scholarly journals Some like it hot: population-specific adaptations in venom production to abiotic stressors in a widely distributed cnidarian

BMC Biology ◽  
2020 ◽  
Vol 18 (1) ◽  
Author(s):  
Maria Y. Sachkova ◽  
Jason Macrander ◽  
Joachim M. Surm ◽  
Reuven Aharoni ◽  
Shelcie S. Menard-Harvey ◽  
...  

Abstract Background In cnidarians, antagonistic interactions with predators and prey are mediated by their venom, whose synthesis may be metabolically expensive. The potentially high cost of venom production has been hypothesized to drive population-specific variation in venom expression due to differences in abiotic conditions. However, the effects of environmental factors on venom production have been rarely demonstrated in animals. Here, we explore the impact of specific abiotic stresses on venom production of distinct populations of the sea anemone Nematostella vectensis (Actiniaria, Cnidaria) inhabiting estuaries over a broad geographic range where environmental conditions such as temperatures and salinity vary widely. Results We challenged Nematostella polyps with heat, salinity, UV light stressors, and a combination of all three factors to determine how abiotic stressors impact toxin expression for individuals collected across this species’ range. Transcriptomics and proteomics revealed that the highly abundant toxin Nv1 was the most downregulated gene under heat stress conditions in multiple populations. Physiological measurements demonstrated that venom is metabolically costly to produce. Strikingly, under a range of abiotic stressors, individuals from different geographic locations along this latitudinal cline modulate differently their venom production levels. Conclusions We demonstrate that abiotic stress results in venom regulation in Nematostella. Together with anecdotal observations from other cnidarian species, our results suggest this might be a universal phenomenon in Cnidaria. The decrease in venom production under stress conditions across species coupled with the evidence for its high metabolic cost in Nematostella suggests downregulation of venom production under certain conditions may be highly advantageous and adaptive. Furthermore, our results point towards local adaptation of this mechanism in Nematostella populations along a latitudinal cline, possibly resulting from distinct genetics and significant environmental differences between their habitats.

Author(s):  
Maria Y. Sachkova ◽  
Jason Macrander ◽  
Joachim M. Surm ◽  
Reuven Aharoni ◽  
Shelcie S. Menard-Harvey ◽  
...  

AbstractNematostella vectensis is a sea anemone (Actiniaria, Cnidaria) inhabiting estuaries over a broad geographic range where environmental conditions such as temperatures and salinity vary widely. In cnidarians, antagonistic interactions with predators and prey are mediated by their venom, which may be metabolically expensive. In this study, we challenged Nematostella polyps with heat, salinity, UV light stressors and a combination of all three to determine how abiotic stressors impact toxin expression for individuals collected across this species’ range. Transcriptomics and proteomics revealed that the highly abundant toxin Nv1 was the most downregulated gene under heat stress conditions in multiple populations. Physiological measurements demonstrated that venom is metabolically costly to produce suggesting that downregulating venom expression under stressful conditions may be advantageous. Strikingly, under a range of abiotic stressors, individuals from different geographic locations along this latitudinal cline modulate venom production levels differently in a pattern reflecting local adaptation.


Plants ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 2381
Author(s):  
Rafael Fonseca Benevenuto ◽  
Caroline Bedin Zanatta ◽  
Miguel Pedro Guerra ◽  
Rubens Onofre Nodari ◽  
Sarah Z. Agapito-Tenfen

While some genetically modified (GM) plants have been targeted to confer tolerance to abiotic stressors, transgenes are impacted by abiotic stressors, causing adverse effects on plant physiology and yield. However, routine safety analyses do not assess the response of GM plants under different environmental stress conditions. In the context of climate change, the combination of abiotic stressors is a reality in agroecosystems. Therefore, the aim of this study was to analyze the metabolic cost by assessing the proteomic profiles of GM soybean varieties under glyphosate spraying and water deficit conditions compared to their non-transgenic conventional counterparts. We found evidence of cumulative adverse effects that resulted in the reduction of enzymes involved in carbohydrate metabolism, along with the expression of amino acids and nitrogen metabolic enzymes. Ribosomal metabolism was significantly enriched, particularly the protein families associated with ribosomal complexes L5 and L18. The interaction network map showed that the affected module representing the ribosome pathway interacts strongly with other important proteins, such as the chloro-plastic gamma ATP synthase subunit. Combined, these findings provide clear evidence for increasing the metabolic costs of GM soybean plants in response to the accumulation of stress factors. First, alterations in the ribosome pathway indicate that the GM plant itself carries a metabolic burden associated with the biosynthesis of proteins as effects of genetic transformation. GM plants also showed an imbalance in energy demand and production under controlled conditions, which was increased under drought conditions. Identifying the consequences of altered metabolism related to the interaction between plant transgene stress responses allows us to understand the possible effects on the ecology and evolution of plants in the medium and long term and the potential interactions with other organisms when these organisms are released in the environment.


Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 158
Author(s):  
Colin Eady

For 30 years, forage ryegrass breeding has known that the germplasm may contain a maternally inherited symbiotic Epichloë endophyte. These endophytes produce a suite of secondary alkaloid compounds, dependent upon strain. Many produce ergot and other alkaloids, which are associated with both insect deterrence and livestock health issues. The levels of alkaloids and other endophyte characteristics are influenced by strain, host germplasm, and environmental conditions. Some strains in the right host germplasm can confer an advantage over biotic and abiotic stressors, thus acting as a maternally inherited desirable ‘trait’. Through seed production, these mutualistic endophytes do not transmit into 100% of the crop seed and are less vigorous than the grass seed itself. This causes stability and longevity issues for seed production and storage should the ‘trait’ be desired in the germplasm. This makes understanding the precise nature of the relationship vitally important to the plant breeder. These Epichloë endophytes cannot be ‘bred’ in the conventional sense, as they are asexual. Instead, the breeder may modulate endophyte characteristics through selection of host germplasm, a sort of breeding by proxy. This article explores, from a forage seed company perspective, the issues that endophyte characteristics and breeding them by proxy have on ryegrass breeding, and outlines the methods used to assess the ‘trait’, and the application of these through the breeding, production, and deployment processes. Finally, this article investigates opportunities for enhancing the utilisation of alkaloid-producing endophytes within pastures, with a focus on balancing alkaloid levels to further enhance pest deterrence and improving livestock outcomes.


2021 ◽  
Author(s):  
Rabiatou A. Diarra ◽  
Mohamed M. Traore ◽  
Amy M Junnila ◽  
Sekou F. Traore ◽  
Seydou Doumbia ◽  
...  

Abstract Background Attractive Toxic Sugar Baits (ATSBs) successfully reduced Anopheles mosquito vector populations and malaria parasite transmission in Mali, but application methods need to be improved for wide-scale use, and effects on non-target organisms (NTOs) must be assessed. The goals of this study were to determine on a village level the effect of different outdoor configurations of ATSB bait stations to 1) achieve > 25% Anopheles mosquito vector daily feeding rate for both males and females and 2) minimize the effect on non-target organisms. Methods Dye was added to Attractive Sugar Bait Stations (ASB – without toxin) to mark mosquitoes feeding on the sugar baits, and CDC UV light traps were used to monitor mosquitoes for the presence of the dye. Yellow plates, pitfall traps, Malaise traps, UV light traps, UV tray traps, and sweep nets were used to trap and sample non-target organisms (NTOs) for dye, indicating feeding on the ASB. ASB stations were hung on outer walls of village homes to determine the impact of different densities of ASBs (1,2, or 3 per home) as well as the impact of ASB height (1 m or 1.8 m above the ground on sugar feeding by anophelines. These experiments were carried out separately, on consecutive nights for mosquito and NTO monitoring. Eight villages in the Koulikoro province were chosen as the experimental locations. Results The use of one ASB station per house marked 23.11% of female and 7.11% of male An. gambiae s.l. While two and three ASB stations per house gave feeding rates above the 25% goal, there was no statistical difference in the percentage of marked mosquitoes (p=0.3141 females; p=0.9336 males). There was no difference in sugar feeding on ASB stations when hung at 1.0 and 1.8 m and (p=0.5170 females; p=0.9934 males); however, ASBs at 1.8 m had less accidental damage from village residents and animals, and subsequent invasion of non-targets through rips or holes produced. ASB stations at 1.8 m above ground were fed on by three of seven monitored insect orders. Feeding rates were less than 0.015% of total trap catches and as low as 0.0001%. The monitored orders were: Hymenoptera [ants (Formicidae), bees (Apidae), and wasps (Vespidae)], Lepidoptera (Rhopalocera, Bombyces, Geometroidea, Noctuoidea, Sphingidae, Pyraloidea), Coleoptera (Carabidae, Tenebrionidae, Scarabaeidae, Cerambycidae, and Chrysomelidae), Diptera (Brachycera, Chironomidae), Hemiptera (Cicadomorpha and Heteroptera), Neuroptera (Myrmeleontiformia) and Orthoptera (Caelifera and Ensifera). Using one or two stations limited evidence of NTO feeding to ants (Hymenoptera), Brachycera, Heteroptera, Noctuiodea, Rhopalocera, wasps (Vespidae) and wild bees (Apidae) (both Hymenoptera) and had a significantly reduced percentage of stained individuals compared to three stations which had the highest feeding rates amongst NTOs. The percentages of stained individuals were as follows: 6.84 ± 2.03% Brachycera were stained followed by wasps (Hymenoptera: Vespidae) 5.32 ± 2.27%, and Rhopalocera 2.22 ± 1.79%. Hanging the optimal number of stations per house for catching mosquitoes (two) 1.8 m above ground, limited the groups of non-targets to Brachycera, Chironomidae, Noctuoidea, Rhopalocera, parasitic wasps and wasps (both Hymenoptera: Vespidae). The three most commonly stained non-target insect groups at this height were wasps (Vespidae) (1.65 ± 0.75%), Chironomidae (0.99 ± 0.37), and Brachycera (1.55 ± 0.69%). Feeding at this height only occurred when stations were damaged.Conclusions The goal of marking one quarter of the total Anopheles mosquito vector population per day was obtained using 2 bait stations at 1.8 m height above the ground on the outer walls of houses. This configuration of ATSB stations also had minimal effects on non-target insects: only 0.0001% to 0.013% of specimens (in three orders) were marked. Stations hung 1.8 m above the ground had less accidental damage from passing people and livestock. The minimal marking of non-target insects may be attributed to visual orientation of non-mosquito insects while mosquitoes, are mostly guided by olfactory cues. Furthermore, the bait stations have a membrane cover, which if intact, is impenetrable to most sugar feeding non-target insects but is pierced by the stylets of the mosquito proboscis. Thus, most non-target insects are not exposed to the toxin even if they approach the bait stations.


