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Collaborative Expression: Transcriptomics of Conus virgo Suggests Contribution of Multiple Secretory Glands to Venom Production
No full textVenomous marine gastropods of the family Conidae are among the most diversifed predators in marine realm—in large due to their complex venoms. Besides being a valuable source of bioactive neuropeptides conotoxins, cone-snails venoms are an excellent model for molecular evolution studies, addressing origin of key innovations. However, these studies are handicapped by scarce current knowledge on the tissues involved in venom production, as it is generally assumed the sole prerogative of the venom gland (VG). The role of other secretory glands that are present in all Conus species (salivary gland, SG) or only in some species (accessory salivary gland, ASG) remains poorly understood. Here, for the frst time, we carry out a detailed analysis of the VG, SG, and ASG transcriptomes in the vermivorous Conus virgo. We detect multiple transcripts clusters in both the SG and ASG, whose annotations imply venom-related functions. Despite the subsets of transcripts highly-expressed in the VG, SG, and ASG being very distinct, SG expresses an L-, and ASG—Cerm08-, and MEFRR- superfamily conotoxins, all previously considered specifc for VG. We corroborate our results with the analysis of published SG and VG transcriptomes from unrelated fsh-hunting C. geographus, and C. striatus, possibly fsh-hunting C. rolani, and worm-hunting Conus quercinus. In spite of low expression levels of conotoxins, some other specifc clusters of putative venom-related peptides are present and may be highly expressed in the SG of these species. Further functional studies are necessary to determine the role that these peptides play in envenomation. In the meantime, our results show importance of routine multi-tissue sampling both for accurate interpretation of tissue-specifc venom composition in cone-snails, and for better understanding origin and evolution of venom peptides genes
Uranium–lead geochronology applied to pyrope garnet with very low concentrations of uranium
No full textCARNIVORA FROM THE EARLY PLEISTOCENE OF GRĂUNCEANU (OLTEŢ RIVER VALLEY, DACIAN BASIN, ROMANIA)
No full textMorphological and molecular characterisation of Tristoma integrum Diesing, 1850 (Monogenea, Capsalidae), including its complete mitogenome
No full textCapsalids are monopisthocotylean monogenean parasites found on the skin and gills of fish. Capsalines (subfamily Capsalinae) are large-sized capsalids, parasitic on highly prized gamefish, and species of Tristoma parasitise only the gills of swordfish (Xiphias gladius). We obtained specimens of Tristoma integrum Diesing, 1850 from swordfish collected off Algeria in the Mediterranean Sea. Here, we describe the specimens, including the key systematics characters of dorsolateral body sclerites. One specimen was used for a next generation sequencing analysis but a part of it, including the sclerites, was mounted on a permanent slide, drawn, and deposited in a curated collection. We characterised the complete mitogenome, the ribosomal cluster (including 18S and 28S) and additional genes such as Elongation factor 1 alpha (EF1α) and Histone 3. We also retrieved molecular information from the host tissue present in the gut of the monogenean and provide the sequence of the complete rRNA cluster of the host, X. gladius. The mitogenome of T. integrum is 13 968 bp in length and codes for 12 protein, 2 rRNA and 22 tRNA. Phylogenies of capsalids were generated from 28S sequences and concatenated mitochondrial protein-coding genes, respectively. In the 28S phylogeny, most subfamilies based on morphology were not found to be monophyletic, but the Capsalinae were monophyletic. In both phylogenies, the closest member to Tristoma spp. was a member of the Capsaloides. In an Appendix, we report the complex nomenclatural history of Tristoma Cuvier, 1817 and its species.Les Capsalidae sont des monogènes Monopisthocotylea parasites de la peau et des branchies des poissons. Les Capsalinae sont des Capsalidae de grande taille qui parasitent les poissons de pêche sportive, très prisés, et les espèces de Tristoma ne parasitent que les branchies de l’espadon (Xiphias gladius). Nous avons obtenu des spécimens de Tristoma integrum Diesing, 1850 à partir d’espadons collectés au large de l’Algérie en Méditerranée. Nous décrivons les spécimens, y compris les caractères systématiques clés des sclérites dorsolatéraux du corps. Un spécimen a été utilisé pour une analyse de séquençage de nouvelle génération, mais une partie de celui-ci, qui comprend des sclérites, a été montée sur une lame permanente, dessinée et déposée dans une collection. Nous avons caractérisé le mitogénome complet, le cluster ribosomal (y compris 18S et 28S) et des gènes