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Venomics of Remipede Crustaceans Reveals Novel Peptide Diversity and Illuminates the Venom’s Biological Role
No full textWe report the first integrated proteomic and transcriptomic investigation of a crustacean venom. Remipede crustaceans are the venomous sister group of hexapods, and the venom glands of the remipede Xibalbanus tulumensis express a considerably more complex cocktail of proteins and peptides than previously thought. We identified 32 venom protein families, including 13 novel peptide families that we name xibalbins, four of which lack similarities to any known structural class. Our proteomic data confirm the presence in the venom of 19 of the 32 families. The most highly expressed venom components are serine peptidases, chitinase and six of the xibalbins. The xibalbins represent Inhibitory Cystine Knot peptides (ICK), a double ICK peptide, peptides with a putative Cystine-stabilized α-helix/β-sheet motif, a peptide similar to hairpin-like β-sheet forming antimicrobial peptides, two peptides related to different hormone families, and four peptides with unique structural motifs. Remipede venom components represent the full range of evolutionary recruitment frequencies, from families that have been recruited into many animal venoms (serine peptidases, ICKs), to those having a very narrow taxonomic range (double ICKs), to those unique for remipedes. We discuss the most highly expressed venom components to shed light on their possible functional significance in the predatory and defensive use of remipede venom, and to provide testable ideas for any future bioactivity studies.This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
The one-two punch of plastic exposure: Macro- and micro-plastics induce multi-organ damage in seabirds
No full textPlastic pollution in the world's oceans is ubiquitous and increasing. The environment is inundated with microplastics (< 1 mm), and the health effects of these less conspicuous pollutants is poorly known. In addition, there is now evidence that macroplastics can release microplastics in the form of shedding or digestive fragmentation, meaning there is potential for macroplastic exposure to induce direct and indirect pathology through microplastics. Therefore, there is an urgent need for data from wild populations on the relationship between macro- and microplastic exposure and the potential compounding pathological effects of these forms of plastics. We investigated the presence and impact of microplastics in multiple tissues from Flesh-footed Shearwaters Ardenna carneipes, a species that ingests considerable quantities of plastics, and used histopathological techniques to measure physiological responses and inflammation from the plastics. All organs examined (kidney, spleen, proventriculus) had embedded microplastic particles and this correlated with macroplastic exposure. Considerable tissue damage was recorded, including a significant reduction in tubular glands and rugae in the proventriculus, and evidence of inflammation, fibrosis, and loss of organ structures in the kidney and spleen. This indicates macroplastics can induce damage directly at the site of exposure, while microplastics can be mobilised throughout the body causing widespread pathology. Collectively, these results indicate the scope and severity of the health impacts of plastic pollution may be grossly underestimated.Copyright © 2022 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/) The attached file is the published version of the article.NHM Repositor
Six new species of Handaoia Seyrig, 1952 (Hymenoptera, Ichneumonidae, Phygadeuontinae): the first to be described from the New World
Get PDFHandaoia Seyrig, 1952 is a small genus of Phygadeuontinae currently represented by eleven described species from Madagascar, Tanzania and Europe, and can be recognized by the combination of the distally expanded and ventrally flattened antennal flagellum, complete posterior transverse carina of the mesosternum, isolated ‘pit’ (episternal scrobe) in the mesopleuron, and a single bulla in fore wing vein 2m-cu. Most species have a distinctive combined area basalis and area superomedia on the propodeum. The following six new species from Central and South America are described and illustrated: H. cuscoensis Bordera sp. nov. from Peru, H. fritzi sp. nov. from Brazil, H. mercedensis Bordera sp. nov. from Peru, H. plaumanni sp. nov. from Brazil, H. ruizcancinoi Bordera sp. nov. from Mexico, and H. urceus sp. nov. from Brazil. A key to the New World species is provided.Copyright (c) 2021 Santiago Bordera, Gavin R. Broad. This work is licensed under a Creative Commons Attribution 4.0 International License. The attached file is the published version of the article.NHM Repositor
Hidden Phylogenomic Signal Helps Elucidate Arsenurine Silkmoth Phylogeny and the Evolution of Body Size and Wing Shape Trade-Offs
