French National Institute for Agricultural Research (INRA) View Institution's Website 4 articles published in JoVE Biochemistry A Fluorogenic Peptide Cleavage Assay to Screen for Proteolytic Activity: Applications for coronavirus spike protein activation Javier A. Jaimes*1,2, Jean K. Millet*1,3, Monty E. Goldstein1,4, Gary R. Whittaker1, Marco R. Straus1 1Department of Microbiology and Immunology, College of Veterinary Medicine, Cornell University, 2Department of Microbiology, College of Agricultural and Life Sciences, Cornell University, 3Virologie et Immunologie Moléculaires, Domaine de Vilvert, INRA, 4Department of Cell Biology and Molecular Genetics, University of Maryland We present a fluorogenic peptide cleavage assay that allows a rapid screening of the proteolytic activity of proteases on peptides representing the cleavage site of viral fusion peptides. This method can also be used on any other amino acid motif within a protein sequence to test for the protease activity. Developmental Biology Analysis of Chromosome Segregation, Histone Acetylation, and Spindle Morphology in Horse Oocytes Federica Franciosi1, Irene Tessaro1,2, Rozenn Dalbies-Tran3, Cecile Douet3, Fabrice Reigner4, Stefan Deleuze5, Pascal Papillier3, Ileana Miclea6, Valentina Lodde1, Alberto M. Luciano1, Ghylene Goudet3 1Department of Health, Animal Science and Food Safety, University of Milan, 2IRCCS. Istituto Ortopedico Galeazzi, 3PRC, CNRS, IFCE, Université de Tours, INRA, 4PAO, INRA, 5Clinique des Animaux de Compagnie et des Équidés, Université de Liège, 6University of Agricultural Sciences and Veterinary Medicine, Cluj-Napoca, Romania This manuscript describes an experimental approach to morphologically and biochemically characterize horse oocytes. Specifically, the present work illustrates how to collect immature and mature horse oocytes by ultrasound-guided ovum pick-up (OPU) and how to investigate chromosome segregation, spindle morphology, global histone acetylation, and mRNA expression. Medicine Increasing Pulmonary Artery Pulsatile Flow Improves Hypoxic Pulmonary Hypertension in Piglets Audrey Courboulin1, Chantal Kang2, Olivier Baillard3,4,5, Sebastien Bonnet1, Pierre Bonnet6 1Department of Medicine, Pulmonary Hypertension Research Group (CRIUCPQ), Laval University, 2Institut National de la Recherche Agronomique, 3Université Diderot Paris, Sorbonne Paris Cité, 4Hôpital Lariboisière, Physiologie clinique Explorations Fonctionnelles, 5INSERM U 965, 6Service de Cardiologie, Centre Hospitalier Universitaire Tours Pulmonary hypertension is associated with a significant reduction in pulmonary artery pulsatility, contractility and elasticity, contributing to an increase in pulmonary artery pressure and pulmonary resistance. Using a hypoxic piglet model, this study demonstrated that improving pulmonary artery plasticity using a newly developed pulsatile catheter improves hypoxic pulmonary hypertension. Immunology and Infection The Insect Galleria mellonella as a Powerful Infection Model to Investigate Bacterial Pathogenesis Nalini Ramarao1, Christina Nielsen-Leroux1, Didier Lereclus1 1INRA, Micalis UMR1319, France Oral and intra haemocolic infection of larvae of the greater wax moth Galleria mellonella is described. This insect can be used to study virulence factors of entomopathogenic as well as mammalian opportunistic bacteria. Rearing of the insects, methods of infection and examples of in vivo analysis are described.