A5033383474- Cellular transport and secretion
- Bacterial Genetics and Biotechnology
- Lipid Membrane Structure and Behavior
- Bacteriophages and microbial interactions
- Cell Adhesion Molecules Research
- Biochemical and Structural Characterization
- Receptor Mechanisms and Signaling
- Microfluidic and Bio-sensing Technologies
- Monoclonal and Polyclonal Antibodies Research
- Toxin Mechanisms and Immunotoxins
- 3D Printing in Biomedical Research
- Escherichia coli research studies
- Antibiotic Resistance in Bacteria
- Climate Change Communication and Perception
- HIV Research and Treatment
- Cell Image Analysis Techniques
- Advanced Fluorescence Microscopy Techniques
- Enzyme Production and Characterization
- Communication and COVID-19 Impact
- Erythrocyte Function and Pathophysiology
- Caveolin-1 and cellular processes
- SARS-CoV-2 and COVID-19 Research
- Protein Structure and Dynamics
- Bacterial biofilms and quorum sensing
- Galectins and Cancer Biology
Institut Pasteur
2015-2025
Université Paris Cité
1995-2025
Inserm
2016-2021
Délégation Paris 6
2018
Centre National de la Recherche Scientifique
1999-2017
Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes
2017
Springer Nature (Germany)
2014
Laboratoire de Recherche Scientifique
2013
UCLouvain
2000-2002
Centre de Génétique Moléculaire
2000
Dynamin superfamily molecular motors use guanosine triphosphate (GTP) as a source of energy for membrane-remodeling events. We found that knockdown nucleoside diphosphate kinases (NDPKs) NM23-H1/H2, which produce GTP through adenosine (ATP)-driven conversion (GDP), inhibited dynamin-mediated endocytosis. NM23-H1/H2 localized at clathrin-coated pits and interacted with the proline-rich domain dynamin. In vitro, were recruited to dynamin-induced tubules, stimulated GTP-loading on dynamin,...
Abstract Elucidating protein functions and molecular organisation requires to localise precisely single or aggregated molecules analyse their spatial distributions. We develop a statistical method SODA (Statistical Object Distance Analysis) that uses either micro- nanoscopy significantly improve on standard co-localisation techniques. Our considers cellular geometry densities of provide maps isolated associated (coupled) molecules. use with three-colour structured-illumination microscopy...
Endocytosis is critical for many cellular functions. We show that endocytosis of the common γc cytokine receptor clathrin independent by using a dominant-negative mutant Eps15 or RNA interference to knock down heavy chain. This pathway synaptojanin and requires GTPase dynamin. In addition, this process actin polymerization. To further characterize function dynamin in clathrin-independent endocytosis, particular its connection with cytoskeleton, we focused on dynamin-binding proteins interact...
One major question in molecular biology is whether the spatial distribution of observed molecules random or organized clusters. Indeed, this analysis gives information about molecules' interactions and physical interplay with their environment. The standard tool for analyzing statistically Ripley's K function, which tests randomness through computation its critical quantiles. However, quantiles' very cumbersome, hindering use. Here, we present an analytical expression these quantiles,...
ABSTRACT The live attenuated yellow fever virus (YFV) vaccine 17D stands as a “gold standard” for successful vaccine. was developed empirically by passaging the wild-type Asibi strain in mouse and chicken embryo tissues. Despite its immense success, molecular determinants virulence attenuation immunogenicity of are poorly understood. evolved several mutations genome, most which lie within envelope (E) protein. Given major role played YFV E protein during entry, it has been hypothesized that...
SARS-CoV-2 infection results in impaired interferon response patients with severe COVID-19. However, how interferes host immune responses is incompletely understood. Here, we sequence small RNAs from SARS-CoV-2-infected human cells and identify a microRNA (miRNA) derived recently evolved region of the viral genome. We show that virus-derived miRNA produces two isoforms infected by enzyme Dicer, which are loaded into Argonaute proteins. Moreover, predominant isoform targets 3'UTR...
Environmental Enteric Dysfunction (EED) refers to an incompletely defined syndrome of inflammation, reduced absorptive capacity, and barrier function in the small intestine. It is widespread among children adults low- middle-income countries also associated with poor sanitation certain gut infections possibly resulting abnormal microbiota, intestinal bacterial overgrowth (SIBO) stunting. We investigated pathogen exposure stunted non-stunted Antananarivo, Madagascar by collecting fecal...
