next characterize all possible single base pair mutations that can lead to the appearance of a nullomer in the human genome, observing a significantly higher number of mutations than expected by chance for specific nullomer sequences in transposable elements, likely due to their suppression. We also annotate nullomers that appear due to naturally occurring variants and show that a subset of them can be used to distinguish between different human populations. Analysis of nullomers and nullpeptides across vertebrate evolution shows they can also be used as phylogenetic classifiers. CONCLUSIONS: We provide a catalog of nullomers and nullpeptides in distinct functional categories, develop methods to systematically study them, and highlight the use of variability in these sequences in other analyses.

Phylogenetic trees can be built from B cell receptor (BCR) sequences and used to study somatic hypermutation and selection. The unique biology of B cells has led to the development of B cell-specific phylogenetic methods. Single-cell sequencing can improve tree building with paired heavy and light chain sequences and (potentially) with associated transcriptomic information. Phylogenetic trees can be used to study B cell migration, differentiation, and evolution over time, but more work is needed to study these processes in a model-based manner. Phylogenetic trees built from B cell receptor (BCR) sequences can trace the history of mutation and selection in B cell clones. Advances in single-cell sequencing can significantly improve all aspects of B cell tree building. Further, there is potential for new methods using single-cell data to drive exciting advances in tracking cellular migration, differentiation, and evolution over time. The widespread availability of single-cell RNA sequencing (scRNA-seq) has led to the development of new methods for understanding immune responses. Single-cell transcriptome data can now be paired with B cell receptor (BCR) sequences. However, RNA from BCRs cannot be analyzed like most other genes because BCRs are genetically diverse within individuals. In humans, BCRs are shaped through recombination followed by mutation and selection for antigen binding. As these processes co-occur with cell division, B cells can be studied using phylogenetic trees representing the mutations within a clone. B cell trees can link experimental timepoints, tissues, or cellular subtypes. Here, we review the current state and potential of how B cell phylogenetics can be combined with single-cell data to understand immune responses. [ABSTRACT FROM AUTHOR]

Eukaryotrophic protists are ecologically significant and possess characteristics key to understanding the evolution of eukaryotes; however, they remain poorly studied, due partly to the complexities of maintaining predator–prey cultures. Kaonashia insperata, gen. nov., et sp. nov., is a free‐swimming biflagellated eukaryotroph with a conspicuous ventral groove, a trait observed in distantly related lineages across eukaryote diversity. Di‐eukaryotic (predator–prey) cultures of K. insperata with three marine algae (Isochrysis galbana, Guillardia theta, and Phaeodactylum tricornutum) were established by single‐cell isolation. Growth trials showed that the studied K. insperata clone grew particularly well on G. theta, reaching a peak abundance of 1.0 × 105 ± 4.0 × 104 cells ml−1. Small‐subunit ribosomal DNA phylogenies infer that K. insperata is a stramenopile with moderate support; however, it does not fall within any well‐defined phylogenetic group, including environmental sequence clades (e.g. MASTs), and its specific placement remains unresolved. Electron microscopy shows traits consistent with stramenopile affinity, including mastigonemes on the anterior flagellum and tubular mitochondrial cristae. Kaonashia insperata may represent a novel major lineage within stramenopiles, and be important for understanding the evolutionary history of the group. While heterotrophic stramenopile flagellates are considered to be predominantly bacterivorous, eukaryotrophy may be relatively widespread amongst this assemblage. [ABSTRACT FROM AUTHOR]

