A5064689080- RNA and protein synthesis mechanisms
- RNA modifications and cancer
- RNA Research and Splicing
- Bacteriophages and microbial interactions
- Bacterial Genetics and Biotechnology
- Enzyme Structure and Function
- Genomics and Phylogenetic Studies
- Advanced Electron Microscopy Techniques and Applications
- Monoclonal and Polyclonal Antibodies Research
- Receptor Mechanisms and Signaling
- Chronic Lymphocytic Leukemia Research
- Glycosylation and Glycoproteins Research
- Phosphodiesterase function and regulation
- Retinal Development and Disorders
- Metalloenzymes and iron-sulfur proteins
- HIV Research and Treatment
- interferon and immune responses
- Biochemical Analysis and Sensing Techniques
- Neuropeptides and Animal Physiology
- SARS-CoV-2 and COVID-19 Research
- Hepatitis C virus research
- Mitochondrial Function and Pathology
- Cytomegalovirus and herpesvirus research
- vaccines and immunoinformatics approaches
- Immune Cell Function and Interaction
Charité - Universitätsmedizin Berlin
2015-2024
Freie Universität Berlin
2018-2024
Humboldt-Universität zu Berlin
2018-2024
Max Planck Institute for Molecular Genetics
2013-2023
Synaptic vesicles (SVs) fuse at a specialized membrane domain called the active zone (AZ), covered by conserved cytomatrix. How exactly cytomatrix components intersect with SV release remains insufficiently understood. We showed previously that loss of Drosophila melanogaster ELKS family protein Bruchpilot (BRP) eliminates (T bar) and declusters Ca2+ channels. In this paper, we explored additional functions cytomatrix, starting biochemical identification two BRP isoforms. Both isoforms...
Factor-dependent transcription termination mechanisms are poorly understood. We determined a series of cryo-electron microscopy structures portraying the hexameric adenosine triphosphatase (ATPase) ρ on pathway to terminating NusA/NusG-modified elongation complexes. An open ring contacts NusA, NusG, and multiple regions RNA polymerase, trapping locally unwinding proximal upstream DNA. NusA wedges into ring, initially sequestering RNA. Upon deflection distal DNA over polymerase zinc-binding...
Metal-containing formate dehydrogenases (FDH) catalyse the reversible oxidation of to carbon dioxide at their molybdenum or tungsten active site. They display a diverse subunit and cofactor composition, but structural information on these enzymes is limited. Here we report cryo-electron microscopic structures soluble Rhodobacter capsulatus FDH (RcFDH) as isolated in presence reduced nicotinamide adenine dinucleotide (NADH). RcFDH assembles into 360 kDa dimer heterotetramers revealing...
Abstract The melanocortin-4 receptor (MC4R), a hypothalamic master regulator of energy homeostasis and appetite, is class A G-protein-coupled prime target for the pharmacological treatment obesity. Here, we present cryo-electron microscopy structures MC4R–Gs-protein complexes with two drugs recently approved by FDA, peptide agonists NDP-α-MSH setmelanotide, 2.9 Å 2.6 resolution. Together signaling data from structure-derived MC4R mutants, complex reveal agonist-induced origin transmembrane...
The elongation of eukaryotic selenoproteins relies on a poorly understood process interpreting in-frame UGA stop codons as selenocysteine (Sec). We used cryo-electron microscopy to visualize Sec recoding in mammals. A complex between the noncoding Sec-insertion sequence (SECIS), SECIS-binding protein 2 (SBP2), and 40 S ribosomal subunit enables Sec-specific factor eEFSec deliver Sec. SBP2 do not interact directly but rather deploy their carboxyl-terminal domains engage with opposite ends...
Abstract Ribosome biogenesis is a fundamental multi-step cellular process in all domains of life that involves the production, processing, folding, and modification ribosomal RNAs (rRNAs) proteins. To obtain insights into still unexplored early assembly phase bacterial 50S subunit, we exploited minimal vitro reconstitution system using purified components scalable reaction conditions. Time-limited assays combined with cryo-EM analysis visualizes structurally complex pathway starting particle...
