118 research outputs found

    Complete mitochondrial genome of the geniculate calcified red alga, Corallina officinalis (Corallinales, Rhodophyta)

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    peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tmdn20© 2016 The Author(s). Published by Taylor & Francis. 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 use, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published pd

    Evaluation of DNA barcode libraries used in the UK and developing an action plan to fill priority gaps

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    There are approximately 76,000 eukaryote species recognised in the UK, and while we know some of them in great detail, the majority of these species are poorly known, and hundreds of new species are discovered each year. DNA barcoding uses a short, standardised segment of an organism’s genome for identification by comparison to a reference library; however, the UK lags behind several countries in Europe and North America in that we lack trusted, reliable and openly accessible reference sequences for key UK taxa. This report is the first step in rectifying this by engaging diverse stakeholders to facilitate collaboration and coordination; providing robust stakeholder-based and independent assessment of the current state of reference libraries available for all known UK taxa; and prioritising key taxa. A survey was developed and shared with the UK research and end user community, receiving 80 responses from a wide range of stakeholders and covering the focal taxa / assemblages and habitats; the DNA reference libraries in use, their quality assurance and perceived coverage. A formal gap analysis of the public DNA data in major DNA reference libraries highlighted that an estimated 52% of UK species have publicly available DNA data of some sort; however, coverage in gene specific reference libraries varies greatly (eg 2 – 52%), as does the associated quality assurance. Priority taxa highlighted by end users had coverage in reference libraries ranging from almost complete, in the case of known invasive non-native species, to significant coverage (71%) for taxa with conservation designations. However, these data also vary by kingdom and reference library, as does the associated quality assurance. If taking a strict requirement of DNA data provided by UK specimens and held in UK repositories, for robust QC and QA, then the proportion of UK species with public DNA data in reference libraries falls to less than 4% in the largest reference library assessed (BOLD). While standard genes for DNA-based identification have essentially been established, more work is required to establish the priority taxa required for regulatory delivery in contrast to taxa that are surveyed in a non-regulatory framework. Several barriers to the development of barcode libraries were highlighted, the most relevant being sustained large scale funding, expertise, capacity, laboratory skills and equipment, quality control and assurance, collecting logistics (eg permits and access) and communication. Significant opportunities identified include a large network of interested experts, several organisations with significant delivery capabilities, current large-scale projects and funding opportunities, emerging technologies and the economy of scale for DNA sequencing. Following a stakeholder workshop, we have outlined a concise action plan to provide reliable, open access reference sequences, linked to open access vouchers, identified by known experts, to facilitate UK academic and regulatory aims.This report is published by Natural England under the Open Government Licence - OGLv3.0 for public sector information. You are encouraged to use, and reuse, information subject to certain conditions. For details of the licence visit Copyright. Natural England photographs are only available for non-commercial purposes. If any other information such as maps or data cannot be used commercially this will be made clear within the report. ISBN 978-1-78354-671-8 © Natural England and other parties 2020 © Trustees of the Natural History Museum, Londo

    The mitochondrial genome of Parascaris univalens - implications for a “forgotten” parasite

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    © Jabbar et al.; licensee BioMed Central Ltd. 2014 This article is published under license to BioMed Central Ltd. 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 use, distribution, and reproduction in any medium, provided the original work is properly credited. 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 file attached is the Published/publisher’s pdf version of the article

    Metabarcoding unsorted kick‐samples facilitates macroinvertebrate‐based biomonitoring with increased taxonomic resolution, while outperforming environmental DNA

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    Pereira‐da‐Conceicoa, L, Elbrecht, V, Hall, A, Briscoe, A, Barber‐James, H, Price, B. Metabarcoding unsorted kick‐samples facilitates macroinvertebrate‐based biomonitoring with increased taxonomic resolution, while outperforming environmental DNA. Environmental DNA. 2020; 00: 1– 19. https://doi.org/10.1002/edn3.116© 2020 The Authors. Environmental DNA published by John Wiley & Sons Ltd This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. The attached file is the published pdf

    Functional divergence in the role of N-linked glycosylation in smoothened signaling

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    The G protein-coupled receptor (GPCR) Smoothened (Smo) is the requisite signal transducer of the evolutionarily conserved Hedgehog (Hh) pathway. Although aspects of Smo signaling are conserved from Drosophila to vertebrates, significant differences have evolved. These include changes in its active sub-cellular localization, and the ability of vertebrate Smo to induce distinct G protein-dependent and independent signals in response to ligand. Whereas the canonical Smo signal to Gli transcriptional effectors occurs in a G protein-independent manner, its non-canonical signal employs Gαi. Whether vertebrate Smo can selectively bias its signal between these routes is not yet known. N-linked glycosylation is a post-translational modification that can influence GPCR trafficking, ligand responsiveness and signal output. Smo proteins in Drosophila and vertebrate systems harbor N-linked glycans, but their role in Smo signaling has not been established. Herein, we present a comprehensive analysis of Drosophila and murine Smo glycosylation that supports a functional divergence in the contribution of N-linked glycans to signaling. Of the seven predicted glycan acceptor sites in Drosophila Smo, one is essential. Loss of N-glycosylation at this site disrupted Smo trafficking and attenuated its signaling capability. In stark contrast, we found that all four predicted N-glycosylation sites on murine Smo were dispensable for proper trafficking, agonist binding and canonical signal induction. However, the under-glycosylated protein was compromised in its ability to induce a non-canonical signal through Gαi, providing for the first time evidence that Smo can bias its signal and that a post-translational modification can impact this process. As such, we postulate a profound shift in N-glycan function from affecting Smo ER exit in flies to influencing its signal output in mice