Peste des petits ruminants virus (PPRV) causes a highly infectious disease affecting mainly goats and sheep in large parts of Africa, Asia, and the Middle East and has an important impact on the global economy and food security. Full genome sequencing of PPRV strains has proved to be critical to increasing our understanding of PPR epidemiology and to inform the ongoing global efforts for its eradication. However, the number of full PPRV genomes published is still limited and with a heavy bias towards recent samples and genetic Lineage IV (LIV), which is only one of the four existing PPRV lineages. Here, we generated genome sequences for twenty-five recent (2010–6) and seven historical (1972–99) PPRV samples, focusing mainly on Lineage II (LII) in West Africa. This provided the first opportunity to compare the evolutionary pressures and history between the globally dominant PPRV genetic LIV and LII, which is endemic in West Africa. Phylogenomic analysis showed that the relationship between PPRV LII strains was complex and supported the extensive transboundary circulation of the virus within West Africa. In contrast, LIV sequences were clearly separated per region, with strains from West and Central Africa branched as a sister clade to all other LIV sequences, suggesting that this lineage also has an African origin. Estimates of the time to the most recent common ancestor place the divergence of modern LII and LIV strains in the 1960s–80s, suggesting that this period was particularly important for the diversification and spread of PPRV globally. Phylogenetic relationships among historical samples from LI, LII, and LIII and with more recent samples point towards a high genetic diversity for all these lineages in Africa until the 1970s–80s and possible bottleneck events shaping PPRV's evolution during this period. Molecular evolution analyses show that strains belonging to LII and LIV have evolved under different selection pressures. Differences in codon usage and adaptative selection pressures were observed in all viral genes between the two lineages. Our results confirm that comparative genomic analyses can provide new insights into PPRV's evolutionary history and molecular epidemiology. However, PPRV genome sequencing efforts must be ramped up to increase the resolution of such studies for their use in the development of efficient PPR control and surveillance strategies. [ABSTRACT FROM AUTHOR]

Mpox is an emerging zoonotic disease which has now spread to over 113 countries as of August 2023, with over 89,500 confirmed human cases. The Netherlands had one of the highest incidence rates in Europe during the peak of the outbreak. In this study, we generated 158 near‐complete mpox virus (MPXV) genomes (12.4% of nationwide cases) that were collected throughout the Netherlands from the start of the outbreak in May 2022 to August 2023 to track viral evolution and investigate outbreak dynamics. We detected 14 different viral lineages, suggesting multiple introductions followed by rapid initial spread within the country. The estimated evolutionary rate was relatively high compared to previously described in orthopoxvirus literature, with an estimated 11.58 mutations per year. Genomic rearrangement events occurred at a rate of 0.63% and featured a large deletion event. In addition, based on phylogenetics, we identified multiple potential transmission clusters which could be supported by direct source‐ and contact tracing data. This led to the identification of at least two main transmission locations at the beginning of the outbreak. We conclude that whole genome sequencing of MPXV is essential to enhance our understanding of outbreak dynamics and evolution of a relatively understudied and emerging zoonotic pathogen. [ABSTRACT FROM AUTHOR]

Abstract Background The origins of all major living reptile clades, including the one leading to birds, lie in the Triassic. Following the largest mass extinction in Earth’s history at the end of the Permian, the earliest definite members of the three major living reptile clades, the turtles (Testudines), crocodylians and birds (Archosauria), and lizards, snakes, amphisbaenians, and Tuatara (Lepidosauria) appeared. Recent analyses of the Triassic reptile fossil record suggest that the earliest diversifications in all three of these clades were tightly controlled by abrupt paleoclimate fluctuations and concordant environmental changes. Yet, this has only been preliminarily tested using information from evolutionary trees. Phytosauria consists of superficially crocodylian-like archosaurs that either form the sister to the crown or are the earliest divergence on the crocodylian stem and are present throughout the Triassic, making this clade an excellent test case for examining this biogeographic hypothesis. Results Here, I describe a new phytosaur, Jupijkam paleofluvialis gen. et sp. nov., from the Late Triassic of Nova Scotia, Canada, which at that time sat in northern Pangaea near the northern terminus of the great central Pangean rift. As one of the northernmost occurrences of Phytosauria, J. paleofluvialis provides critical new biogeographic data that enables revised estimations of phytosaur historical biogeography along phylogenies of this clade built under multiple methodologies. Reconstructions of phytosaur historical biogeography based on different phylogenies and biogeographic models suggest that phytosaurs originated in northern Pangaea, spread southward, and then dispersed back northward at least once more during the Late Triassic. Conclusions The results presented in this study link phytosaur biogeography to major changes to Triassic global climate and aridity. Together with the earliest dinosaurs and several other reptile lineages, phytosaur diversification and migration appear to have been restricted by the formation and loss of arid belts across the Pangean supercontinent.

