Search results for "Vertebrates"
showing 10 items of 440 documents
Chironomus riparius exposure to fullerene-contaminated sediment results in oxidative stress and may impact life cycle parameters
2015
A key component of understanding the potential environmental risks of fullerenes (C60) is their potential effects on benthic invertebrates. Using the sediment dwelling invertebrate Chironomus riparius we explored the effects of acute (12 h and 24 h) and chronic (10 d, 15 d, and 28 d) exposures of sediment associated fullerenes. The aims of this study were to assess the impact of exposure to C60 in the sediment top layer ((0.025, 0.18 and 0.48) C60 mg/cm2) on larval growth, oxidative stress and emergence rates and to quantify larval body burdens in similarly exposed organisms. Oxidative stress localization was observed in the tissues next to the microvilli and exoskeleton through a method fo…
A Wickerhamomyces anomalus Killer Strain in the Malaria Vector Anopheles stephensi
2013
The yeast Wickerhamomyces anomalus has been investigated for several years for its wide biotechnological potential, especially for applications in the food industry. Specifically, the antimicrobial activity of this yeast, associated with the production of Killer Toxins (KTs), has attracted a great deal of attention. The strains of W. anomalus able to produce KTs, called "killer" yeasts, have been shown to be highly competitive in the environment. Different W. anomalus strains have been isolated from diverse habitats and recently even from insects. In the malaria mosquito vector Anopheles stephensi these yeasts have been detected in the midgut and gonads. Here we show that the strain of W. a…
Automatic image-based identification and biomass estimation of invertebrates
2020
1. Understanding how biological communities respond to environmental changes is a key challenge in ecology and ecosystem management. The apparent decline of insect populations necessitates more biomonitoring but the time-consuming sorting and expert-based identification of taxa pose strong limitations on how many insect samples can be processed. In turn, this affects the scale of efforts to map and monitor invertebrate diversity altogether. Given recent advances in computer vision, we propose to enhance the standard human expert-based identification approach involving manual sorting and identification with an automatic image-based technology. 2. We describe a robot-enabled image-based ident…
Land invertebrates of Columbretes Islands : new species
2020
Este artículo se encuentra disponible en la siguiente URL: https://www.mdpi.com/2071-1050/13/4/1776 La fauna terrestre de invertebrados del archipiélago protegido de Columbretes es poco conocida. Además, los pocos estudios existentes se centran en su isla principal, Illa Grossa. Aquí presentamos el listado de espe-cies de invertebrados no registradas, hasta el momento, en el archipiélago, resultados obtenidos mediante una combinación de capturas con trampas de caída, avistamientos y recolecciones aleatorias realizadas tanto en Illa Grossa como en otros tres islotes de este archipiélago. Mediante el primer método se recolectaron un total de 14.830 especímenes entre 2008-2011. La mayor cantid…
Structural and functional diversity of the lectin repertoire in teleost fish: Relevance to innate and adaptive immunity
2011
Protein–carbohydrate interactions mediated by lectins have been recognized as key components of innate immunity in vertebrates and invertebrates, not only for recognition of potential pathogens, but also for participating in downstream effector functions, such as their agglutination, immobilization, and complement-mediated opsonization and killing. More recently, lectins have been identified as critical regulators of mammalian adaptive immune responses. Fish are endowed with virtually all components of the mammalian adaptive immunity, and are equipped with a complex lectin repertoire. In this review, we discuss evidence suggesting that: (a) lectin repertoires in teleost fish are highly dive…
Whole-lake experiments reveal the fate of terrestrial particulate organic carbon in benthic food webs of shallow lakes
2014
Lake ecosystems are strongly linked to their terrestrial surroundings by material and energy fluxes across ecosystem boundaries. However, the contribution of terrestrial particulate organic carbon (tPOC) from annual leaf fall to lake food webs has not yet been adequately traced and quantified. In this study, we conducted whole-lake experiments to trace artificially added tPOC through the food webs of two shallow lakes of similar eutrophic status, but featuring alternative stable regimes (macrophyte rich vs. phytoplankton dominated). Lakes were divided with a curtain, and maize (Zea mays) leaves were added, as an isotopically distinct tPOC source, into one half of each lake. To estimate the …
Polymorphism in Developmental Mode and Its Effect on Population Genetic Structure of a Spionid Polychaete, Pygospio elegans
2012
Population genetic structure of sedentary marine species is expected to be shaped mainly by the dispersal ability of their larvae. Long-lived planktonic larvae can connect populations through migration and gene flow, whereas species with nondispersive benthic or direct-developing larvae are expected to have genetically differentiated populations. Poecilogonous species producing different larval types are ideal when studying the effect of developmental mode on population genetic structure and connectivity. In the spionid polychaete Pygospio elegans, different larval types have been observed between, and sometimes also within, populations. We used microsatellite markers to study population st…
Centrins, gatekeepers for the light-dependent translocation of transducin through the photoreceptor cell connecting cilium
2006
Centrins are members of a highly conserved subgroup of the EF-hand superfamily of Ca(2+)-binding proteins commonly associated with centrosome-related structures. In the retina, centrins are also prominent components of the photoreceptor cell ciliary apparatus. Centrin isoforms are differentially localized at the basal body and in the lumen of the connecting cilium. All molecular exchanges between the inner and outer segments occur through this narrow connecting cilium. Ca(2+)-activated centrin isoforms bind to the visual heterotrimeric G-protein transducin via an interaction with the betagamma-subunit. Ca(2+)-dependent assemblies of centrin/G-protein complexes may regulate the transducin mo…
Grouping behaviour impacts on the parasitic pressure and squamation of sharks
2022
The evolution of grouping behaviour involves a complex trade-off of benefits and costs. Among the latter, an increase in the risk of parasitic transmission is a well-documented phenomenon that has likely promoted the evolution of defensive mechanisms in aquatic vertebrates. Here, we explore the relationship between grouping behaviour, parasitic richness (∼parasitic pressure), and the evolution of potential defensive traits in the squamation of sharks through phylogenetic, standard and zero-inflation regression models. Our results demonstrate that sharks that frequently aggregate show increased parasitic pressure, which may constitute an agent of selection. Accordingly, their squamation is c…
Sex chromosomes in vertebrates: XX/XY against ZZ/ZW.
2011
It was noted only recently that the mammalian X/Y sex chromosome system originated late in our therian ancestors. The question is, what makes the X/Y sex chromosome system so special that it has replaced the original Z/W sex chromosome system? Two classes of genes are overrepresented on the X chromosome: sex and reproduction genes and brain-related genes. The X chromosome has acquired bursts of young male-biased genes engaged in sex and reproduction which exemplifies the dynamics of sex chromosome evolution. Brain genes are old genes and display the most conserved transcriptome. The new therian X chromosome was formed by fusion of chromosome building blocks already bearing the highest densi…