    Photoreceptor Spectral Sensitivity in the Bumblebee, Bombus impatiens (Hymenoptera: Apidae)

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    The bumblebee Bombus impatiens is increasingly used as a model in comparative studies of colour vision, or in behavioural studies relying on perceptual discrimination of colour. However, full spectral sensitivity data on the photoreceptor inputs underlying colour vision are not available for B. impatiens. Since most known bee species are trichromatic, with photoreceptor spectral sensitivity peaks in the UV, blue and green regions of the spectrum, data from a related species, where spectral sensitivity measurements have been made, are often applied to B impatiens. Nevertheless, species differences in spectral tuning of equivalent photoreceptor classes may result in peaks that differ by several nm, which may have small but significant effects on colour discrimination ability. We therefore used intracellular recording to measure photoreceptor spectral sensitivity in B. impatiens. Spectral peaks were estimated at 347, 424 and 539 nm for UV, blue and green receptors, respectively, suggesting that this species is a UV-blue-green trichromat. Photoreceptor spectral sensitivity peaks are similar to previous measurements from Bombus terrestris, although there is a significant difference in the peak sensitivity of the blue receptor, which is shifted in the short wave direction by 12–13 nm in B. impatiens compared to B. terrestris

    FReD: the Floral Reflectance Database - a web portal for analyses of flower colour

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    Background: Flower colour is of great importance in various fields relating to floral biology and pollinator behaviour. However, subjective human judgements of flower colour may be inaccurate and are irrelevant to the ecology and vision of the flower's pollinators. For precise, detailed information about the colours of flowers, a full reflectance spectrum for the flower of interest should be used rather than relying on such human assessments. Methodology/Principal Findings: The Floral Reflectance Database (FReD) has been developed to make an extensive collection of such data available to researchers. It is freely available at http://www.reflectance.co.uk. The database allows users to download spectral reflectance data for flower species collected from all over the world. These could, for example, be used in modelling interactions between pollinator vision and plant signals, or analyses of flower colours in various habitats. The database contains functions for calculating flower colour loci according to widely-used models of bee colour space, reflectance graphs of the spectra and an option to search for flowers with similar colours in bee colour space. Conclusions/Significance: The Floral Reflectance Database is a valuable new tool for researchers interested in the colours of flowers and their association with pollinator colour vision, containing raw spectral reflectance data for a large number of flower species

    Retinoid-independent motor neurogenesis from human embryonic stem cells reveals a medial columnar ground state

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    A major challenge in neurobiology is to understand mechanisms underlying human neuronal diversification. Motor neurons (MNs) represent a diverse collection of neuronal subtypes, displaying differential vulnerability in different human neurodegenerative diseases. The ability to manipulate cell subtype diversification is critical to establish accurate, clinically relevant in vitro disease models. Retinoid signalling contributes to caudal precursor specification and subsequent MN subtype diversification. Here we investigate the necessity for retinoic acid in motor neurogenesis from human embryonic stem cells. We show that activin/nodal signalling inhibition, followed by sonic hedgehog agonist treatment, is sufficient for MN precursor specification, which occurs even in the presence of retinoid pathway antagonists. Importantly, precursors mature into HB9/ChAT-expressing functional MNs. Furthermore, retinoid-independent motor neurogenesis results in a ground state biased to caudal, medial motor columnar identities from which a greater retinoid-dependent diversity of MNs, including those of lateral motor columns, can be selectively derived in vitro

    Kin discrimination and possible cryptic species in the social amoeba Polysphondylium violaceum

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    Abstract Background The genetic diversity of many protists is unknown. The differences that result from this diversity can be important in interactions among individuals. The social amoeba Polysphondylium violaceum, which is a member of the Dictyostelia, has a social stage where individual amoebae aggregate together to form a multicellular fruiting body with dead stalk cells and live spores. Individuals can either cooperate with amoebae from the same clone, or sort to form clonal fruiting bodies. In this study we look at genetic diversity in P. violaceum and at how this diversity impacts social behavior. Results The phylogeny of the ribosomal DNA sequence (17S to 5.8S region) shows that P. violaceum is made up of at least two groups. Mating compatibility is more common between clones from the same phylogenetic group, though matings between clones from different phylogenetic groups sometimes occurred. P. violaceum clones are more likely to form clonal fruiting bodies when they are mixed with clones from a different group than when they are mixed with a clone of the same group. Conclusion Both the phylogenetic and mating analyses suggest the possibility of cryptic species in P. violaceum. The level of divergence found within P. violaceum is comparable to the divergence between sibling species in other dictyostelids. Both major groups A/B and C/D/E/F show kin discrimination, which elevates relatedness within fruiting bodies but not to the level of clonality. The diminished cooperation in mixes between groups suggests that the level of genetic variation between individuals influences the extent of their cooperation
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