2016 ◽  
Vol 79 (1) ◽  
pp. 1-16 ◽  
Author(s):  
Charlotte Ann Roberts

Abstract This paper considers the discipline of palaeopathology, how it has developed, how it is studied, and what limitations present challenges to analysis. The study of disease has a long history and has probably most rapidly developed over the last 40-50 years with the development of methods, and particularly ancient pathogen DNA analysis. While emphasizing that palaeopathology has close synergies to evolutionary medicine, it focuses then on three ‘case studies’ that illustrate the close interaction people have had with their environments and how that has impacted their health. Upper and lower respiratory tract disease has affected sinuses and ribs, particularly in urban contexts, and tuberculosis in particular has been an ever present disease throughout thousands of years of our existence. Ancient DNA methods are now allowing us to explore how strains of the bacteria causing TB have changed through time. Vitamin D deficiency and ‘phossy jaw’ are also described, both potentially related to polluted environments, and possibly to working conditions in the industrial period. Access to UV light is emphasized as a preventative factor for rickets and where a person lives is important (latitude). The painful stigmatizing ‘phossy jaw’ appears to be a condition related to the match making industries. Finally, thoughts for the future are outlined, and two key concerns: a close consideration of ethical issues and human remains, especially with destructive analyses, and thinking more about how palaeopathological research can impact people beyond academia.


1994 ◽  
Vol 358 ◽  
Author(s):  
P. Steiner ◽  
F. Kozlowski ◽  
W. Lang

ABSTRACTIndium, tin, antimony and aluminum are deposited by an electrochemical process into the pores of n-type porous silicon which is anodized with ultraviolet light applied during formation. The presence of these metal atoms in the porous layer is checked by electron microprobe measurement. As reported previously, UV-light etched material shows red photoluminescence (630 nm) and blue electroluminescence (470 nm) without the metal treatment. After metal deposition the photoluminescence intensity decreases slightly (factor 0.5 - 0.8), whereas the spectral position remains constant. The electroluminescence efficiency is significantly enhanced by indium, aluminum and tin in the pores (factor 5 - 90). The tin and antimony treatment causes a red shift to 580 nm and 740 nm, respectively. The conductivity is slightly increased by all kinds of metals by a factor 2-5.


Author(s):  
Asma Ul Hosna Meem ◽  
Kyle Rudolph ◽  
Allyson Cox ◽  
Austin Andwan ◽  
Timothy Osborn ◽  
...  

