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The workshop provides a forum for the discussion of new research directions and applications in Artificial Life, Evolutionary Computation and in related fields, where different disciplines and research areas could effectively meet. It was first held in 2007 in Sampieri (Ragusa), as the incorporation of two separate workshops (WIVA and GSICE).

Initiated in 1969 by Pullmann and Del Re, the congress is an annual meeting to promote collaboration and friendship between Latin-speaking theoretical chemists. In its early years, European researchers were the main contributors. Subsequently, the Latin American community has made a major contribution, with the emergence of teams whose international reputation now extends far beyond our own community.We are delighted to be holding this meeting at the University of Namur, 55 years after the first CHITEL was organised in Paris, France. We are sure that this 2024 edition will once again be an opportunity to take advantage of the good humour and dynamism of Latin to encourage, develop and strengthen scientific exchanges.We look forward to welcoming you at the University of Namur,The CHITEL 2024 Local Organising Committee. Website

(Update 04/04: This article is "an April Fool") A remarkable event took place during Printemps des sciences, which ran from March 18 to 24, 2024. While a visit to the UNamur Astronomical Observatory was offered to the general public on the evening of March 23, a unique phenomenon occurred.

Characterization of trehalase from Acyrthosiphon pisum for the design of new insecticides SummaryAphids are major pests in agriculture, causing direct damage to plants and acting as vectors for phytopathogenic viruses. Conventional insecticides are widely used to control them, but their toxicity and efficacy pose problems in terms of the environment, human health and the emergence of resistance to these compounds. New alternatives are therefore needed, such as biological control using predators or parasitoids. However, these methods are not always economically viable on a large scale. As part of this thesis, another approach is being explored which involves developing new insecticides targeting the biochemical functions of aphids.The project aims to discover new inhibitors of trehalase, an enzyme essential for insect energy metabolism. Inhibition of this enzyme could disrupt vital insect functions without affecting mammals. This research involved several stages: the purification and complete characterization of trehalase from Acyrthosiphon pisum (the model for this study), the in vivo, in vitro and in silico analysis of commercial inhibitors on this enzyme, before moving on to the search for new inhibitors. Two points of integrated insect management were explored, biological and chemical control.The biological side saw the study of a strain of Streptomyces naturally producing trehalase-inhibiting metabolites, notably validamycin A, a molecule recognized in the literature as one of the best inhibitors, but not applicable as an insecticide. Other molecules appear to have interesting features, but we have not been able to isolate and characterize them.The chemical side has enabled us to create a pharmacophore hypothesis based on experimental results on molecules obtained by virtual screening. Although these molecules are not usable as insecticides as they stand, this hypothesis provides a better understanding of trehalase inhibitors in general and can be used to refine future analyses. JuryProf. Jean-Yves MATROULE (UNamur), presidentDr Catherine MICHAUX (UNamur), promoter and secretaryProf. Frédéric FRANCIS (ULiège), co-promoterProf. André MATAGNE (ULiège)Dr Rudy CAPARROS (ULiège)Dr Morgan HANS (Biocidal)

The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) has just published a study in the prestigious journal Nature, listing and assessing the different values we place on nature. Nicolas Dendoncker, professor in the Department of Geography and member of the ILEE Institute at UNamur, is one of the co-authors.

Thesis subject Use of BioID within mitochondria: examples with the study of human mitochondrial co-translational import process and with the identification of MPV17 function Summary This thesis was divided into two different parts dedicated to the study of a mitochondrial process and of a mitochondrial protein using a proximity labelling assay called BioID. The first project was dedicated to the study of a poorly characterized process, the mitochondrial co-translational import. In this process, translation is coupled to the translocation of the mitochondrial proteins, alleviating the energy cost typically associated with the post-translational import relying on chaperone systems. However, the mechanisms are still unclear with only few actors identified but none that have been described in mammals yet. We thus profiled endogenously the TOM20 proxisome using BioID. Despite the enrichment of RNA binding proteins in the TOM20 proxisome, we could not demonstrate a role for a selected candidate, LARP4, in the mitochondrial co-translational import process. Nonetheless, additional uses of this BioID cell line were highlighted such as the monitoring of protein entry inside mitochondria and a potential application in the prediction of mitochondrial protein half-life.The second project was dedicated to the study of MPV17, a protein of the inner mitochondrial membrane whose gene is associated with mitochondrial DNA depletion syndrome. However, the exact molecular function of the protein is still unclear. The approach used in this project was to identify the interacting partners of MPV17, using BioID, to get additional clues about the protein function. In this project we demonstrated an interaction of MPV17 with the MICOS complex but the KO of MPV17 didn't impact mitochondria ultrastructure. However, the depletion of MPV17 protein led to increased mitochondria-derived vesicle formation. Therefore, we investigated a potential degradation of the mtDNA as the cause of the mtDNA depletion observed in MPV17 KO cells but, despite a higher mitophagy level in KO cells, the blockade of the lysosomal activity didn't prevent the depletion. Additional in silico analyses suggested a channel activity of MPV17 further supported by its direct interaction with the Cyclophilin D, a protein of the mitochondrial permeability transition pore. Interestingly, MPV17 KO cells also display higher level of mitochondrial calcium which would be related to the degradation of the mtDNA since the blockade of mitochondrial calcium entry prevents the depletion. We thus propose a role of MPV17 as a potential new member of the mitochondrial permeability transition pore whereas in the absence of the protein, the build-up of calcium inside the mitochondria would lead to the observed mtDNA degradation. Jury Prof. Benoît MUYLKENS (UNamur), ChairmanProf. Patsy RENARD (UNamur), Promoter and SecretaryProf. Thierry ARNOULD (UNamur), Co-PromoterProf. Dr. David PLA-MARTIN (Heinrich Heine University Düsseldorf, Germany)Dr. Timothy WAI (Institut Pasteur Paris, France)Prof. David PLA-MARTIN (Heinrich Heine University Düsseldorf, Germany)Dr. Timothy WAI (Institut Pasteur de Paris, France)Prof. Guy LENAERS (Université d'Angers, France)Prof. Sven EYCKERMAN (Universiteit Gent)

