A5032487819- Cellular Mechanics and Interactions
- Lipid Membrane Structure and Behavior
- Cellular transport and secretion
- Caveolin-1 and cellular processes
- Force Microscopy Techniques and Applications
- Microtubule and mitosis dynamics
- Fungal and yeast genetics research
- Cell Adhesion Molecules Research
- RNA Research and Splicing
- Erythrocyte Function and Pathophysiology
- Nanopore and Nanochannel Transport Studies
- HIV Research and Treatment
- Advanced Fluorescence Microscopy Techniques
- Pain Management and Opioid Use
- Nanoparticle-Based Drug Delivery
- Complement system in diseases
- Pediatric Pain Management Techniques
- Neurofibromatosis and Schwannoma Cases
- Toxin Mechanisms and Immunotoxins
- Bacterial Infections and Vaccines
- Plant and fungal interactions
- Lipid metabolism and biosynthesis
- Bacteriophages and microbial interactions
- Nuclear Structure and Function
- Developmental Biology and Gene Regulation
Université Paris Sciences et Lettres
2016-2025
Sorbonne Université
2016-2025
Centre National de la Recherche Scientifique
2016-2025
Institut Curie
2016-2025
Physique des Cellules et Cancers
2018-2024
Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes
2024
Institute for Atomic and Molecular Physics
2011-2021
Linkou Chang Gung Memorial Hospital
2019
Chang Gung University
2019
Université Paris Cité
2018
Biosensors based on plasmonic nanostructures are widely used in various applications and benefit from numerous operational advantages. One type of application where nanostructured sensors provide unique value comparison with, for instance, conventional surface plasmon resonance, is investigations the influence nanoscale geometry biomolecular binding events. In this study, we show that "nanowells" conformally coated with a continuous lipid bilayer can be to detect preferential insulin...
Abstract Cardiolipin is a cone-shaped lipid predominantly localized in curved membrane sites of bacteria and the mitochondrial cristae. This specific localization has been argued to be geometry-driven, since CL’s conical shape relaxes curvature frustration. Although previous evidence suggests coupling between CL concentration vivo, no precise experimental data are available for curvature-based sorting vitro. Here, we test this hypothesis experiments that isolate effects lipid-bilayer...
We demonstrate that cytoskeletal actin-myosin networks can be encapsulated with high efficiency in giant liposomes by hydration of lipids an agarose hydrogel. The have cell-sized diameters 10-20 μm and a uniform actin content. show measurements membrane fluorescence intensity bending rigidity the majority are unilamellar. further network specifically anchored to biotin-streptavidin linkages. These protein-filled useful model systems for quantitative studies physical mechanisms which...
Significance Animal cells continuously move, divide, and transmit forces by actively reorganizing their internal scaffold or cytoskeleton. Molecular motors pull actin filaments together generate contraction of the cytoskeleton underneath cell membrane. We address detailed mechanism using a minimal in vitro assay: liposome membrane to which we attach molecular controlled manner. reproduce like cells. show that needs be tightly attached for efficient contraction, but, under some conditions,...
Abstract Septins are cytoskeletal filaments that assemble at the inner face of plasma membrane. They localized constriction sites and impact membrane remodeling. We report in vitro tools to examine how yeast septins behave on curved deformable membranes. reshape membranes Giant Unilamellar Vesicles with formation periodic spikes, while flattening smaller vesicles. show deformations associated preferential arrangement septin specific curvatures. When binding bilayers supported custom-designed...
Abstract Filamentous biopolymer networks in cells and tissues are routinely imaged by confocal microscopy. Image analysis methods enable quantitative study of the properties these curvilinear networks. However, software tools to quantify geometry topology often dense 3D localize network junctions scarce. To fill this gap, we developed a new tool called “SOAX”, which can accurately extract centerlines identify using Stretching Open Active Contours (SOACs). It provides an open-source,...
In living cells, lipid membranes and biopolymers determine each other's conformation in a delicate force balance. Cellular polymers such as actin filaments are strongly confined by the plasma membrane cell protrusions lamellipodia filopodia. Conversely, protrusion formation is facilitated actin-driven deformation these maintained dense networks or bundles of filaments. Here we investigate mechanical interplay between bilayer reconstituting minimal model system based on cell-sized liposomes...
One challenge in cell biology is to decipher the biophysical mechanisms governing protein enrichment on curved membranes and resulting membrane deformation. The ERM ezrin abundant associated with cellular that are flat, positively or negatively curved. Using vitro approaches, we assess of ezrin’s membranes. We evidence wild-type (ezrinWT) its phosphomimetic mutant T567D (ezrinTD) do not deform but self-assemble anti-parallelly, zipping adjacent EzrinTD’s specific conformation reduces...