Abstract The availability of phylogenetic data has greatly expanded in recent years. As a result, a new era in phylogenetic analysis is dawning—one in which the methods we use to analyse and assess our data are the bottleneck to producing valuable phylogenetic hypotheses, rather than the need to acquire more data. This makes the ability to accurately appraise and evaluate new methods of phylogenetic analysis and phylogenetic artefact identification more important than ever. Incongruence in phylogenetic reconstructions based on different datasets may be due to two major sources: biological and methodological. Biological sources comprise processes like horizontal gene transfer, hybridization and incomplete lineage sorting, while methodological ones contain falsely assigned data or violations of the assumptions of the underlying model. While the former provides interesting insights into the evolutionary history of the investigated groups, the latter should be avoided or minimized as best as possible. However, errors introduced by methodology must first be excluded or minimized to be able to conclude that biological sources are the cause. Fortunately, a variety of useful tools exist to help detect such misassignments and model violations and to apply ameliorating measurements. Still, the number of methods and their theoretical underpinning can be overwhelming and opaque. Here, we present a practical and comprehensive review of recent developments in techniques to detect artefacts arising from model violations and poorly assigned data. The advantages and disadvantages of the different methods to detect such misleading signals in phylogenetic reconstructions are also discussed. As there is no one‐size‐fits‐all solution, this review can serve as a guide in choosing the most appropriate detection methods depending on both the actual dataset and the computational power available to the researcher. Ultimately, this informed selection will have a positive impact on the broader field, allowing us to better understand the evolutionary history of the group of interest.

Calcium (Ca2 +) homeostasis is essential in conducting various cellular processes including nerve transmission, muscular movement, and immune response. Changes in Ca2 + concentration in the cytoplasm are significant in bringing about various immune responses such as pathogen clearance and apoptosis. Various key players are involved in calcium homeostasis such as calcium binders, pumps, and channels. Sequence-based evolutionary information has recently been exploited to predict the biophysical behaviors of proteins, giving critical clues about their functionality. Ion channels are reportedly the first channels developed during evolution. Calcium homeostasis modulator protein 6 (CALHM6) is one such channel. Comprised of a single domain called Ca_hom_mod, CALHM6 is a stable protein interacting with various other proteins in calcium regulation. No previous attempt has been made to trace the exact evolutionary events in the domain of CALHM6, leaving plenty of room for exploring its evolution across a wide range of organisms. The current study aims to answer the questions by employing a computational-based strategy that used profile Hidden Markov Models (HMMs) to scan for the CALHM6 domain, integrated the data with a time-calibrated phylogenetic tree using BEAST and Mesquite, and visualized through iTOL. Around 4,000 domains were identified, and 14,000 domain gain, loss, and duplication events were observed at the end which also included various protein domains other than CALHM6. The data were analyzed concerning CALHM6 evolution as well as the domain gain, loss, and duplication of its interacting partners: Calpain, Vinculin, protein S100-A7, Thioredoxin, Peroxiredoxin, and Calmodulin-like protein 5. Duplication events of CALHM6 near higher eukaryotes showed its increasing complexity in structure and function. This in-silico phylogenetic approach applied to trace the evolution of CALHM6 was an effective approach to get a better understanding of the protein CALHM6.

Previous work has proposed various mechanisms by which the environment may affect the emergence of linguistic features. For example, dry air may cause careful control of pitch to be more effortful, and so affect the emergence of linguistic distinctions that rely on pitch such as lexical tone or vowel inventories. Criticisms of these proposals point out that there are both historical and geographic confounds that need to be controlled for. We take a causal inference approach to this problem to design the most detailed test of the theory to date. We analyse languages from the Bantu language family, using a prior geographic–phylogenetic tree of relationships to establish where and when languages were spoken. This is combined with estimates of humidity for those times and places, taken from historical climate models. We then estimate the strength of causal relationships in a causal path model, controlling for various influences of inheritance and borrowing. We find no evidence to support the previous claims that humidity affects the emergence of lexical tone. This study shows how using causal inference approaches lets us test complex causal claims about the cultural evolution of language.

