MINFLUX dissects the unimpeded walking of kinesin-1

Science, Journal Year: 2023, Volume and Issue: 379(6636), P. 1004 - 1010

Published: March 10, 2023

We introduce an interferometric MINFLUX microscope that records protein movements with up to 1.7 nanometer per millisecond spatiotemporal precision. Such precision has previously required attaching disproportionately large beads the protein, but requires detection of only about 20 photons from approximately 1-nanometer-sized fluorophore. Therefore, we were able study stepping motor kinesin-1 on microtubules at physiological adenosine-5′-triphosphate (ATP) concentrations. uncovered rotations stalk and heads load-free kinesin during showed ATP is taken a single head bound microtubule hydrolysis occurs when both are bound. Our results show quantifies (sub)millisecond conformational changes proteins minimal disturbance.

Language: Английский

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Live-cell imaging powered by computation

Nature Reviews Molecular Cell Biology, Journal Year: 2024, Volume and Issue: 25(6), P. 443 - 463

Published: Feb. 20, 2024

Language: Английский

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Understanding the cell: Future views of structural biology

Cell, Journal Year: 2024, Volume and Issue: 187(3), P. 545 - 562

Published: Feb. 1, 2024

Determining the structure and mechanisms of all individual functional modules cells at high molecular detail has often been seen as equal to understanding how work. Recent technical advances have led a flush high-resolution structures various macromolecular machines, but despite this wealth detailed information, our cellular function remains incomplete. Here, we discuss present-day limitations structural biology highlight novel technologies that may enable us analyze functions directly inside cells. We predict progression toward cell will involve shift conceptualizing 4D virtual reality using digital twins. These capture segments in highly enriched detail, include dynamic changes, facilitate simulations processes, leading experimentally testable predictions. Transferring biological questions into algorithms learn from existing data explore solutions ultimately unveil

Language: Английский

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Advancing cell biology with nanoscale fluorescence imaging: essential practical considerations

Trends in Cell Biology, Journal Year: 2024, Volume and Issue: 34(8), P. 671 - 684

