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On the occasion of the International Day of Women and Girls in Science proclaimed on February 11 by the United Nations General Assembly, and as part of the European alliance European Space University for Earth and Humanity (UNIVERSEH) focusing on the theme of space, discover the testimonies of four women scientists from UNamur working on astronomical themes.

In an ever-changing world, where health, environmental and societal crises are intertwined, it is becoming imperative to rethink health in a global and interconnected approach. It was against this backdrop that the Faculty of Medicine at the University of Namur inaugurated its new "One Health" teaching unit (UE) on Thursday February 06, 2025, in the presence of Minister Yves Coppieters. This initiative, offered to all UNamur undergraduates, aims to train tomorrow's healthcare professionals in a systemic vision, where human, animal and environmental health are considered as one and the same reality.

Jury Prof. Benoît MUYLKENS (URVI, Université de Namur), PresidentProf. Carine MICHIELS (URBC, Université de Namur), SecretaryProf. Xavier DE BOLLE (URBC, Université de Namur)Prof. René REZSOHAZY (LIBST, Université catholique de Louvain)Prof. Florian STEINER (Dept. of Molecular and Cellular Biology, Université de Genève)Prof. Germano CECERE (Department of developmental and Stem Cell Biology, Institut Pasteur) Summary In animals, germ cells are often distinguished from somatic lineages at the earliest stages of embryogenesis. In some organisms, germ blastomeres appear to enter a state of transcriptional quiescence. For example, in the worm Caenorhabditis elegans, transcription is activated in somatic blastomeres as early as the 4-cell stage, whereas it is not initiated in germline blastomeres until the 100-cell stage. This transcriptional repression in germ blastomeres has been attributed to the PIE-1 protein, specifically localized in these cells from the first embryonic division. PIE-1 is thought to inhibit the activity of CDK-9, a cyclin-dependent kinase previously considered essential for the phosphorylation of serine 2 (CTD-Ser2) of the C-terminal domain (CTD) of RNA polymerase II and for transcription elongation. However, recent studies, showing that embryogenesis proceeds normally in a mutant strain expressing a CTD in which serines 2 is replaced by an alanine (CTD-S2A) and identifying CDK-12 as the main kinase phosphorylating CTD-Ser2, call this model into question.To study the transcriptome of germline blastomeres in the worm C. elegans, an approach combining cell sorting and RNA sequencing (RNA-seq) was developed. Pilot analyses validated this method on a wild-type strain, enabling its use on a strain in which PIE-1 can be specifically degraded using the Auxin-Inducible Degron (AID) system. This made it possible to examine the effect of PIE-1 depletion on the transcriptome of germline blastomeres revealing that in its absence, germline blastomeres adopt a transcriptional profile close to that of somatic blastomeres, confirming the fundamental role of PIE-1 in preserving germline identity during embryogenesis. In parallel, the fission yeast Schizosaccharomyces pombe was used to analyze the consequences of PIE-1 expression in a heterologous organism. The results showed that PIE-1 by localizing near transcription termination sites induces further transcription by RNA polymerase II beyond the termination site, leading to transcription of intergenic regions. These observations led to the hypothesis that in C. elegans,within germinal blastomeres, PIE-1 might regulate alternative polyadenylation in 3' untranslated regions, producing longer RNA isoforms susceptible to degradation. In the absence of PIE-1, shorter isoforms could be generated, allowing accumulation of somatic transcripts and potentially degradation of maternal mRNAs via somatic protein translation. Although further investigations are required in C. elegans to validate this hypothesis, it provides an innovative conceptual framework for understanding the role of PIE-1, independent of CTD-Ser2 phosphorylation.

Jury Prof. Marielle BOONEN (UNamur), presidentProf. Henri-François RENARD (UNamur), secretaryProf. Claire HIVROZ (PSL University)Prof. Michel GHISLAIN (UCLouvain)Prof. Pierre VAN DER BRUGGEN (UCLouvain)Prof. Ludger JOHANNES (PSL University)Prof. Pierre MORSOMME (UCLouvain) Summary Clathrin-independent endocytosis (CIE) mediates the cellular uptake of endogenous and exogenous cargoes, including bacterial toxins and viruses. Endophilin A3-mediated endocytosis is a specific CIE mechanism that differs from fast endophilin-mediated endocytosis (FEME), with ALCAM and L1CAM being the first confirmed Endophilin A3-specific cargoes. Here, we report ICAM1 as a new Endophilin A3-dependent endocytic cargo. ALCAM and ICAM1 are important components of immune synapses (IS), which are polarized structures formed between immune cells and target cells, such as cancer cells. These molecules transduce essential co-stimulatory signals to T cells to help their effective activation and proliferation. We find that both ALCAM and ICAM1 serve as cargoes for retromer-dependent retrograde transport to the trans-Golgi network (TGN) in cancer cells. Interestingly, disrupting Endophilin A3-mediated endocytosis or retromer-dependent retrograde transport machinery impairs activation of autologous cytotoxic CD8 T cells, possibly by affecting the polarized redistribution of immune synapse components at the plasma membrane. Altogether, our findings demonstrate that CIE and retrograde transport are key pathways in cancer cells that promote the activation of cytotoxic CD8 T cells.