Arthropod-borne viruses (arboviruses) comprise a significant and ongoing threat to human health, infecting hundreds of millions annually. Three such arboviruses include circumtropical dengue, Zika, and chikungunya viruses, exhibiting continuous emergence primarily via Aedes mosquito vectors. Nicaragua has experienced endemic dengue virus (DENV) transmission involving multiple serotypes since 1985, with chikungunya virus (CHIKV) reported in 2014–2015, followed by Zika virus (ZIKV) first reported in 2016. In order to identify patterns of genetic variation and selection pressures shaping the evolution of co-circulating DENV serotypes in light of the arrival of CHIKV and ZIKV, we employed whole-genome sequencing on an Illumina MiSeq platform of random-amplified total RNA libraries to characterize 42 DENV low-passage isolates, derived from viremic patients in Nicaragua between 2013 and 2016. Our approach also revealed clinically undetected co-infections with CHIKV. Of the three DENV serotypes (1, 2, and 3) co-circulating during our study, we uncovered distinct patterns of evolution using comparative phylogenetic inference. DENV-1 genetic variation was structured into two distinct co-circulating lineages with no evidence of positive selection in the origins of either lineage, suggesting they are equally fit. In contrast, the evolutionary history of DENV-2 was marked by positive selection, and a unique, divergent lineage correlated with high epidemic potential emerged in 2015 to drive an outbreak in 2016. DENV-3 genetic variation remained unstructured into lineages throughout the period of study. Thus, this study reveals insights into evolutionary and epidemiologic trends exhibited during the circulation of multiple arboviruses in Nicaragua.

A disproportionate number of Greenland's Inuit population are chronically infected with Hepatitis B virus (HBV; 5-10%). HBV genotypes B and D are most prevalent in the circumpolar Arctic. Here, we report 39 novel HBV/D sequences from individuals residing in southwestern Greenland. We performed phylodynamic analyses with ancient HBV DNA calibrators to investigate the origin and relationship of these taxa to other HBV sequences. We inferred a substitution rate of 1.4 × 10-5 [95% HPD 8.8 × 10-6, 2.0 × 10-5] and a time to the most recent common ancestor of 629 CE [95% HPD 37-1138 CE]. The Greenland taxa form a sister clade to HBV/D2 sequences, specifically New Caledonian and Indigenous Taiwanese sequences. The Greenland sequences share amino acid signatures with subgenotypes D1 and D2 and ~97% sequence identity. Our results suggest the classification of these novel sequences does not fit within the current nomenclature. Thus, we propose these taxa be considered a novel quasi-subgenotype.

Markov models of character substitution on phylogenies form the foundation of phylogenetic inference frameworks. Early models made the simplifying assumption that the substitution process is homogeneous over time and across sites in the molecular sequence alignment. While standard practice adopts extensions that accommodate heterogeneity of substitution rates across sites, heterogeneity in the process over time in a site-specific manner remains frequently overlooked. This is problematic, as evolutionary processes that act at the molecular level are highly variable, subjecting different sites to different selective constraints over time, impacting their substitution behavior. We propose incorporating time variability through Markov-modulated models (MMMs), which extend covarion-like models and allow the substitution process (including relative character exchange rates as well as the overall substitution rate) at individual sites to vary across lineages. We implement a general MMM framework in BEAST, a popular Bayesian phylogenetic inference software package, allowing researchers to compose a wide range of MMMs through flexible XML specification. Using examples from bacterial, viral, and plastid genome evolution, we show that MMMs impact phylogenetic tree estimation and can substantially improve model fit compared to standard substitution models. Through simulations, we show that marginal likelihood estimation accurately identifies the generative model and does not systematically prefer the more parameter-rich MMMs. To mitigate the increased computational demands associated with MMMs, our implementation exploits recent developments in BEAGLE, a high-performance computational library for phylogenetic inference. [Bayesian inference; BEAGLE; BEAST; covarion, heterotachy; Markov-modulated models; phylogenetics.].