Physical forces are essential to biological function, but their impact at the tissue level is not fully understood. The gut under continuous mechanical stress because of peristalsis. To assess influence cues on enteropathogen invasion, we combine computational imaging with a mechanically active gut-on-a-chip. After infecting device either two microbes, image behavior in real time while mapping within tissue. This achieved by reconstructing three-dimensional videos ongoing invasion and...
Skin cancer is a global health issue and mainly composed of melanoma nonmelanoma cancers. For the first clinical proof concept on humans, we decided to study good prognosis skin cancers, i.e., carcinoma basal cell. In UE, first-line treatment remains surgical resection, healing most tumors, but presents aesthetic disadvantages with high reoccurrence rate exposed areas. Moreover, therapeutic indications could extend metastasis, which different medical strategy that combine this treatment....
Growing evidence indicates that kinases are central to the regulation of endocytic pathways. Previously, we identified p21-activated kinase 1 (Pak1) as first specific regulator clathrin- and caveolae-independent endocytosis used by interleukin 2 receptor subunit (IL-2R). Here, address mechanism which Pak1 regulates IL-2Rβ endocytosis. First, show phosphorylates an activator actin polymerization, cortactin, on its serine residues 405 418. Consistently, observe a inhibition when cells...
Various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. Separate binding/translocation (B) components bind to a receptor on the cell surface, assemble enzymatic (A) component(s), mediate endocytosis toxin complex. Ultimately there is translocation A component(s) from acidified endosomes into cytosol, leading destruction actin cytoskeleton. Our results revealed that CD44, multifunctional surface mammalian cells, facilitates...
Receptor-mediated endocytosis is an essential process used by eukaryotic cells to internalise many molecules. Several clathrin-independent endocytic routes exist, but the molecular mechanism of each pathway remains be uncovered. The present study focuses on a dynamin-dependent interleukin 2 receptors (IL-2R), players immune response. Ras-related C3 botulinum toxin substrate (Rac1) and its targets, p21-activated kinases (Pak), are specific regulators this pathway, acting cortactin actin...
Summary Phosphatidylinositol 3‐kinase (PI 3‐kinase) and its target protein kinase B (Akt) are involved in various processes including internalization, chemotaxis proliferation. We analysed the activation of Akt J774 macrophages infected with virulent (pYV + ) or avirulent − Yersinia enterocolitica . During early stage infection pYV bacteria, targets, glycogen synthase 3 (GSK‐3) forkhead transcription factor (FKHRL1), became phosphorylated. This phosphorylation induction was inhibited by...
ABSTRACT Linker and deletion mutagenesis gene fusions were used to probe the possible domain structure of dodecameric outer membrane secretin PulD from pullulanase secretion pathway Klebsiella oxytoca . Insertions 24 amino acids close or within strongly predicted highly conserved amphipathic β strands in C-terminal half polypeptide (the domain) abolished sodium dodecyl sulfate (SDS)-resistant multimer formation that is characteristic this protein, whereas insertions elsewhere generally had...
Summary Pullulanase (PulA) is a 116kDa amylolytic lipoprotein secreted by the Gram‐negative bacterium Klebsiella oxytoca via general secretory pathway. A deletion strategy was used in an attempt to determine nature and location of secretion signal(s) PulA presumed be necessary for its specific secretion. The starting material gene fusion coding efficiently PulA‐β‐lactamase hybrid protein. Successive series exonuclease III‐generated deletions were remove internal segments from this hybrid....
The interleukin-2 receptor (IL-2R) is a cytokine essential for immunity that transduces proliferative signals regulated by its uptake and degradation. IL-2R well-known marker of clathrin-independent endocytosis (CIE), process devoid any coat protein, raising the question how CIE vesicle generated. Here, we investigated impact IL-2Rγ clustering in endocytosis. Combining total internal reflection fluorescence (TIRF) live imaging CRISPR-edited T cell line endogenously expressing tagged with...
The Yop virulon, which comprises a complete type III secretion system and secreted proteins, allows bacteria from the genus Yersinia to resist nonspecific immune response of host. This is encoded by plasmid called pYV in enterocolitica, enables extracellular inject six effectors (YopE, -H, -T, -O, -P, -M) into host cell. To investigate role YopP, YopM, other pYV-encoded factors on expression cell genes, we characterized transcriptome alterations infected mouse macrophages using microarray...