Published: Jan. 5, 2024

Here, we provide an overview of the key factors to consider when using fluorescence nanoscopy (FN), including biological questions that can be addressed and aspects might improve reliability effectiveness FN experiments.We cover main related sample preparation, selection appropriate fixation, affinity-based labels, fluorescent dyes.We discuss current limitations possible future developments in field would facilitate a broader application FN.We multiplexing possibilities (allowing simultaneous detection multiple targets single experiment), live cell imaging for study cellular molecular dynamic processes, quantitative workflows. Recently, biologists have gained access several far-field (FN) technologies allow observation components with ~20 nm resolution. is revolutionizing biology by enabling visualization previously inaccessible subcellular details. While technological advances microscopy are critical field, optimal preparation labeling equally important often overlooked experiments. In this review, methodological experimental must considered performing FN. We present concepts dyes, multiplexing, approaches, microscopy. Consideration these greatly enhances FN, making it exquisite tool numerous applications. Conventional microscopy, widefield confocal has been essential studying morphology composition various organelles localization molecules. The resolution (see Glossary) techniques, usually above ~200 nm, limit macromolecular arrangements nanoscale structures. processes (<20 nm) major step forward because bridges world macromolecules. This effort facilitated recent decades use electron (EM), which provides morphological information at level [1.Winey M. et al.Conventional transmission microscopy.Mol. Biol. Cell. 2014; 25: 319-323Crossref PubMed Google Scholar] expenses limited identifications lack applicability. These overcome achieved resolving capabilities progressively reaching those attained EM. Several approaches based on enable researchers address <20 were difficult answer classical Paradigmatic examples applications include characterization periodicity actin rings synaptic sites neurons, structure nuclear pore complexes, maturation viral particles, organization mitochondrial cristae, mechanisms apoptosis, functioning signaling pathways [2.Fornasiero E.F. Opazo F. Super-resolution biologists.BioEssays. 2015; 37: 436-451Crossref Scholar]. Recent studies reached extremely high resolutions [3.Reinhardt S.C.M. al.Ångström-resolution microscopy.Nature. 2023; 617: 711-716Crossref Scopus (21) even enabled follow events such as stepping behavior kinesin vitro cells [4.Wolff J.O. al.MINFLUX dissects unimpeded walking kinesin-1.Science. 379: 1004-1010Crossref (20) Scholar,5.Deguchi T. al.Direct motor protein living MINFLUX.Science. 1010-1015Crossref (22) render individual molecules, GABA receptors, detail almost comparable cryo-EM [6.Shaib A.H. al.Visualizing proteins expansion microscopy.bioRxiv. (Published online March 10, 2023. https://doi.org/10.1101/2022.08.03.502284)Google compendium summarizes practical keep mind harnessing power nanoscopic biology. By bridging theory practice, roadmap researchers, equipping them know-how successfully navigate intricacies implementing, executing, deriving meaningful data from design experiments starts most suitable technique, each its own specific strengths (Figure 1A ; reviews different see [7.Jacquemet G. al.The biologist's guide super-resolution microscopy.J. Cell Sci. 2020; 133jcs240713Crossref (32) Scholar,8.Bond C. al.Technological processes.Mol. 2022; 82: 315-332Abstract Full Text PDF (25) Scholar]). Two strategies currently able reliably <20-nm samples: camera-based single-molecule (SMLM) [9.Rust M.J. al.Sub-diffraction-limit stochastic optical reconstruction (STORM).Nat. Methods. 2006; 3: 793-796Crossref (6072) minimal photon fluxes (MINFLUX) [10.Balzarotti al.Nanometer tracking molecules fluxes.Science. 2017; 355: 606-612Crossref (657) Based utilized perform on–off switching fluorophores required obtain super-resolved image, SMLM names; example, (STORM), photoactivated (PALM), DNA-points accumulation topography (DNA-PAINT) [11.Jungmann R. al.Single-molecule kinetics transient binding DNA origami.Nano Lett. 2010; 10: 4756-4761Crossref (576) addition two strategies, depending exact settings, stimulated emission depletion (STED) [12.Hell S.W. Wichmann J. Breaking diffraction emission: stimulated-emission-depletion microscopy.Opt. 1994; 19: 780Crossref achieve ~50 below, although laser not compatible conventional samples. technologies, approach aimed enlarging sample, then imaged either diffraction-limited or [13.Chen al.Optical imaging. Expansion microscopy.Science. 347: 543-548Crossref (858) With exception microcopy, specimens, opening avenue understanding dynamics native conditions (Box 1). Overall, four potential uncover as-yet unexplored detail. At same time, their capability requires protocols introduction artifacts tools linkage errors.Box 1Nanometer-scale cells: there yet?FN visualizes entire structures over time 'whole', allowing changes, recommended endoplasmic reticulum, chemical fixation introduces visible [19.Hoffman D.P. al.Correlative three-dimensional block-face whole vitreously frozen cells.Science. 