Background: Taenia solium is a parasite of public health concern, causing human taeniasis and cysticercosis. Two main genotypes have been identified: Asian and African-American. Although characterizing T. solium genotypes is crucial to understanding the genetic epidemiology of its diseases, not much is known about the differences between T. solium mitochondrial genomes from different genotypes. Also, little is known about whether genotypes are further subdivided. Therefore, this study aimed to identify a set of point mutations distributed throughout the T. solium mitochondrial genome that differentiate the African-American from the Asian genotype. Another objective was to identify whether T. solium main genotypes are further stratified. Methods: One Mexican and two Peruvian T. solium mitochondrial genomes were assembled using reads available in the NCBI Sequence Read Archive and the reference genome from China as a template. Mutations with respect to the Chinese reference were identified by multiple genome alignment. Jensen–Shannon and Grantham scores were computed for mutations in protein-coding genes to evaluate whether they affected protein function. Phylogenies by Bayesian inference and haplotype networks were constructed using cytochrome c oxidase subunit 1 and cytochrome b from these genomes and other isolates to infer phylogeographical relationships. Results: A set of 31 novel non-synonymous point mutations present in all genomes of the African-American genotype were identified. These mutations were distributed across the mitochondrial genome, differentiating the African-American from the Asian genotype. All occurred in non-conserved protein positions. Furthermore, the analysis suggested a stratification of the African-American genotypes into an East African and a West African sublineage. Conclusions: A novel set of 31 non-synonymous mutations differentiating the main T. solium genotypes was identified. None of these seem to be causing differences in mitochondrial protein function between parasites of the two genotypes. Furthermore, two sublineages within the African-American genotype are proposed for the first time. The presence of the East African sublineage in the Americas suggests an underestimated connection between East African and Latin American countries that might have arisen in the major slave trade between Portuguese Mozambique and the Americas. The results obtained here help to complete the molecular epidemiology of the parasite. [ABSTRACT FROM AUTHOR]

Humanin (HN) is a mitochondrial peptide that is encoded by the MT-RNR2 gene and can be composed of either 21 or 24 amino acids (aa), depending on whether it is expressed in the mitochondria or cytosol, respectively. It has cytoprotective, anti-inflammatory, and antioxidative properties that may involve a systemic normalization of stress-response homeostasis in many cell types. Moreover, HN analogs, such as S14G-humanin, have been synthesized and found to have strong neuroprotective effects. However, we still lack knowledge on the evolution of the MT-RNR2 gene and its cytosol-expressed products in different organisms. Using phylogenetic analysis, we have uncovered the scarcity of nuclear HN sequences in evolution and shown that true mitochondrial HN homologs are not likely to be found in non-vertebrates. Also, analyzing the diversity of HNs we have discovered that S14G substitution is presented among avian HN sequences while 21-aa HN is highly specific to mammals. [ABSTRACT FROM AUTHOR]

Amyloid‐based prions have simple structures, a wide phylogenetic distribution, and a plethora of functions in contemporary organisms, suggesting they may be an ancient phenomenon. However, this hypothesis has yet to be addressed with a systematic, computational, and experimental approach. Here we present a framework to help guide future experimental verification of candidate prions with conserved functions to understand their role in the early stages of evolution and potentially in the origins of life. We identified candidate prions in all high‐quality proteomes available in UniProt computationally, assessed their phylogenomic distributions, and analyzed candidate‐prion functional annotations. Of the 27 980 560 proteins scanned, 228 561 were identified as candidate prions (~0.82%). Among these candidates, there were 84 Gene Ontology (GO) terms conserved across the three domains of life. We found that candidate prions with a possible role in adaptation were particularly well‐represented within this group. We discuss unifying features of candidate prions to elucidate the primeval roles of prions and their associated functions. Candidate prions annotated as transcription factors, DNA binding, and kinases are particularly well suited to generating diverse responses to changes in their environment and could allow for adaptation and population expansion into more diverse environments. We hypothesized that a relationship between these functions and candidate prions could be evolutionarily ancient, even if individual prion domains themselves are not evolutionarily conserved. Candidate prions annotated with these universally occurring functions potentially represent the oldest extant prions on Earth and are therefore excellent experimental targets. [ABSTRACT FROM AUTHOR]