Biology subjects

Leistner, C.

Publications and source records attributed to Leistner, C..

3 recordsLinked to original sources

bioRxiv2026

Mechanism of membrane perforation in rotavirus cell entry

Cell entry of non-enveloped, animal viruses requires translocation of a macromolecular assembly across a cellular membrane. Double-stranded RNA viruses introduce into the target cell an inner capsid particle that does not uncoat further. Instead, it extrudes capped viral mRNA by virtue of polymerase and capping activities within it. As described here, we used cryogenic electron tomography to visualize the full course of rhesus rotavirus entry, from cell attachment and virion uptake to release of the subviral particle. The cryo-tomograms and subtomogram averaging of classified subparticles link high-resolution structures of the virion and its components with time series from live-cell fluorescence microscopy. We outlined the mechanism of each step in the entry process, including the membrane perforation step that transfers a subviral particle into the cytosol.

cell biology↗

bioRxiv2022

The in-tissue molecular architecture of β-amyloid pathology in the mammalian brain.

Amyloid plaques composed of extracellular focal deposition of A{beta} fibrils are a hallmark of Alzheimers disease (AD). Cryo-EM structures of A{beta} fibrils purified from human AD brain tissue post mortem have recently been determined. However, the molecular architecture of amyloid plaques in the context of fresh, unfixed mammalian brain tissue is unknown. Here, using cryogenic correlated light and electron tomography we report the native, in situ molecular architecture of A{beta} fibrils in the brain of a mouse model containing the Arctic familial AD mutation (AppNL-G-F) and an atomic model of Arctic A{beta} fibril purified from the brains of these animals. We show that in-tissue A{beta} fibrils are arranged in a lattice or in parallel bundles within a plaque, and are interdigitated by subcellular compartments, exosomes, extracellular droplets and extracellular multilamellar bodies. At the atomic level, the Arctic A{beta} fibril differs significantly from earlier structures of A{beta} amyloid extracted from AppNL-F mice models and human AD brain tissue, showing a striking effect of the Arctic mutation (E22G) on fibril structure. Cryo-electron tomography of ex vivo purified and in-tissue amyloid revealed an ensemble of additional fibrillar species, including thin protofilament-like rods and branched fibrils. Together, these results provide a structural model for the dense network architecture that characterises {beta}-amyloid plaque pathology.

neuroscience↗

bioRxiv2021

The molecular infrastructure of glutamatergic synapses in the mammalian forebrain

Glutamatergic synapses form the vast majority of connections within neuronal circuits, but how these subcellular structures are molecularly organized within the mammalian brain is poorly understood. Conventional electron microscopy using chemically fixed, metal- stained tissue has identified a proteinaceous, membrane-associated thickening called the postsynaptic density (PSD). Here, we combined mouse genetics and cryo-electron tomography to determine the 3D molecular architecture of fresh isolated and anatomically intact synapses in the adult forebrain. The native glutamatergic synapse did not consistently show a higher density of proteins at the postsynaptic membrane thought to be characteristic of the PSD. Instead, a synaptoplasm consisting of cytoskeletal elements, macromolecular complexes and membrane-bound organelles extended throughout the pre- and post- synaptic compartments. Snapshots of active processes gave insights into membrane remodeling processes. Clusters of up to 60 ionotropic glutamate receptors were positioned inside and outside the synaptic cleft. Together, these information-rich tomographic maps present a detailed molecular framework for the coordinated activity of synapses in the adult mammalian brain.

neuroscience↗