A5087508718- Drug Transport and Resistance Mechanisms
- Advanced Electron Microscopy Techniques and Applications
- Glycosylation and Glycoproteins Research
- Nanopore and Nanochannel Transport Studies
- Cholesterol and Lipid Metabolism
- Lipid Membrane Structure and Behavior
- Trace Elements in Health
- ATP Synthase and ATPases Research
- Enzyme Structure and Function
- Nanoparticle-Based Drug Delivery
- Cancer therapeutics and mechanisms
- DNA and Nucleic Acid Chemistry
- Bacterial Genetics and Biotechnology
- Force Microscopy Techniques and Applications
- Ion channel regulation and function
- Pediatric Hepatobiliary Diseases and Treatments
- Galectins and Cancer Biology
- RNA and protein synthesis mechanisms
- Enzyme Production and Characterization
- Advanced NMR Techniques and Applications
- RNA Interference and Gene Delivery
- Hereditary Neurological Disorders
- Ion Transport and Channel Regulation
- Yersinia bacterium, plague, ectoparasites research
- Cancer, Lipids, and Metabolism
ETH Zurich
2017-2024
Holland Bloorview Kids Rehabilitation Hospital
2022-2023
Board of the Swiss Federal Institutes of Technology
2021
Institute of Molecular Biology and Biophysics
2018-2021
University of Basel
2009-2020
Jagiellonian University
2008
ABCB1, also known as P-glycoprotein, actively extrudes xenobiotic compounds across the plasma membrane of diverse cells, which contributes to cellular drug resistance and interferes with therapeutic delivery. We determined 3.5-angstrom cryo-electron microscopy structure substrate-bound human ABCB1 reconstituted in lipidic nanodiscs, revealing a single molecule chemotherapeutic compound paclitaxel (Taxol) bound central, occluded pocket. A second inhibited, human-mouse chimeric revealed two...
Significance ABCB1 is a membrane transport protein that protects cells from toxic compounds. At the same time, it limits uptake of orally administered drugs and contributes to multidrug resistance in cancer cells. Small-molecule inhibitors could alleviate these negative effects, but their development requires detailed insight into how such compounds interfere with ABCB1-catalyzed drug extrusion. Our study shows bind pairs can block function transporter by interacting structural features are...
The multidrug transporter ABCB1 (P-glycoprotein) is an ATP-binding cassette that has a key role in protecting tissues from toxic insult and contributes to extrusion cancer cells. Here, we report the near-atomic resolution cryo-EM structure of nucleotide-free trapped by engineered disulfide cross-link between nucleotide-binding domains (NBDs) bound antigen-binding fragment human-specific inhibitory antibody UIC2 third-generation inhibitor zosuquidar. Our reveals occluded conformation with...
Remember the sugar when making proteins Eukaryotes have an elaborate trafficking and quality-control system for secreted glycoproteins. The glycosylation pathway begins in endoplasmic reticulum with enzyme oligosaccharyltransferase (OST), which attaches a long chain of sugars to asparagine residues target proteins. Wild et al. report cryo-electron microscopy structure yeast OST, includes eight separate membrane central catalytic subunit contains binding sites substrates is flanked by...
The organic anion transporting polypeptides OATP1B1 and OATP1B3 are membrane proteins that mediate uptake of drugs into the liver for subsequent conjugation biliary excretion, a key step in drug elimination from human body. Polymorphic variants these transporters can cause reduced clearance adverse effects such as statin-induced rhabdomyolysis, co-administration OATP substrates lead to damaging drug-drug interaction. Despite their clinical relevance disposition pharmacokinetics, structure...
Injectisomes are multi-protein transmembrane machines allowing pathogenic bacteria to inject effector proteins into eukaryotic host cells, a process called type III secretion. Here we present the first three-dimensional structure of Yersinia enterocolitica and Shigella flexneri injectisomes in situ structural analysis injectisome. Unexpectedly, basal bodies inside bacterial cells showed length variations 20%. The structures Y. S. had similar dimensions were significantly longer than isolated...
A division of labor for glycosylation Glycosylation is a ubiquitous modification eukaryotic secreted proteins. Asparagine-linked chains sugars are appended to many substrates as they translocated into the endoplasmic reticulum. Ramírez et al. solved cryo–electron microscopy structures two human oligosaccharyltransferase complexes, OST-A and OST-B. The catalytic subunits bind partner proteins that direct specific either cotranslationally (OST-A) or on fully folded (OST-B). High-resolution...
ABCG2 is a multidrug transporter that affects drug pharmacokinetics and contributes to resistance of cancer cells. In previously reported structures, the reaction cycle was halted by absence substrates or ATP, mutation catalytic residues, presence small-molecule inhibitors inhibitory antibodies. Here we present cryo-EM structures under turnover conditions containing either endogenous substrate estrone-3-sulfate exogenous topotecan. We find two distinct conformational states in which both...