No full textOne of the key objectives in biological research is understanding how evolutionary processes have produced Earth’s diversity. A critical step toward revealing these processes is an investigation of evolutionary tradeoffs—that is, the opposing pressures of multiple selective forces. For millennia, nocturnal moths have had to balance successful flight, as they search for mates or host plants, with evading bat predators. However, the potential for evolutionary trade-offs between wing shape and body size are poorly understood. In this study, we used phylogenomics and geometric morphometrics to examine the evolution of wing shape in the wild silkmoth subfamily Arsenurinae (Saturniidae) and evaluate potential evolutionary relationships between body size and wing shape. The phylogeny was inferred based on 782 loci from target capture data of 42 arsenurine species representing all 10 recognized genera. After detecting in our data one of the most vexing problems in phylogenetic inference—a region of a tree that possesses short branches and no “support” for relationships (i.e., a polytomy), we looked for hidden phylogenomic signal (i.e., inspecting differing phylogenetic inferences, alternative support values, quartets, and phylogenetic networks) to better illuminate the most probable generic relationships within the subfamily. We found there are putative evolutionary trade-offs between wing shape, body size, and the interaction of fore- and hindwing (HW) shape. Namely, body size tends to decrease with increasing HW length but increases as forewing (FW) shape becomes more complex. Additionally, the type of HW (i.e., tail or no tail) a lineage possesses has a significant effect on the complexity of FW shape. We outline possible selective forces driving the complex HW shapes that make Arsenurinae, and silkmoths as a whole, so charismatic. [Anchored hybrid enrichment; Arsenurinae; geometric morphometrics; Lepidoptera; phylogenomics; Saturniidae.]Copyright © 2021, The Authors. This document is the author’s final accepted version of the journal article. You are advised to consult the published version if you wish to cite from it.NHM Repositor
Revision of the “ Chloritis delibrata (Benson, 1836)” group (Gastropoda, Stylommatophora, Camaenidae)
Get PDFChloritis delibrata (Benson, 1836), known from northeastern India, was believed to have three varietal forms, sometimes mentioned as subspecies: C. delibrata var. khasiensis (Nevill, 1877) and C. delibrata var. fasciata (Godwin-Austen, 1875) from the Khasi Hills, India, and C. delibrata var. procumbens (Gould, 1844) from Dawei in Myanmar. The reproductive anatomy of the latter form is known and does not match with those of any continental camaenid genera, but does with that of the newly examined Chloritis platytropis Möllendorff, 1894 from Thailand. The latter species is conchologically similar to Bouchetcamaena huberi Thach, 2018 (synonym of Helix fouresi Morlet, 1886), which is the type species of the genus Bouchetcamaena Thach, 2018. Thus, Bouchetcamaena can provisionally host the entire Chloritis delibrata -group with the exception of var. fasciata, which is transferred to Burmochloritis Godwin-Austen, 1920 due to the multiple reddish bands on its shell. The examination of shells deposited in the Natural History Museum, London revealed that seven morphologically distinguishable forms are present, which are accepted here as representing distinct species. Four new species are described from India: Bouchetcamaena foveata Páll-Gergely sp. nov., B. fusca Páll-Gergely sp. nov., B. raripila Páll-Gergely sp. nov., and B. subdelibrata Páll-Gergely sp. nov.Copyright Barna Páll-Gergely et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.NHM Repositor
Heterochrony and parallel evolution of echinoderm, hemichordate and cephalochordate internal bars
No full textDeuterostomes comprise three phyla with radically different body plans. Phylogenetic bracketing of the living deuterostome clades suggests the latest common ancestor of echinoderms, hemichordates and chordates was a bilaterally symmetrical worm with pharyngeal openings, with these characters lost in echinoderms. Early fossil echinoderms with pharyngeal openings have been described, but their interpretation is highly controversial. Here, we critically evaluate the evidence for pharyngeal structures (gill bars) in the extinct stylophoran echinoderms Lagynocystis pyramidalis and Jaekelocarpus oklahomensis using virtual models based on high-resolution X-ray tomography scans of three-dimensionally preserved fossil specimens. Multivariate analyses of the size, spacing and arrangement of the internal bars in these fossils indicate they are substantially more similar to gill bars in modern enteropneust hemichordates and cephalochordates than to other internal bar-like structures in fossil blastozoan echinoderms. The close similarity between the internal bars of the stylophorans L. pyramidalis and J. oklahomensis and the gill bars of extant chordates and hemichordates is strong evidence for their homology. Differences between these internal bars and bar-like elements of the respiratory systems in blastozoans suggest these structures might have arisen through parallel evolution across deuterostomes, perhaps underpinned by a common developmental genetic mechanism.© 2022 The Authors. Published by the Royal Society under the terms of the Creative Commons AttributionLicense http://creativecommons.org/licenses/by/4.0/, which permits unrestricted use, provided the originalauthor and source are credited.NHM Repositor
Knowledge, perceptions and practices regarding schistosomiasis among women living in a highly endemic rural district in Zimbabwe: implications on infections among preschool-aged children
Get PDFAbstract
Background
Schistosomiasis primarily affects poor and neglected communities due to their lack of safe water and sanitation facilities. In an effort to improve intervention strategies, the present study investigated the association of socio-demographic characteristics of women with their existing knowledge, perceptions and practices (KPP) in five urogenital schistosomiasis endemic rural communities in Zimbabwe.
Methods
In February 2016, a cross sectional study was conducted in which 426 women in rural Madziwa area, Shamva District were interviewed using a pretested structured questionnaire seeking their KPP and socio-demographic characteristics. Logistic regression analysis was performed to identify socio-demographic factors associated with the KPP variables.
