Search results for "holobiont"
showing 10 items of 16 documents
Woody Plant Declines. What’s Wrong with the Microbiome?
2020
National audience; Woody plant (WP) declines have multifactorial determinants as well as a biological and economic reality. The vascular system of WPs involved in the transport of carbon, nitrogen, and water from sources to sinks has a seasonal activity, which places it at a central position for mediating plant–environment interactions from nutrient cycling to community assembly and for regulating a variety of processes. To limit effects and to fight against declines, we propose: (i) to consider the WP and its associated microbiota as an holobiont and as a set of functions; (ii) to consider simultaneously, without looking at what comes first, the physiological or pathogenic disorders; and (…
Beyond cells – The virome in the human holobiont
2019
Viromics, or viral metagenomics, is a relatively new and burgeoning field of research that studies the complete collection of viruses forming part of the microbiota in any given niche. It has strong foundations rooted in over a century of discoveries in the field of virology and recent advances in molecular biology and sequencing technologies. Historically, most studies have deconstructed the concept of viruses into a simplified perception of viral agents as mere pathogens, which demerits the scope of large-scale viromic analyses. Viruses are, in fact, much more than regular parasites. They are by far the most dynamic and abundant entity and the greatest killers on the planet, as well as th…
Caractérisation de l’holobionte vigne : des bio-indicateurs du dépérissement du sol aux feuilles
2018
Le projet HOLOVITI porte sur l’holobionte (du grec holo = tout et bios = vie), c’est-à-dire l’unité biologique composée de l’hôte (ici la vigne) et tous les microorganismes avec lesquels la plante interagit et établit un dialogue. « Nous étudions le lien physiologique entre le microbiote et le cep, depuis le sol jusqu’aux feuilles, précisent Pierre-Emmanuel Courty (INRAE Dijon Bourgogne Franche Comté) et Sophie Trouvelot (Institut Universitaire de la Vigne et du Vin -Université de Bourgogne), co- porteurs de ce projet. Le projet HOLOVITI a pour objectif majeur d’identifier des bio-indicateurs d’origine végétale et microbienne qui traduiraient l’état sanitaire et physiologique de la vigne et…
Formally described species woefully underrepresent phylogenetic diversity in the common lichen photobiont genus Trebouxia (Trebouxiophyceae, Chloroph…
2020
Lichens provide valuable systems for studying symbiotic interactions. In lichens, these interactions are frequently described in terms of availability, selectivity and specificity of the mycobionts and photobionts towards one another. The lichen-forming, green algal genus Trebouxia Puymaly is among the most widespread photobiont, associating with a broad range of lichen-forming fungi. To date, 29 species have been described, but studies consistently indicate that the vast majority of species-level lineages still lack formal description, and new, previously unrecognized lineages are frequently reported. To reappraise the diversity and the evolutionary relationships of species-level lineages …
The genetic structure of the cosmopolitan three-partner lichenRamalina farinaceaevidences the concerted diversification of symbionts
2012
The epiphytic lichen Ramalina farinacea is distributed throughout the northern hemisphere in which the same two algal Trebouxia species (provisionally named TR1 and TR9) coexist in every thallus. Ramalina farinacea symbionts were characterized based on the two fungal nuclear loci (nrITS and rpb2 ) along with the primary and secondary structures of nrITS from each Trebouxia species in the Iberian Peninsula and Canary Islands. The results indicated a noticeable genetic differentiation between mycobionts from these two geographic areas and also suggested concerted changes in the three partners of a lichen symbiosis toward two clearly distinguishable ‘holobiont’ lineages. Modeling of ITS2 RNA s…
Cnidarian Interaction with Microbial Communities: From Aid to Animal’s Health to Rejection Responses
2018
The phylum Cnidaria is an ancient branch in the tree of metazoans. Several species exert a remarkable longevity, suggesting the existence of a developed and consistent defense mechanism of the innate immunity capable to overcome the potential repeated exposure to microbial pathogenic agents. Increasing evidence indicates that the innate immune system in Cnidarians is not only involved in the disruption of harmful microorganisms, but also is crucial in structuring tissue-associated microbial communities that are essential components of the Cnidarian holobiont and useful to the animal’s health for several functions, including metabolism, immune defense, development, and behavior. Someti…
Editorial: Recent Advances in Symbiosis Research: Integrative Approaches
2016
Symbiosis research is being transformed by new model systems and technologies that bring forth unexpected discoveries. Technological advances such as those stemming from Next Generation Sequencing enable detailed insights into the molecular bases of symbiotic relationships, and have revolutionized the study of complex microbial communities. As new data gathers, the need grows for a conceptual framework that helps organize and make sense of the information. Here, we present some ground-breaking works pushing the boundaries of our understanding of symbiosis in a variety of systems, as well as some state-of-the-art attempts at putting forward organizing principles for the whole of symbiology.
The Microbiota Promotes Arterial Thrombosis in Low-Density Lipoprotein Receptor-Deficient Mice
2019
Our results demonstrate a functional role for the commensal microbiota in atherothrombosis. In a ferric chloride injury model of the carotid artery, GF C57BL/6J mice had increased occlusion times compared to colonized controls. Interestingly, in late atherosclerosis, HFD-fed GF Ldlr−/− mice had reduced plaque rupture-induced thrombus growth in the carotid artery and diminished ex vivo thrombus formation under arterial flow conditions.
Contribution to the research of microbial and RedOx bio-indicators for the early characterisation of wood diseases in grapevines
2022
Grapevine trunk diseases, linked to pathogenic fungi whose mechanism of action is still poorly characterised, are responsible for grapevine decline in vineyards throughout the world, causing significant losses in productivity and yield in the wine sector. Given the current lack of effective solutions to stop the establishment of the disease and the development of symptoms, which are irreversible but often late in relation to the pathogenic infection, early diagnosis of these diseases is essential. Considering the grapevine holobiont, i.e. the grapevine and the microbiota interacting with, we hypothesise that early bio-indicators of diseases would make it possible to identify a disturbance i…
L’holobionte vigne, un levier biologique pour lutter contre les dépérissements ?
2021
National audience; Le concept d’organisme pluricellulaire isolé montre actuellement ses limites. En effet, unorganisme interagit avec différentes communautés microbiennes (constituant son microbiote)qui modulent ses propriétés, telles que sa physiologie (ex. réponse à une attaque pathogène).L’association hôte-microorganismes définit un holobionte, dont le fonctionnement est influencépar la dynamique spatio-temporelle de leurs interactions. Ainsi, un dysfonctionnement del’holobionte vigne (par exemple lié à des pratiques culturales inadaptées ou aux changementsclimatiques) pourrait entraîner le développement de maladies ou de désordres physiologiques,sources de dépérissements, de la même man…