Maxime André, a promising doctoral student at the University of Namur's Faculty of Computer Science, has been named the winner of the prestigious SofinaBoël Fund for Education and Talent 2024 scholarship. This recognition will enable him to pursue his innovative research on the international stage.

Chairman of the Board of Directors of the Agence du Numérique (ADN), entrepreneur and co-founder of several start-ups, entrepreneurial coach, university lecturer notably in the BAGI master's program at UNamur, columnist: Roald Sieberath is a man who runs out of time to invest in projects he knows will bring results. He's a bearer of meaning, creativity, innovation and solutions. By placing people and multidisciplinarity at the heart of digital development and entrepreneurship, he is confident about the future of our society and the deployment of Wallonia..

In 2023, UNamur opened a fourth CaNDLE call funded through the joint support of the Fonds Jérôme pour le développement durable and the Assemblée des Cercles of UNamur students. Discover one of the 7 selected projects.

In 2023, UNamur opened a fourth CaNDLE call funded through the joint support of the Fonds Jérôme pour le développement durable and the Assemblée des Cercles of UNamur students. Discover one of the 7 selected projects.

Summary: Impact of the UPR pathway on the establishment of the UVB-induced senescent phenotype Skin aging, influenced by a combination of intrinsic and extrinsic factors, leads to damage capable of altering skin functions. Among extrinsic factors, ultraviolet (UV) radiation is responsible for skin photoaging. In particular, these elements lead to an accumulation of senescent cells capable of contributing to the development of age-related pathologies such as skin cancers. Indeed, senescence is accompanied by profound morphological and molecular changes within the cell. This includes a modification of its secretome, which becomes enriched with pro-inflammatory cytokines, growth factors and extracellular matrix remodeling enzymes, altering the characteristics of tissues as they age. Nevertheless, the precise mechanisms leading to the senescent phenotype induced by UVB remain largely unknown. In this context, the main objective of this work was to identify molecular mechanisms underlying the establishment of UVB-induced senescence in normal human dermal fibroblasts (NHDFs), mechanisms that could contribute to skin aging. In vitro, we confirmed that repeated UVB exposures induce premature senescence in NHDFs and that this state is associated with activation of the three branches of the UPR (Unfolded Protein Response) pathway responsible for maintaining homeostasis of the endoplasmic reticulum (ER), the primary secretory compartment. These observations were supported by transcriptomic analysis, revealing regulatory elements linked to major senescence pathways and ER functions in UVB-exposed NHDFs. Subsequently, we showed that the ATF6α branch plays a central role in the occurrence of biomarkers of the UVB-induced senescent phenotype. Indeed, ATF6α invalidation not only protects against UVB-induced morphological changes, but reduces the percentage of SA-βgalactosidase (SA-βgal)-positive cells, prevents persistent DNA damage, and alters the expression of major factors of the senescence-associated secretory phenotype (SASP). As SASP exerts, among other things, a pro-tumoral action, we sought to assess whether the conditioned medium (CM) of UVB-exposed fibroblasts invalidated for ATF6α could impact the migration and invasion potential of melanoma-derived cells. However, we did not observe any ATF6α-dependent pro-migratory or pro-invasive effects.To highlight a potential role for ATF6α in another biological process, we exploited our transcriptomic and secretomic analyses and identified a possible effect of ATF6α on the paracrine control of the skin environment. To explore this, we focused on SASP factors (cytokines and metalloproteases) regulated by ATF6α and whose impact on the tissue environment was known. Next, we treated a reconstructed human epidermis (RHE) model with MC derived from NHDFs exposed to UVB or not, and invalidated or not for ATF6α. Surprisingly, we observed that MC from UVB-exposed NHDFs increased RHE thickness and basal keratinocyte proliferation, via an ATF6α-dependent mechanism. Finally, we identified IL8 as a major paracrine factor involved in this process, since IL-8 blockade by neutralizing antibodies prevents excessive keratinocyte proliferation. In conclusion, we report the role of ATF6α in UVB-induced senescence as well as its impact on the preservation of skin homeostasis under stress conditions notably through the regulation of the