Abstract Digital light processing (DLP) is an emerging vatphotopolymerization-based 3D-printing technology where full layers of photosensitive resin are irradiated and cured with projected ultraviolet (UV) light to create a three-dimensional part layer-by-layer. Recent breakthroughs in polymer chemistry have led to a growing number of UV-curable elastomeric photoresins developed exclusively for vat photopolymerization additive manufacturing (AM). Coupled with the practical manufacturing advantages of DLP AM (e.g., industry-leading print speeds and sub-micron-level print resolution), these novel elastomeric photoresins are compelling candidates for emerging applications requiring extreme flexibility, stretchability, conformability, and mechanically-tunable stiffness (e.g., soft robotic actuators and stretchable electronics). To advance the role of DLP AM in these novel and promising technological spaces, a fundamental understanding of the impact of DLP manufacturing process parameters on mechanical properties is requisite. This paper highlights our recent efforts to explore the process-property relationship for ELAST-BLK 10, a new commercially-available UV-curable elastomer for DLP AM. A full factorial design of experiments is used to investigate the effect of build orientation and layer thickness on the quasi-static tensile properties (i.e., small-strain elastic modulus, ultimate tensile strength, and elongation at fracture) of ELAST-BLK 10. Statistical results, based on a general linear model via ANOVA methods, indicate that specimens with a flat build orientation exhibit the highest elastic modulus, ultimate tensile strength, and elongation at fracture, likely due to a larger surface area that enhances crosslink density during the curing process. Several popular hyperelastic constitutive models (e.g., Mooney-Rivlin, Yeoh, and Gent) are calibrated to our quasi-static tensile data to facilitate component-level predictive analyses (e.g., finite-element modeling) of soft robotic actuators and other emerging soft-matter applications.


2020 ◽  
Vol 125 (6) ◽  
pp. 955-967 ◽  
Author(s):  
Mireia Gomez-Gallego ◽  
Nari Williams ◽  
Sebastian Leuzinger ◽  
Peter Matthew Scott ◽  
Martin Karl-Friedrich Bader

Abstract Background and Aims Biotic and abiotic stressors can cause different defoliation patterns within trees. Foliar pathogens of conifers commonly prefer older needles and infection with defoliation that progresses from the bottom crown to the top. The functional role of the lower crown of trees is a key question to address the impact of defoliation caused by foliar pathogens. Methods A 2 year artificial defoliation experiment was performed using two genotypes of grafted Pinus radiata to investigate the effects of lower-crown defoliation on carbon (C) assimilation and allocation. Grafts received one of the following treatments in consecutive years: control–control, control–defoliated, defoliated–control and defoliated–defoliated. Results No upregulation of photosynthesis either biochemically or through stomatal control was observed in response to defoliation. The root:shoot ratio and leaf mass were not affected by any treatment, suggesting prioritization of crown regrowth following defoliation. In genotype B, defoliation appeared to impose C shortage and caused reduced above-ground growth and sugar storage in roots, while in genotype A, neither growth nor storage was altered. Root C storage in genotype B decreased only transiently and recovered over the second growing season. Conclusions In genotype A, the contribution of the lower crown to the whole-tree C uptake appears to be negligible, presumably conferring resilience to foliar pathogens affecting the lower crown. Our results suggest that there is no C limitation after lower-crown defoliation in P. radiata grafts. Further, our findings imply genotype-specific defoliation tolerance in P. radiata.


Crystals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 817
Author(s):  
Asad Syed ◽  
Lakshmi Sagar Reddy Yadav ◽  
Ali H. Bahkali ◽  
Abdallah M. Elgorban ◽  
Deshmukh Abdul Hakeem ◽  
...  

The impact of a CeO2-ZnO nanocomposite on the photocatalytic and antibacterial properties compared to bare ZnO was investigated. A CeO2-ZnO nanocomposite was synthesized using Acacia nilotica fruit extract as a novel fuel by a simple solution combustion method. The obtained CeO2-ZnO nanocomposite was confirmed structurally by XRD, FTIR, Raman and UV-DRS and morphologically by SEM/TEM analysis. The XRD pattern indicates the presence of both hexagonal Wurtzite-structured ZnO (major) and cubic-phase CeO2 (minor). FTIR shows the presence of a Ce-O-Ce vibration at 468 cm−1 and Zn-O vibration at 445 cm−1. The existence of a band at 460 cm−1 confirmed the F2g Raman-active mode of the fluorite cubic crystalline structure for CeO2. Diffused reflectance spectroscopy was used to estimate the bandgap (Eg) from Kubelka–Munk (K–M) theory which was found to be 3.4 eV. TEM analysis shows almost spherical-shaped particles, at a size of about 10–15 nm. The CeO2-ZnO nanocomposite shows a good BET specific surface area of 30 m2g−1. The surface defects and porosity of the CeO2-ZnO nanocomposite caused methylene blue (MB) dye to degrade under sunlight (88%) and UV light (92%). The CeO2-ZnO nanocomposite also exhibited considerable antibacterial activity against a pathogenic bacterial strain.


Sign in / Sign up

Export Citation Format

Share Document