A5029510428- Clostridium difficile and Clostridium perfringens research
- Protein Kinase Regulation and GTPase Signaling
- Gut microbiota and health
- Cellular transport and secretion
- Cellular Mechanics and Interactions
- Microscopic Colitis
- PI3K/AKT/mTOR signaling in cancer
- Pharmaceutical and Antibiotic Environmental Impacts
- Cancer Immunotherapy and Biomarkers
- Gastrointestinal motility and disorders
- Cell death mechanisms and regulation
- Cell Adhesion Molecules Research
- Neutropenia and Cancer Infections
- Endoplasmic Reticulum Stress and Disease
- Ion channel regulation and function
- Inflammatory Biomarkers in Disease Prognosis
- Enzyme Structure and Function
- Antibiotics Pharmacokinetics and Efficacy
- Antibiotic Resistance in Bacteria
- Cancer-related Molecular Pathways
- Retinal Development and Disorders
- Coagulation, Bradykinin, Polyphosphates, and Angioedema
- Phosphodiesterase function and regulation
- Mechanisms of cancer metastasis
- Ubiquitin and proteasome pathways
Da Volterra (France)
2016-2025
Institut Curie
2000-2020
Immunology from Concept and Experiments to Translation
2020
Inserm
1999-2009
Institut National de Recherche en Santé Publique
2005
Maternité Port Royal
2002
National Institute of Allergy and Infectious Diseases
2000
National Institutes of Health
2000
University of Illinois Chicago
2000
The University of Texas Southwestern Medical Center
1994
The Drosophila (fruit fly) model system has been instrumental in our current understanding of human biology, development, and diseases. Here, we used a high-throughput yeast two-hybrid (Y2H)-based technology to screen 102 bait proteins from melanogaster , most them orthologous cancer-related and/or signaling proteins, against high-complexity fly cDNA libraries. More than 2300 protein-protein interactions (PPI) were identified, which 710 are high confidence. computation reliability score for...
Plasmalemmal caveolae are a membrane specialization that mediates transcytosis across endothelial cells and the uptake of small molecules ions by both epithelial connective tissue cells. Recent findings suggest may, in addition, be involved signal transduction. To better understand molecular composition this specialization, we have developed biochemical method for purifying from chicken smooth muscle Biochemical morphological markers indicate can obtain approximately 1.5 mg protein fraction...
Lethal toxin (LT) from Clostridium sordellii is one of the high molecular mass clostridial cytotoxins. On cultured cells, it causes a rounding cell bodies and disruption actin stress fibers. We demonstrate that LT glucosyltransferase uses UDP-Glc as cofactor to covalently modify 21-kDa proteins both in vitro vivo. glucosylates Ras, Rap, Rac. In threonine at position 35 was identified target amino acid glucosylated by LT. Other related members Ras GTPase superfamily, including RhoA, Cdc42,...
Antibiotics are life-saving drugs but severely affect the gut microbiome with short-term consequences including diarrhea and selection of antibiotic-resistant bacteria. Long-term links to allergy obesity also suggested. We devised a product, DAV132, previously showed its ability deliver powerful adsorbent, activated charcoal, in late ileum human volunteers. performed randomized controlled trial 28 volunteers treated 5-day clinical regimen fluoroquinolone antibiotic moxifloxacin 2 parallel...
Antibiotic-induced modulation of the intestinal microbiota can lead to Clostridioides difficile infection (CDI), which is associated with considerable morbidity, mortality, and healthcare-costs globally. Therefore, identification markers predictive CDI could substantially contribute guiding therapy decreasing burden. Here, we analyze hospitalized patients at increased risk in a prospective, 90-day cohort-study before after antibiotic treatment diarrhea onset. We show that developing already...
cDNA clones encoding the regulatory subunit of cAMP-dependent protein kinase (ATP:protein phosphotransferase, EC 2.7.1.37) from Dictyostelium discoideum were isolated by immunoscreening a library constructed in expression vector lambda gt11. High-affinity cAMP-binding activity was detected extracts bacteria lysogenized with these clones. Nucleotide sequence analysis three overlapping allowed determination 1195-base-pair coding for entire and containing nontranslated 5' 3' sequences. The open...