Jury Prof. Yves CAUDANO (UNamur), chairmanProf. André FÜZFA (UNamur), secretaryProf. Dominique LAMBERT (UNamur)Dr. Jérémy REKIER (Observatoire royal de Belgique et UCLouvain)Prof. Dr. Félix FINSTER (Regensburg University) Summary Sounding the Universe with a relativistic solar sailboat or Einstein-Dirac fermionsThe Universe exerts a curiosity on man that is both undeniable and fundamental. To unravel the mysteries of the Cosmos, man is driven to develop two major investigative strategies: direct exploration by sending space probes, and indirect exploration by observing cosmic electromagnetic fields, gravitational waves or particles such as fermions.Following these two strategies, in this thesis we develop, in the first approach (consisting of sending a space probe), a relativistic kinematic and dynamical model of photonic sails (light sails) with arbitrary reflectivity and absorbance, moving in a non-rectilinear manner with the aim of exploring interstellar space. The problem is to determine the sail's trajectory in a Minkowski spacetime, a four-dimensional variety. From detailed calculations, we obtain the sail's universe line in the laser reference frame as a function of the sail's proper time.The second approach applies the Two-State Vector Formalism and weak measurements to a homogeneous, isotropic cosmological framework. By coupling Dirac spinners to classical gravity, we calculate weak values of the energy-impulse tensor, the Z component of spin and pure states. Extending the work of Finster and Hainzl on Einstein-Dirac cosmology, we show that the accelerated expansion of the Universe can be interpreted as a consequence of post-selection. We also demonstrate that weak measurements can amplify signals using simpler equipment, thanks to judicious selection of the initial and final state vectors. In addition, this procedure highlights certain geometric properties of the Cosmos' three-dimensional space, offering a new way of exploring the structure of the Universe.We also examine the mathematical structure on which the Dirac equation rests beyond the usual dimension and signature. This reveals a rich internal symmetry and gives rise to a particularly aesthetic diagrammatic representation. Abstract Probing the Universe with a Relativistic Light Sail or Einstein-Dirac FermionsHumanity's profound curiosity about the cosmos is both undeniable and fundamental. To demystify the Universe, humankind is compelled to develop both direct and indirect probing strategies: direct exploration through physical visits using probes, and indirect exploration by observing cosmic electromagnetic field, gravitational waves and particles such as fermions.Building on these two strategies, this thesis proposes two distinct approaches to probing the Universe. In the first approach, we present a relativistic kinematic and dynamic model of light sails with arbitrary reflectivity and absorptance, undergoing non-rectilinear motion as a method of interstellar exploration. The problem involves solving for the trajectory of the sail in a 4-dimensional Minkowski spacetime manifold. By detailed computation, we derive the worldline of the sail in the laser's frame in the sail's proper time.The second approach applies the Two-State Vector Formalism and weak measurements to a spatially homogeneous and isotropic cosmological framework. Coupling Dirac spinors with classical gravity, we compute weak values of the energy-momentum tensor, the Z-component of spin, and pure states. Extending the work of Finster and Hainzl on Einstein-Dirac cosmology, we demonstrate that the Universe's accelerated expansion can be interpreted as a consequence of post-selection. We also show that weak measurements can amplify signals with simpler equipment by carefully selecting initial and final state vectors. This process also reveals geometric properties of the spacelike three-manifold of the Cosmos, opening new way on probing the structure of the Universe.We explore also the mathematical framework underlying the Dirac equation beyond the standard dimension and signature. This enterprise reveals its symmetrically rich properties and aesthetic diagrammatic representation.

Helping us to age independently and in good health. This is the aim of Charlotte Beaudart's research into sarcopenia, an age-related disease that can occur as early as the age of 50. The work of the UNamur researcher and member of the Narilis Institute has been rewarded once again, as she has just been awarded the title of "Namuroise of the Year", for the Sciences category!

Since the discovery of fire in prehistoric times, humans have been fascinated by matter, its properties, and the changes that occur naturally or as a result of human intervention. Now known as "chemists," specialists in the reactivity of matter continue to pursue the art of experimentation and discovery. The products of their essential knowledge are applied in the fields of nutrition, health, hygiene, transportation, sports, construction, and environmental protection. 

Health is your most valuable asset. To cope with pain and illness, you regularly use medications. Natural, synthetic, biosynthetic... the choice is vast. Pharmacists, who are medication specialists, are there to advise you. You are familiar with the dispensing pharmacist, but pharmacy graduates can perform many other activities to help improve our health and quality of life. 

Professor Eli Thoré and Justine Bélik have just been honoured by the Adrien Bauchau Fund (FAB). Created in memory of the founder of the Biology Department at UNamur, the FAB has been promoting excellence in education and research in the life sciences since 1989.

An unusual piece of research recently mobilized teams from UNamur's Biology Department. Genetic analyses carried out by the Environmental and Evolutionary Biology Research Unit (URBE) were able to confirm the protected status of a herd of wild mouflons based in Gesves, and thus highlight the importance of saving them.