expression of SASP components. This suggests that ATF6α and its effectors could be promising targets controlling the effects of skin aging.Abstract: Impact of the UPR pathway on the establishment of the senescent phenotype induced by UVBSkin aging, influenced by a combination of intrinsic and extrinsic factors, can result in damage that has the potential to alter skin functions. Among extrinsic factors, ultraviolet (UV) radiation is responsible for skin photoaging. These factors notably contribute to the accumulation of senescent cells which in turn can contribute to the development of age-related pathologies, including skin cancers. Indeed, senescence is characterized by profound morphological and molecular changes within the cell. This includes a modification of its secretome, which becomes enriched in pro-inflammatory cytokines, growth factors, and matrix-remodeling enzymes, altering tissue characteristics during aging. However, the exact mechanisms driving the senescent phenotype induced by UVB remain largely unknown. In this context, the main objective of this work was to identify the underlying molecular mechanisms responsible for the establishment of UVB-induced senescence in normal human dermal fibroblasts (NHDFs), mechanisms that may play a role in skin aging. In vitro, we confirmed that repeated exposures to UVB induce premature senescence of NHDFs and that this state is associated with the activation of the three branches of the Unfolded Protein Response (UPR), which are responsible for maintaining endoplasmic reticulum (ER) homeostasis, the primary cellular secretion compartment. These observations were supported by transcriptomic analysis, revealing regulatory elements related to major senescence pathways and ER functions in UVB-exposed NHDFs. Subsequently, we demonstrated that the ATF6α branch plays a central role in the development of the UVB-induced senescent phenotype. Indeed, the silencing of ATF6α not only protects against morphological changes induced by UVB, but also reduces the percentage of senescence-associated β-galactosidase (SA-βgal) positive cells, prevents the persistence of DNA damage, and alters the expression of major factors associated with the senescence-associated secretory phenotype (SASP).The SASP, exerting a pro-tumoral action, led us to assess whether the conditioned medium (CM) from UVB-exposed fibroblasts invalidated for ATF6α could impact the migration and invasion potential of melanoma cells. However, we did not observe any ATF6α-dependent pro-migratory or pro-invasive effects. To highlight a potential role of ATF6α in another biological process, we further analyzed our transcriptomic and secretomic analyses and identified a possible effect of ATF6α on the paracrine control of the skin environment. To explore this, we focused on SASP factors (cytokines and metalloproteinases) regulated by ATF6α and whose impact on tissue environment was known. Subsequently, we treated a reconstructed human epidermis (RHE) model with CM from NHDFs exposed or not to UVB and invalidated or not for ATF6α. Surprisingly, we observed that the CM from UVB-exposed NHDFs increased the thickness of the RHE as well as the proliferation of basal keratinocytes, via an ATF6α-dependent mechanism. Finally, we identified IL8 as a major paracrine factor involved in this process, as blocking IL-8 with neutralizing antibodies prevented excessive proliferation of keratinocytes. In conclusion, we report the role of ATF6α in UVB-induced senescence and its impact on the preservation of skin homeostasis under stress conditions, particularly through the regulation of the expression of SASP components. This suggests that ATF6α and its effectors could be promising targets for controlling the effects of skin aging. Jury Prof. Yves POUMAY (Department of Medicine, UNamur), chairmanProf. Florence CHAINIAUX (Department of Biology, UNamur), promoter and secretaryProf. Olivier PLUQUET (Canther, University of Lille), co-promoterProf. Isabelle PETROPULOS (Adaptation Biologique et Vieillissement, Sorbonne Université)Prof. Jérôme LAMARTINE (Laboratoire de Biologie Tissulaire et d'Ingénierie thérapeutique, Université Claude Bernard Lyon 1)Prof. Fabienne FOUFELLE (Maladies métaboliques, diabète et comorbidités, Sorbonne Université)

EMBO Courses and Workshops are selected for their excellent scientific quality and timelines, provision of good networking activities for all participants and speaker gender diversity (at least 40% of speakers must be from the underrepresented gender). Organisers are encouraged to implement measures to make the meeting environmentally more sustainable.Upon registration - More info and registration on the EMBO website.