supplémentaires tels que le facteur d’élongation 1 alpha (EF1α) et histone 3. Nous avons également récupéré des informations moléculaires à partir du tissu de l’hôte présent dans l’intestin du monogène et fournissons la séquence du cluster d’ARNr complet de l’hôte, X. gladius. Le mitogénome de T. integrum a une longueur de 13 968 pb et code pour 12 gènes de protéines, 2 ARNr et 22 ARNt. Des phylogénies des Capsalidae ont été générées, respectivement à partir des séquences 28S et des gènes codant pour les protéines mitochondriales concaténés. Dans la phylogénie 28S, la plupart des sous-familles basées sur la morphologie n’ont pas été trouvées monophylétiques, à l’exception notable des Capsalinae. Dans les deux phylogénies, les membres les plus proches de Tristoma spp. étaient des espèces de Capsaloides. Dans une annexe, nous rapportons l’histoire nomenclaturale complexe de Tristoma Cuvier, 1817 et de ses espèces
Fish tissue conversion factors for mercury, cadmium, lead and nine per- and polyfluoroalkyl substances for use within contaminant monitoring
No full textFish tissue levels have to comply with environmental quality standards (EQSs) within the European Water Framework Directive. However, within monitoring, contaminants are sometimes measured in a different tissue than the tissue for which the environmental (whole fish) or human (fillet (equivalent to muscle tissue)) quality standard is set. Tissue conversion factors (k), describing the relationship between concentrations in different tissues, can be used to obtain a quality standard for the appropriate tissue. Several different approaches have been suggested for the calculation of k. For monitoring purposes, we propose the use of a simple, easy reproducible approach that assumes proportionality between two tissue, or tissue and whole fish, concentrations. This allows for an easy comparison of studies and adoption of ks into independent monitoring programs. Here, we determined ks for three metals (mercury (Hg), lead (Pb), cadmium (Cd)) and nine per- and polyfluoroalkyl substances (PFAS) including perfluorooctanesulfonic acid (PFOS) across six marine and freshwater fish species from Northern European lakes and the Baltic Sea. We found significant species differences for Hg for kmuscle/whole fish, for Cd and Pb for kliver/whole fish and for Cd for kliver/muscle. For perfluoroalkyl carboxylic acids (PFCA), we found a chain length dependence with lowest kliver/muscle at low and high chain lengths (C8, C13) and highest for median chain lengths (C9-C12). Further, there were differences between fish species with kliver/muscle for PFOS almost doubling from eelpout (10.3) to herring (19.2) and increasing up to a factor 4 between eelpout and herring for other PFASs. FOSA had two distinctive groups, herring with a kliver/muscle of 48.7 and a second group with ks of 2.3 to 5.9 for all other fish species. Our results suggest that differences in the tissue somatic index, and contaminant uptake, tissue transfer and metabolism result in the need for species-specific ks within monitorin
Co-exposure to highly allergenic airborne pollen and fungal spores in Europe
No full textThe study is aimed at determining the potential spatiotemporal risk of the co-occurrence of airborne pollen and fungal spores high concentrations in different bio-climatic zones in Europe. Birch, grass, mugwort, ragweed, olive pollen and Alternaria and Cladosporium fungal spores were investigated at 16 sites in Europe, in 2005–2019. In Central and northern Europe, pollen and fungal spore seasons mainly overlap in June and July, while in South Europe, the highest pollen concentrations occur frequently outside of the spore seasons. In the coldest climate, no allergy thresholds were exceeded simultaneously by two spore or pollen taxa, while in the warmest climate most of the days with at least two pollen taxa exceeding threshold values were observed. The annual air temperature amplitude seems to be the main bioclimatic factor influencing the accumulation of days in which Alternaria and Cladosporium spores simultaneously exceed allergy thresholds. The phenomenon of co-occurrence of airborne allergen concentrations gets increasingly common in Europe and is proposed to be present on other continents, especially in temperate climate
Evolutionary ecomorphology for the twenty-first century: examples from mammalian carnivores