ABCG2 is an ATP-binding cassette (ABC) transporter whose function affects the pharmacokinetics of drugs and contributes to multidrug resistance cancer cells. While its interaction with endogenous substrate estrone-3-sulfate (E1S) has been elucidated at a structural level, recognition recruitment exogenous compounds not understood sufficiently high resolution. Here we present three cryo-EM structures nanodisc-reconstituted, human bound anticancer tariquidar, topotecan mitoxantrone. To enable...
Significance Structural studies of membrane proteins by cryogenic electron microscopy (cryo-EM) often require antibody fragments (Fabs) to facilitate particle alignments and achieve high resolution. While conformational nanobodies have been developed lock specific states many proteins, they only add 15 kDa mass the complex. We a synthetic Fab (NabFab) that rigidly binds conserved scaffold nanobodies, providing universally applicable fiducial for cryo-EM protein–nanobody complexes....
Nuclear factor κB (NF-κB) plays roles in various diseases. Many inflammatory signals, such as circulating lipopolysaccharides (LPSs), activate NF-κB via specific receptors. Using whole-genome CRISPR-Cas9 screens of LPS-treated cells that express an NF-κB-driven suicide gene, we discovered the LPS receptor Toll-like 4 (TLR4) is specifically dependent on oligosaccharyltransferase complex OST-A for N-glycosylation and cell-surface localization. The tool compound NGI-1 inhibits OST complexes...
Abstract Compact myelin comprises most of the dry weight myelin, and its insulative nature is basis for saltatory conduction nerve impulses. The major dense line (MDL) a 3-nm compartment between two cytoplasmic leaflets stacked membranes, mostly occupied by basic protein (MBP) phase. MBP an abundant involved in demyelinating diseases, such as multiple sclerosis. association with lipid membranes has been studied decades, but MBP-driven formation MDL remains elusive at biomolecular level. We...
Abstract Compact myelin forms the basis of nerve insulation essential for higher vertebrates. Dozens membrane bilayers undergo tight stacking, and in peripheral nervous system, this is partially enabled by protein zero (P0). Consisting an immunoglobulin (Ig)-like extracellular domain, a single transmembrane helix, cytoplasmic extension (P0ct), P0 harbours important task ensuring integrity compact compartment, referred to as intraperiod line. Several disease mutations resulting neuropathies...
ABCG2 is an ATP-binding cassette (ABC) transporter that extrudes a wide range of xenobiotics and drugs from the cell contributes to multidrug resistance in cancer cells. Following our recent structural characterization topotecan-bound ABCG2, here, we present cryo-EM structures under turnover conditions complex with special modulator slow substrate, tariquidar, nanodiscs. The reveal similar topotecan, tariquidar induces two distinct conformations (turnover-1 turnover-2). μs-scale molecular...
Cyclic nucleotide-modulated ion channels are important for signal transduction and pacemaking in eukaryotes. The molecular determinants of ligand gating these still unknown, mainly because a lack direct structural information. Here we report ligand-induced conformational changes full-length MloK1, cyclic potassium channel from the bacterium Mesorhizobium loti, analysed by electron crystallography atomic force microscopy. Upon cAMP binding, nucleotide-binding domains move vertically towards...
Abstract Nanodiscs offer a very promising tool to incorporate membrane proteins into native‐like lipid bilayers and an alternative liposomes maintain protein functions protein–lipid interactions in soluble nanoscale object. The activity of the incorporated appears be correlated its dynamics bilayer by interactions. These two parameters depend on internal surrounded lipid‐encircling discoidal scaffold that might differ from more unrestricted observed vesicles or cellular extracts. A...
BSEP (ABCB11) is an ATP-binding cassette transporter that expressed in hepatocytes and extrudes bile salts into the canaliculi of liver. dysfunction, caused by mutations or induced drugs, frequently associated with severe cholestatic liver disease. We report cryo-EM structure glibenclamide-bound human nanodiscs, revealing basis small-molecule inhibition. Glibenclamide binds apex a central binding pocket between transmembrane domains, preventing from undergoing conformational changes, thus...
ABCG1 is an ATP binding cassette (ABC) transporter that removes excess cholesterol from peripheral tissues. Despite its role in preventing lipid accumulation and the development of cardiovascular metabolic disease, mechanism underpinning ABCG1-mediated transport unknown. Here we report a cryo-EM structure human at 4 Å resolution inward-open state, featuring sterol-like density cavity. Structural comparison with multidrug ABCG2 sterol ABCG5/G8 reveals basis mechanistic differences distinct...