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Pirenne, L.

Publications and source records attributed to Pirenne, L..

3 recordsLinked to original sources

Trigeminal ganglion and tooth innervation modifications following genetic and pharmacological Nogo-A inhibition

Nogo-A is a major regulator of neural development and regeneration, but its role in tooth innervation remains largely unknown. Neurons from trigeminal ganglia support teeth homeostasis and regeneration, and disorders of their function could have significant pathophysiological consequences. In this study, we show that Nogo-A is expressed in the trigeminal ganglia and in the neurons innervating the teeth, and that its deletion affects both the number and patterning of neurons in teeth. In organotypic cultures, Nogo-A blocking antibodies affect the trigeminal ganglia-derived neuronal outgrowths and allow premature innervation of tooth germs. RNA sequencing analysis revealed that Nogo-A deletion induces alterations linked to functions at synapses and interference with neurotrophin signalling during the differentiation and maturation of trigeminal neurons. Taken together, these results reveal for the first time the importance of Nogo-A as a major regulator of tooth innervation and point to its potential as a clinical therapeutic target.

neuroscience↗

The Orsay Virus as a model for population-wide viral infection dynamics

To this day, epidemics pose a considerable threat to mankind. Experimental models that simulate the spread of infectious diseases are thus crucial to the inception of effective control policies. Current models have had great success incorporating virulence and host immune response but do rarely take host genetics, behavior and host environment into account. Here, we present a full-scale imaging setup that utilizes the infection of the nematode C. elegans with a positive-stranded RNA virus (Orsay Virus) to probe key epidemiological parameters and simulate the spread of infection in a whole population. We demonstrate that our system is able to quantify infection levels and host behavior at a high sampling rate and show that different host genetic backgrounds can influence viral spread, while also highlighting the influence of infection on various host behaviors. Future work will allow the isolation of key behavioral and environmental factors that affect viral spread, potentially enabling novel policies to combat the spread of viral infections. Significance StatementIn the ongoing COVID-19 pandemic, we struggle to find effective control policies that "stop the spread". While current animal models of virus spread in populations are highly sophisticated, they rarely explore effects of host behavior and its environment. We developed an experimental animal model system that allows us to visualize virus transmission in whole populations of C. elegans while also measuring behaviors. We were able to demonstrate how C. elegans genetics influences the progression of viral infection in a population and how animals adjust their behavior when infected. In the future, we envision that animal model systems like ours are used to test the effects of viral control policies on viral spread before they are applied in real world scenarios.

immunology↗

Mutations in nucleoporin NUP88 cause lethal fetal akinesia deformation sequence

Nucleoporins build the nuclear pore complex (NPC), which, as sole gate for nuclear-cytoplasmic exchange, are of outmost importance for normal cell function. Defects in the process of nucleocytoplasmic transport or in its machinery have been frequently described in human diseases, such as cancer and neurodegenerative disorders, but only in a few cases of developmental disorders. Here we report biallelic mutations in the nucleoporin NUP88 as a novel cause of lethal fetal akinesia deformation sequence (FADS) in two families. FADS comprises a spectrum of clinically and genetically heterogeneous disorders with congenital malformations related to impaired fetal movement. We show that genetic disruption of nup88 in zebrafish results in pleiotropic developmental defects reminiscent of those seen in affected human fetuses, including locomotor defects as well as defects at neuromuscular junctions. Phenotypic alterations become visible at distinct developmental stages, both in affected human fetuses and in zebrafish, whereas early stages of development are apparently normal. The zebrafish phenotypes caused by nup88 deficiency are only rescued by expressing wild-type nup88 and not the disease-linked mutant forms of nup88. Furthermore, using human and mouse cell lines as well as immunohistochemistry on fetal muscle tissue, we demonstrate that NUP88 depletion affects rapsyn, a key regulator of the muscle nicotinic acetylcholine receptor at the neuromuscular junction. Together, our studies provide the first characterization of NUP88 in vertebrate development, expand our understanding of the molecular events causing FADS, and suggest that variants in NUP88 should be investigated in cases of FADS.

cell biology↗