No full textCarnivores (cats, dogs and kin) are a diverse group of mammals that inhabit a remarkable range of ecological niches. While the relationship between ecology and morphology has long been of interest in carnivorans, the application of quantitative techniques has resulted in a recent explosion of work in the field. Therefore, they provide a case study of how quantitative techniques, such as geometric morphometrics (GMM), have impacted our ability to tease apart complex ecological signals from skeletal anatomy, and the implications for our understanding of the relationships between form, function and ecological specialization. This review provides a synthesis of current research on carnivoran ecomorphology, with the goal of illustrating the complex interaction between ecology and morphology in the skeleton. We explore the ecomorphological diversity across major carnivoran lineages and anatomical systems. We examine cranial elements (skull, sensory systems) and postcranial elements (limbs, vertebral column) to reveal mosaic patterns of adaptation related to feeding and hunting strategies, locomotion and habitat preference. We highlight the crucial role that new approaches have played in advancing our understanding of carnivoran ecomorphology, while addressing challenges that remain in the field, such as ecological classifications, form–function relationships and multi-element analysis, offering new avenues for future research.This work was supported by the Royal Society (RF\ERE\210253to K.E.J.), which funded J.A.S.</p
End-Permian marine ecosystem collapse was a direct consequence of deforestation: Evidence from the Kockatea Shale of the Perth Basin, Western Australia
No full textThe end-Permian mass extinction event resulted in devastated continental biomes, desolated land, and toxic waters. Anoxia led to widespread extinctions in marine ecosystems, affecting most oceanic clades. In this paper, the palynofacies of the marine Kockatea Shale, Western Australia, was studied in drill cores Hovea-3 and Redback-2, with the aim of linking changes in the marine and continental realms across the Permian–Triassic boundary interval in Australia. We show that the post-extinction ‘Dead Zone’ of the Frazer Beach Member of the Sydney Basin, eastern Australia, whose base is dated to 252.10 ± 0.06 Ma, directly correlates to the lower part of the Kockatea Shale in the Perth Basin, the so-called Inertinitic Interval. We demonstrate that the extinction of Permian Glossopteris forests observed in the Perth Basin had an immediateimpact on the marine faunas due to the massive buildup of organic matter, leading to euxinia in the photic zone and ultimately pushing the marine faunas to an ecological extinction. The last lingering occurrence of marine invertebrates of Permian aspect occur in layers that may tentatively mark the Permian –Triassic boundary, positioned just below the appearance of Triassic floras of the Kraeuselisporites saeptatus Zone (equivalent to the Lunatisporites pellucidus Zone). A striking feature at the base of the Early Triassic Sapropelic Interval of the Hovea Member is the sudden and synchronous appearances of anomalously abundant acritarchs and lycophyte spores, alongside the mass occurrence of the bivalve Claraia, allowing correlation with the rise of the eastern Australian post-extinction pioneer floras in the Early Triassic. This demonstrates a significant lag time between the recovery of the terrestrial versus the marine pioneer biota in high-latitude Gondwana, with a significant delay for the faunal recovery.Funding is acknowledged from The Knut and Alice Wallenberg Foundation, grant KAW 2020.0145, and from the Swedish Research Council VR 2019-4061 (V. Vajda). GRS and SL would like to acknowledge funding support for their research from the University of Wollongong, NSW, Australia and the Australian Research Council (ARC- DP230100323). KG was funded by Australian Research Council for support of a Discovery Outstanding Research Award (DP130100577) and ARC Laureate fellowship (FL210100103).</p
The ‘seed-fern’ Lepidopteris mass-produced the abnormal pollen Ricciisporites during the end-Triassic biotic crisis
No full textThe end-Triassic mass extinction (ETE; ~201.6 million years ago) led to dramatic changes in terrestrial eco systems including the extinction of several seed-plant groups. Among the most intriguing features in the vege tation signal is the dominance of the peculiar pollen, Ricciisporites tuberculatus Lundblad, across large areas of the Northern Hemisphere immediately prior to and during the ETE. The parent plant of this pollen has remained unknown for 70 years. Here, we demonstrate that the ‘seed-fern’ Lepidopteris ottonis (Go¨ppert) Schimper (Pel taspermales) produced R. tuberculatus in permanent tetrads. We show that R. tuberculatus is a large, abnormal form of the small smooth-walled monosulcate pollen traditionally associated with L. ottonis, which disappeared at the ETE, when volcanism induced cold-spells followed by global warming. We argue that the production of aberrant R. tuberculatus resulted from ecological pressure in stressed environments that favoured asexual reproduction in peltasperms. The expansion of dry environments led to the dominance of drought-tolerant plants in the Early Jurassic of northern middle latitudes