Results
Among the 426 participants, 93.7% knew about schistosomiasis, while 97.7 and 87.5% understood the disease transmission and methods for prevention, respectively. A significantly higher percentage of women aged ≥ 30 years compared to those < 30 years indicated that infertility is a complication of untreated chronic schistosomiasis (OR: 1.7, 95% CI: 0.9–3.0). Compared to women who had no history of infection, those who had been infected before were more likely to think that they were currently infected (OR: 3.7, 95% CI: 2.4–6.0). Bathing in unsafe water sources was more common in non-apostolic compared to apostolic followers (OR: 2.1, 95% CI: 1.2–3.7). Sole use of unsafe water for domestic purposes was significantly higher in uneducated women compared to the educated (OR: 1.8, 95% CI: 1.0–3.1). Compared to women of the Chakondora community, those in Chihuri, Nduna and Kaziro were more likely to know that dysuria is a symptom of schistosomiasis while those in Chihuri were also likely to allow young children to perform water contact activities (OR: 2.9, 95% CI: 1.5–5.5).
Conclusions
Despite the high level of schistosomiasis awareness, some women had inadequate knowledge about the mode of transmission and preventive measures for schistosomiasis. Socio-demographic characteristics were associated with the KPP of women. Thus, disease control efforts should consider socio-demographic factors, which may influence the knowledge, perceptions and practices of occupants in a given setting.Copyright © The Author(s) 2019. This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/ publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article.NHM Repositor
Ancient Hybridization and Adaptive Introgression of an Invadolysin Gene in Schistosome Parasites
Get PDFAbstract - Introgression among parasite species has the potential to transfer traits of biomedical importance across species boundaries. The parasitic blood fluke Schistosoma haematobium causes urogenital schistosomiasis in humans across sub-Saharan Africa. Hybridization with other schistosome species is assumed to occur commonly, because genetic crosses between S. haematobium and livestock schistosomes, including S. bovis, can be staged in the laboratory, and sequencing of mtDNA and rDNA amplified from microscopic miracidia larvae frequently reveals markers from different species. However, the frequency, direction, age, and genomic consequences of hybridization are unknown. We hatched miracidia from eggs and sequenced the exomes from 96 individual S. haematobium miracidia from infected patients from Niger and the Zanzibar archipelago. These data revealed no evidence for contemporary hybridization between S. bovis and S. haematobium in our samples. However, all Nigerien S. haematobium genomes sampled show hybrid ancestry, with 3.3–8.2% of their nuclear genomes derived from S. bovis, providing evidence of an ancient introgression event that occurred at least 108–613 generations ago. Some S. bovis-derived alleles have spread to high frequency or reached fixation and show strong signatures of directional selection; the strongest signal spans a single gene in the invadolysin gene family (Chr. 4). Our results suggest that S. bovis/S. haematobium hybridization occurs rarely but demonstrate profound consequences of ancient introgression from a livestock parasite into the genome of S. haematobium, the most prevalent schistosome species infecting humans.© The Author(s) 2019. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/ licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
Worms and bugs of the gut: the search for diagnostic signatures using barcoding, and metagenomics–metabolomics
No full textAbstract
Gastrointestinal (GI) helminth infections cause significant morbidity in both humans and animals worldwide. Specific and sensitive diagnosis is central to the surveillance of such infections and to determine the effectiveness of treatment strategies used to control them. In this article, we: (i) assess the strengths and limitations of existing methods applied to the diagnosis of GI helminth infections of humans and livestock; (ii) examine high-throughput sequencing approaches, such as targeted molecular barcoding and shotgun sequencing, as tools to define the taxonomic composition of helminth infections; and (iii) discuss the current understanding of the interactions between helminths and microbiota in the host gut. Stool-based diagnostics are likely to serve as an important tool well into the future; improved diagnostics of helminths and their environment in the gut may assist the identification of biomarkers with the potential to define the health/disease status of individuals and populations, and to identify existing or emerging anthelmintic resistance.
Graphical AbstractNHM Repositor
A diversification relay race from Caribbean-Mesoamerica to the Andes: historical biogeography of Xylophanes hawkmoths
Get PDFThe regions of the Andes and Caribbean-Mesoamerica are both hypothesized to be the cradle for many Neotropical lineages, but few studies have fully investigated the dynamics and interactions between Neotropical bioregions. The New World hawkmoth genus Xylophanes is the most taxonomically diverse genus in the Sphingidae, with the highest endemism and richness in the Andes and Caribbean-Mesoamerica. We integrated phylogenomic and DNA barcode data and generated the first time-calibrated tree for this genus, covering 93.8% of the species diversity. We used event-based likelihood ancestral area estimation and biogeographic stochastic mapping to examine the speciation and dispersal dynamics of Xylophanes across bioregions. We also used trait-dependent diversification models to compare speciation and extinction rates of lineages associated with different bioregions. Our results indicate that Xylophanes originated in Caribbean-Mesoamerica in the Late Miocene, and immediately diverged into five major clades. The current species diversity and distribution of Xylophanes can be explained by two consecutive phases. In the first phase, the highest Xylophanes speciation and emigration rates occurred in the Caribbean-Mesoamerica, and the highest immigration rates occurred in the Andes, whereas in the second phase the highest immigration rates were found in Amazonia, and the Andes had the highest speciation and emigration rates.Copyright © 2022, The Authors. This document is the author’s final accepted version of the journal article. You are advised to consult the published version if you wish to cite from it.NHM Repositor