Ras oncogenes encode 21-kDa GTP-binding proteins that are capable of transforming immortalized cells in culture. bound to the inner face plasma membrane by their C-terminal extremity and thought transmit mitogenic signals via an "effector" domain spanning amino acids 32-42. Two ras-related human genes rap1A rap1B 95% homologous share with p21 same effector a similar Cys-Ali-Ali-Xaa sequence (where Ali is aliphatic acid; also known as CAAX sequence). The product gene identical Krev-1 cDNA,...
At the onset of mitosis, most adherent cells undergo cell retraction characterised by disassembly focal adhesions and actin stress fibres. Mitosis takes place in rounded cells, two daughter spread again after cytokinesis. Because well-documented ability small GTPase Rap1 to stimulate integrin-dependent adhesion spreading, we assessed its role during mitosis. We show that activity is regulated this process. Changes play an essential regulating respectively, before mitosis HeLa cells. Indeed,...
Post-translational modifications of GTPases from the Ras superfamily enable them to associate with membrane compartments where they exert their biological activities. However, no protein acting like Rho and Rab dissociation inhibitor (GDI) that regulate association has been described for closely related proteins. We report here δ subunit retinal rod phosphodiesterase (PDEδ) is able interact prenylated Rap proteins, solubilize membranes, independently nucleotide-bound (GDP or GTP) state. show...
Activation of human neutrophils involves the degranulation specific and azurophil granules. This process is GTP-dependent presence small GTP-binding proteins (SGBPs) has been detected in two granule populations. At present, none these SGBPs definitely identified. In order to characterize some obtain further insights as their potential role processes, we have used antibodies directed against ras-related rap1 rap2 proteins. By immunoblot analysis, observed that rap2p predominantly located...
Abstract During antibiotic treatments, active residuals reaching the colon profoundly affect bacterial flora resulting in emergence of resistance. To prevent these effects, we developed an enteric‐coated formulated activated‐charcoal based product, DAV132, meant to deliver its adsorbent ileum and neutralize residues proximal colon. In a randomized, control, crossover study, plasma pharmacokinetics probe drugs amoxicillin (500 mg) absorbed intestine, sulfapyridine (25 metabolized from...
Quantitative data on fecal shedding of antimicrobial-resistant bacteria are crucial to assess the risk transmission from dogs humans. Our first objective was investigate prevalence quinolone/fluoroquinolone-resistant and beta-lactam-resistant Enterobacteriaceae in France Spain. Due particular concern about possible extended-spectrum cephalosporin (ESC)-resistant isolates their owners, we characterized ESBL/pAmpC producers collected dogs. Rectal swabs 188 dogs, without signs diarrhea that had...
Abstract Background DAV132 (colon-targeted adsorbent) has prevented antibiotic-induced effects on microbiota in healthy volunteers. Objectives To assess safety and biological efficacy patients. Patients methods An open-label, randomized [stratification: fluoroquinolone (FQ) indication] multicentre trial comparing (7.5 g, 3 times a day, orally) with No-DAV132 hospitalized patients requiring 5–21 day treatment FQs at risk of Clostridioides difficile infection (CDI). FQ were started...
In an attempt to elucidate the physiological function(s) of Ras-related Rap proteins, we used yeast two-hybrid system and isolated a cDNA encoding protein that interacts with both Rap1 Rap2, but not Ras; use Rap2 mutants showed this interaction is characteristic potential effector. This was identified as RGS14, member recently discovered family RGS (‘regulators G-protein signalling’) proteins stimulate GTPase activity GTP-binding α subunit heterotrimeric G-proteins (Gα). Deletion analysis,...
Thrombopoietin (TPO) regulates growth and differentiation of megakaryocytes. We previously showed that extracellular signal-regulated kinases (ERKs) are required for TPO-mediated full megakaryocytic maturation in both normal progenitors a megakaryoblastic cell line (UT7) expressing the TPO receptor (Mpl). In these cells, intensity duration TPO-induced ERK signal controlled by several regions cytoplasmic domain Mpl. this study, we explored signaling pathways involved control. show small...
Regulator of G protein signaling (RGS) proteins are a family approximately 20 that negatively regulate through heterotrimeric protein-coupled receptors. The RGS act as GTPase-activating (GAPs) for certain Galpha subunits and effector antagonists Gqalpha. Mouse RGS14 encodes 547-amino-acid with an N-terminal domain, which is highly expressed in lymphoid tissues. In this study, we demonstrate GAP Gialpha subfamily members it attenuates interleukin-8 receptor-mediated mitogen-activated kinase...