Abstract Cells remodel their cytoplasm with force-generating cytoskeletal motors. Their activity generates random forces that stir the cytoplasm, agitating and displacing membrane-bound organelles like nucleus in somatic germ cells. These are transmitted inside nucleus, yet consequences on liquid-like biomolecular condensates residing remain unexplored. Here, we probe experimentally computationally diverse nuclear condensates, include speckles, Cajal bodies, nucleoli, during cytoplasmic...
Filopodia are actin-rich membrane protrusions essential for cell morphogenesis, motility, and cancer invasion. How cells control filopodium initiation on the plasma remains elusive. We performed experiments in cellulo, vitro, silico to unravel mechanism of driven by curvature sensor IRSp53 (insulin receptor substrate protein 53 kDa). showed that full-length self-assembles into clusters membranes depending PIP2. Using well-controlled vitro reconstitution systems, we demonstrated recruit actin...
During HIV-1 particle formation, the requisite plasma membrane curvature is thought to be solely driven by retroviral Gag protein. Here, we reveal that cellular I-BAR protein IRSp53 required for progression of complete assembly. siRNA-mediated knockdown gene expression induces a decrease in viral production and bud arrest at half completion. Single-molecule localization microscopy cell shows preferential around assembly sites. In addition, observe presence purified particles. Finally,...
The endosomal sorting complexes required for transport (ESCRT) system is an ancient and ubiquitous membrane scission machinery that catalyzes the budding of membranes. ESCRT-mediated events, exemplified by those involved in HIV-1, are usually directed away from cytosol ("reverse topology"), but they can also be toward ("normal topology"). ESCRT-III subunits CHMP1B IST1 coat constrict positively curved tubes, suggesting these could catalyze normal topology severing. bind recruit...
Septin GTP-binding proteins contribute essential biological functions that range from the establishment of cell polarity to animal tissue morphogenesis. Human septins in cells form hetero-octameric septin complexes containing ubiquitously expressed SEPT9 subunit (also known as SEPTIN9). Despite established role mammalian development and human pathophysiology, biochemical biophysical studies have relied on monomeric SEPT9, thus not recapitulating its native assembly into complexes. We a...
Intracellular trafficking is mediated by transport carriers that originate membrane remodeling from donor organelles. Tubular contribute to the flux of lipids and proteins acceptor organelles, but how impose a tubular geometry on incompletely understood. Using imaging approaches cells in vitro systems, we show phosphatidylinositol-4-phosphate (PI4P) biogenesis lysosome-related organelles complex 1 (BLOC-1) govern formation, stability, functions recycling endosomal tubules. In vitro, BLOC-1...
Cytonemes are signaling filopodia that facilitate long-range cell-cell communication by forming synapses between cells. Initially discovered in Drosophila for transporting morphogens during embryogenesis, they have since been identified mammalian cells and implicated carcinogenesis. Despite their importance, mechanisms controlling cytoneme biogenesis remain elusive. Here, we demonstrate the Ser/Thr kinase Slik drives remote cell proliferation promoting formation. This function depends on...
The phosphoinositidyl lipid (PIP) family is key to spatial regulation of cellular processes, and their appearance, disappearance, interconversion provide signals for membrane remodeling at the plasma beyond. These are connected recruitment various peripheral proteins, including sorting nexin 9 (SNX9), an important regulator late stage endocytic macropinocytic remodeling. Using a combination live cell imaging, in vitro reconstitution, atomistic molecular dynamics simulation, we probe question...
Phosphatidylinositol phosphate (PIP) lipids, located on the inner leaflet of membrane facing cytoplasm, are key regulators a wide range cellular events at plasma membrane, in some cases by interacting with partner proteins that regulate actin assembly. Supported lipid bilayers (SLBs) have been recognized as powerful model to dissect mechanisms underlying clustering and interactions PIP lipids their proteins. However, despite advances methods generate SLBs, it remains challenge robustly...
The reshaping of the cell membrane is an integral part many cellular phenomena, such as endocytosis, trafficking, formation filopodia, etc. Many different proteins associate with curved membranes because their ability to sense or induce curvature. Typically, these processes involve a multitude making them too complex study quantitatively in cell. We describe protocol reconstitute vitro, mimicking structure, endocytic neck. A giant unilamellar vesicle (GUV) used model membrane, whose internal...
At the cell surface, actin cytoskeleton and plasma membrane interact reciprocally in a variety of processes related to remodeling surface. The has been known modulate organization reshape membrane. To this end, actin-membrane linking molecules play major role regulating assembly spatially direct interaction between While studies cells have provided wealth knowledge on molecular composition interactions interface, complex make it challenging elucidate precise actions linkers at interface....