Visualizing HIV-1 Assembly at the T-Cell Plasma Membrane Using Single-Molecule Localization Microscopy.

The 20-year revolution in optical fluorescence microscopy, supported by the optimization of both spatial resolution and timely acquisition, allows the visualization of nanoscaled objects in cell biology. Currently, the use of a recent generation of super-resolution fluorescence microscope coupled with improved fluorescent probes gives the possibility to study the replicative cycle of viruses in living cells, at the single-virus particle or protein level. Here, we highlight the protocol for visualizing HIV-1 Gag assembly at the host T-cell plasma membrane using super-resolution light microscopy.

Label-Free Single Nanoparticle Identification and Characterization in Demanding Environment, Including Infectious Emergent Virus.

Unknown particle screening-including virus and nanoparticles-are keys in medicine, industry, and also in water pollutant determination. Here, RYtov MIcroscopy for Nanoparticles Identification (RYMINI) is introduced, a staining-free, non-invasive, and non-destructive optical approach that is merging holographic label-free 3D tracking with high-sensitivity quantitative phase imaging into a compact optical setup. Dedicated to the identification and then characterization of single nano-object in solution, it is compatible with highly demanding environments, such as level 3 biological laboratories, with high resilience to external source of mechanical and optical noise.

HIV-1 diverts cortical actin for particle assembly and release.

Enveloped viruses assemble and bud from the host cell membranes. Any role of cortical actin in these processes have often been a source of debate. Here, we assessed if cortical actin was involved in HIV-1 assembly in infected CD4 T lymphocytes.

Quantifying membrane binding and diffusion with fluorescence correlation spectroscopy diffusion laws.

Many transient processes in cells arise from the binding of cytosolic proteins to membranes. Quantifying this membrane binding and its associated diffusion in the living cell is therefore of primary importance. Dynamic photonic microscopies, e.

Extracellular vesicles containing the I-BAR protein IRSp53 are released from the cell plasma membrane in an Arp2/3 dependent manner.

Backgroud: Extracellular vesicles (EVs) are nanometric membrane vesicles produced by cells and involved in cell-cell communication. EV formation can occur in endosomal compartments whose budding depends on the ESCRT machinery (i.e.

Illuminating the nanoscopic world of viruses by fluorescence super-resolution microscopy.

The recent revolution in optical fluorescence microscopy, supported by the optimization of both spatial resolution and acquisition speed, led to the ability to visualize nano-scaled objects. Currently, the use of a new generation of super-resolution fluorescence microscopes coupled to improved fluorescent probes gives the possibility to study the replicative cycle of viruses in living cells, at the single-virus and molecule level. In this review, after a brief chronological description of these new approaches, we highlight several examples of super-resolution microscopies that have allowed to revisit our understanding of several human viruses and of host-pathogen interactions.

[Illuminating the nanoscopic world of viruses by fluorescence super-resolution microscopy].

The recent revolution in optical fluorescence microscopy, supported by the optimization of both spatial resolution and acquisition speed, led to the ability to visualize nano-scaled objects. Currently, the use of a new generation of super-resolution fluorescence microscopes coupled to improved fluorescent probes gives the possibility to study the replicative cycle of viruses in living cells, at the single-virus and molecule level. In this review, after a brief chronological description of these new approaches, we highlight several examples of super-resolution microscopies that have allowed to revisit our understanding of several human viruses and of host-pathogen interactions.