Translocation moves the tRNA2⋅mRNA module directionally through ribosome during elongation phase of protein synthesis. Although translocation is known to entail large conformational changes within both and tRNA substrates, orchestrated events that ensure speed fidelity this critical aspect synthesis mechanism have not been fully elucidated. Here, we present three high-resolution structures intermediates on mammalian where, in contrast bacteria, ribosomal complexes containing translocase eEF2...
Throughout the four phases of protein biosynthesis-initiation, elongation, termination, and recycling-the ribosome is controlled regulated by at least one specified translational guanosine triphosphatase (trGTPase). Although structural basis for trGTPase interaction with has been solved last three steps translation, high-resolution structure key initiation trGTPase, factor 2 (IF2), complexed ribosome, remains elusive. We determine IF2 a nonhydrolyzable triphosphate analog initiator...
Abstract In plant cells, translation occurs in three compartments: the cytosol, plastids and mitochondria. While structures of (prokaryotic-type) ribosomes mitochondria are well characterized, high-resolution eukaryotic 80S cytosol have been lacking. Here structure translating tobacco ( Nicotiana tabacum ) was solved by cryo-electron microscopy with a global resolution 2.2 Å. The ribosome includes two tRNAs, decoded mRNA nascent peptide chain, thus providing insights into molecular...
Structural studies of translating ribosomes traditionally rely on in vitro assembly and stalling defined states. To comprehensively visualize bacterial translation, we reactivated ex vivo-derived E. coli polysomes the PURE translation system analyzed actively elongating by cryo-EM. We find that 31% 70S assemble into disome complexes represent eight distinct functional states including decoding termination intermediates, a pre-nucleophilic attack state. The diversity together with RNase...
Abstract The surveillance of mRNA translation is imperative for homeostasis. Monitoring the integrity message essential, as aberrant mRNAs leads to stalling translational machinery. During ribosomal rescue, arrested ribosomes are specifically recognized by conserved eukaryotic proteins Dom34 and Hbs1, initiate their recycling. Here we solve structure Hbs1 bound a yeast ribosome programmed with nonstop at 3.3 Å resolution using cryo-electron microscopy. shows that Domain N inserted into...
Protein synthesis must be finely tuned in the developing nervous system as final essential step of gene expression. This study investigates architecture ribosomes from neocortex during neurogenesis, revealing Ebp1 a high-occupancy 60S peptide tunnel exit (TE) factor protein at near-atomic resolution by cryoelectron microscopy (cryo-EM). Ribosome profiling demonstrated Ebp1-60S binding is highest start codon initiation and N-terminal elongation, regulating ribosome occupancy these codons....
The Type III Secretion Systems (T3SS) needle complex is a conserved syringe-shaped protein translocation nanomachine with mass of about 3.5 MDa essential for the survival and virulence many Gram-negative bacterial pathogens. This system composed membrane-embedded basal body an extracellular that deliver effector proteins into host cells. High-resolution structures T3SS from different organisms infection stages are needed to understand underlying molecular mechanisms translocation. Here, we...
Among cyclic nucleotide phosphodiesterases (PDEs), PDE6 is unique in serving as an effector enzyme G protein-coupled signal transduction. In retinal rods and cones, membrane-bound activated to hydrolyse its substrate, cGMP, by binding of two active protein α-subunits (Gα*). To investigate the activation mechanism mammalian rod PDE6, we have collected functional structural data, analysed them reaction–diffusion simulations. Gα* titration reveals a strong asymmetry with respect affinity for...
Abstract Assembly of tailed bacteriophages and herpesviruses starts with formation procapsids (virion precursors without DNA). Scaffolding proteins (SP) drive assembly by chaperoning the major capsid protein (MCP) to build an icosahedral lattice. Here we report near-atomic resolution cryo-EM structures bacteriophage SPP1 procapsid, intermediate expanded procapsid partially released SPs, mature DNA. In state, SPs are bound only MCP pentons adjacent subunits from hexons. SP departure results...
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) Omicron variant sub-lineages spread rapidly worldwide, mostly due to their immune-evasive properties. This has put a significant part of the population at risk for disease and underscores need effective anti-SARS-CoV-2 agents against emergent strains in vulnerable patients. Camelid nanobodies are attractive therapeutic candidates high stability, ease large-scale production, potential delivery via inhalation. Here, we...