A5088606060- Advanced Electron Microscopy Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- RNA and protein synthesis mechanisms
- Bacteriophages and microbial interactions
- Microbial infections and disease research
- Photosynthetic Processes and Mechanisms
- Advanced Fluorescence Microscopy Techniques
- RNA modifications and cancer
- Genomics and Chromatin Dynamics
- Genomics and Phylogenetic Studies
- Medical Image Segmentation Techniques
- Cell Image Analysis Techniques
- Computational Physics and Python Applications
- Streptococcal Infections and Treatments
- Lipid Membrane Structure and Behavior
- ATP Synthase and ATPases Research
- DNA Repair Mechanisms
- Bacterial Genetics and Biotechnology
- Pneumonia and Respiratory Infections
- Advanced X-ray Imaging Techniques
- Microtubule and mitosis dynamics
- Renal Diseases and Glomerulopathies
- Chromosomal and Genetic Variations
- Cellular Mechanics and Interactions
- Wnt/β-catenin signaling in development and cancer
Goethe University Frankfurt
2015-2024
Institute of Molecular Biology and Biophysics
2022
Max Planck Institute of Biophysics
2020
Institute of Molecular Biology
2020
University of Basel
2014
European Molecular Biology Laboratory
2006-2012
European Molecular Biology Laboratory
2005-2011
Frankfurt Institute for Advanced Studies
2011
European Molecular Biology Organization
2006-2010
European Bioinformatics Institute
2006-2008
Electron tomography of vitrified cells is a noninvasive three-dimensional imaging technique that opens up new vistas for exploring the supramolecular organization cytoplasm. We applied this to Dictyostelium cells, focusing on actin cytoskeleton. In networks reconstructed without prior removal membranes or extraction soluble proteins, cross-linking individual microfilaments, their branching angles, and membrane attachment sites can be analyzed. At resolution 5 6 nanometers, single...
Simply Mycoplasma The bacterium pneumoniae , a human pathogen, has genome of reduced size and is one the simplest organisms that can reproduce outside host cells. As such, it represents an excellent model organism in which to attempt systems-level understanding its biological organization. Now three papers provide comprehensive quantitative analysis proteome, metabolic network, transcriptome M. (see Perspective by Ochman Raghavan ). Anticipating what might be possible future for more complex...
Although the formation of 30-nm chromatin fibers is thought to be most basic event compaction, it remains controversial because high-resolution imaging in living eukaryotic cells had not been possible until now. Cryo-electron microscopy vitreous sections a relatively new technique, which enables direct observation cell structures close-to-native state. We used cryo-electron and image processing further investigate presence human mitotic chromosomes. HeLa S3 were vitrified by high-pressure...
Abstract Aims Coronavirus disease 2019 is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has emerged as a global pandemic. SARS-CoV-2 infection can lead to elevated markers of cardiac injury associated with higher risk mortality. It unclear whether direct cardiomyocytes or mainly secondary lung inflammation. Here, we investigate are permissive for infection. Methods results Two strains infected human induced pluripotent stem cell-derived demonstrated detection...
Abstract Cryo‐electron tomography analysis involves the selection of macromolecular complexes to be used for subsequent sub‐tomogram averaging and structure determination. Here, we describe a plugin developed UCSF ChimeraX that allows display, selection, editing particles within tomograms. Positions orientations selected can manually set, modified inspected in real time, both on screen virtual reality, exported various file formats. The parallel visualization stored several meta data lists,...
Electron tomograms of intact frozen-hydrated cells are essentially three-dimensional images the entire proteome cell, and they depict whole network macromolecular interactions. However, this information is not easily accessible because poor signal-to-noise ratio crowded nature cytoplasm. Here, we describe a template matching algorithm that capable detecting identifying macromolecules in tomographic volumes fully automated manner. The based on nonlinear cross correlation incorporates elements...
Evidence has accumulated recently that not only eukaryotes but also bacteria can have a cytoskeleton. We used cryo-electron tomography to study the three-dimensional structure of Spiroplasma melliferum cells in close-to-native state at approximately 4-nanometer resolution. showed these possess two types filaments arranged three parallel ribbons underneath cell membrane. These filamentous structures are built fibril protein and possibly actin-like MreB. On basis our structural data, we could...
Electron tomography is the only technique available that allows us to visualize three-dimensional structure of unfixed and unstained cells currently with a resolution 6–8 nm, but prospect reach 2–4 nm. This raises possibility detecting identifying specific macromolecular complexes within their cellular context by virtue structural signature. Templates derived from high-resolution molecule under scrutiny are used search reconstructed volume. Here we outline test computationally feasible...
Chromatin folding in eukaryotes fits the genome into limited volume of cell nucleus. Formation higher-order chromatin structures attenuates DNA accessibility, thus contributing to control essential functions such as transcription, replication, and repair. The 30-nm fiber is thought be first hierarchical level folding, but nucleosome arrangement compact was previously unknown. We used cryoelectron tomography vitreous sections determine structure compact, native avian erythrocyte nuclei....
Correlative microscopy incorporates the specificity of fluorescent protein labeling into high-resolution electron micrographs. Several approaches exist for correlative microscopy, most which have used green (GFP) as label light microscopy. Here we use chemical tagging and synthetic fluorophores instead, in order to achieve protein-specific labeling, perform multicolor imaging. We show that preserve their post-embedding fluorescence presence uranyl acetate. Post-embedding is such quality...
The cytoplasmic surface of intercellular junctions is a complex network molecular interactions that link the extracellular region desmosomal cadherins with cytoskeletal intermediate filaments. Although 3D structures major plaque components are known, overall architecture remains unknown. We used cryoelectron tomography vitreous sections from human epidermis to record images desmosomes in vivo and situ at resolution. Our results show desmosome 2D interconnected quasiperiodic lattice, similar...
Vertebrate life critically depends on renal filtration and excretion of low molecular weight waste products. This process is controlled by a specialized cell-cell contact between podocyte foot processes: the slit diaphragm (SD). Using comprehensive set targeted KO mice key SD molecules, we provided genetic, functional, high-resolution ultrastructural data highlighting concept flexible, dynamic, multilayered architecture SD. Our indicate that mammalian composed NEPHRIN NEPH1 while NEPH2 NEPH3...
We fabricated Pt-containing granular metals by focused electron beam–induced deposition from the (CH3)3CH3C5H4Pt precursor gas. The are made of platinum nanocrystallites embedded in a carbonaceous matrix. exposed as-grown nanocomposites to low-energy beam irradiation and measured electrical conductivity as function dose. Postgrowth transforms matrix microstructure thus strength tunneling coupling between Pt nanocrystallites. For samples (weak tunnel regime) we find that temperature...
A key event in cellular physiology is the decision between membrane biogenesis and fat storage. Phosphatidic acid (PA) an important intermediate at branch point of these pathways continuously monitored by transcriptional repressor Opi1 to orchestrate lipid metabolism. In this study, we report on mechanism recognition identify amphipathic helix (AH) for selective binding PA over phosphatidylserine (PS). The insertion AH into core renders sensitive acyl chain composition provides a means...