367eaaz5357Crossref (33) our opinion, least connected implementation detailed herein.PhototoxicityPhototoxicity arises absorbed light generates free radicals reactive oxygen species, ultimately causing genomic damage, stress, degradation Figure 1D text). Light both endogenous additionally increase local temperature sample. To some effects, combinations image adaptive illumination [75.Heine al.Adaptive-illumination STED nanoscopy.Proc. Natl. Acad. U. S. A. 114: 9797-9802Crossref (0) Scholar], event-triggered emerging [76.Alvelid al.Event-triggered imaging.Nat. 1268-1275Crossref (15) Furthermore, novel fluorophore classes self-blinking dyes red photoswitchable exist, do require blue excited lower doses [77.Pennacchietti al.Fast reversibly photoswitching live-cell RESOLFT nanoscopy.Nat. 2018; 15: 601-604Crossref (58) Scholar].Low acquisition frequencyLow frequency resolution, but compromises interpretation fast processes. SMLM, limiting factor sufficient number while, scanning-based steps brightness size view. Reducing view spent pixel (dwell time) speed up imaging, decreased contextual SNR. will strongly benefit parallelization deep learning temporal performances.Availability impact cellsThe availability cannot ignored. Some probes drugs bind target affinity, interfering physiology targeted molecule (e.g., phalloidin). An alternative genetically encoded tags or, better, combined genome-editing [78.Bottanelli al.A physiological role ARF1 formation bidirectional tubules Golgi.Mol. 28: 1676-1687Crossref Table 1 text).Imaging depth large viewImaging many samples monolayers. Although feasibility specialized demonstrated [79.Kim al.Oblique-plane tissues small intact animals.Nat. 2019; 16: 853-857Crossref (54) deeper than 10–50 μm methods challenging. engineered illumination, optics, restoration algorithms, multiphoton excitation.Ultimately, best technology selected setup precise question being addressed, controls phototoxic cause damage considered. should done settings less perturbation troubleshooting conditions. For far-red commonly used compared 405-laser irradiance. herein. Phototoxicity Low performances. Availability Imaging excitation. Ultimately, short 'no', all problems solved. Careful consideration given whether necessary questions. determine interest (POI) localized lysosomes mitochondria, POI outer membrane inner matrix, apart. general, strength increased precision biomolecules 1B,C). A simple rule thumb decide needed understand spatial order tens nanometers allows formulation fundamentally hypotheses process under investigation. serendipitous observations made and, cases, revealed new observable [14.Xu K. al.Actin, spectrin, associated form periodic cytoskeletal axons.Science. 2013; 339: 452-456Crossref (888) reason, exploratory Very high-resolution informative, could ignored become challenges Live ultimate goal studies, still due phototoxicity early stage foreseeable relevant near future. fixed already changing field; therefore, concentrate here specimens 1D–F). workflow 'non-live' first optimized avoid artifacts. After antibodies, reveal identities position reporter proximity. relative absolute biologically numbers images (quantitative FN), further measures considerations taken. Box 2, review issues explain why density, stoichiometry, error context. Finally, 3, conditions.Box 2Quantitative FN: versus observed moleculesQuantitative detected matches (or, more precisely, correlates) real Therefore, prerequisites controlled efficiency ability detect fluorophores.A monovalent affinity carrying (or of) reporting 2A Moreover, utilize covalently linked ensure stably labeled preferred. multivalent polyclonal reagents stochastically secondary antibodies approximately one six fluorophores) avoided since correlation between reporters inconsistent.Even ideal case decorated label, possibility exists only decorating label functional. Indeed, inactivated, damaged, during procedure 1E Detecting densely challenging, problem known crowding. When distances single-digit nanometer scale, photophysical interactions occur, resulting undesired alterations properties. happens structure, Förster resonance energy transfer (FRET) H-dimer if separated molecular-scale [80.Ogawa al.H-Type dimer fluorophores: mechanism activatable, vivo imaging.ACS Chem. 2009; 4: 535-546Crossref (153) Notably, reported antibody [81.Helmerich D.A. al.Multiple-labeled behave like emitters buffer.ACS Nano. 14: 12629-12641Crossref (13) serving 'super emitter' while others remain dark state. crowding reversed, physically creating distance Other DNA-PAINT, deal differently modulating concentration probe light-controllable [82.Raymo F.M. Photoactivatable synthetic nanoscale.J. Phys. 2012; 2379-2385Crossref (60) 2D text).While quantification easily achieved, molecule-counting proposed comprehensive recently published challenge [83.Hugelier al.Quantitative microscopy.Annu. Rev. Biophys. 52: 139-160Crossref (1) Importantly, need calibration benchmarked against markers biochemically western blot, liquid chromatography, mass spectrometry).Box 3Fluorophore no one-size-fits-all solutionsA variety developed fulfill requirement technique (Table I). Factors selecting charge, quantum yield, photostability 2C photostable fluorophores, MINFLUX rely switch non-emitting emitting states. mechanisms, refer reader text.The scaffolds cyanines rhodamines. Among cyanines, Alexa Fluor 647 gold standard blinks presence reducing agents UV [84.Berlier J.E. comparison long-wavelength Cy Dyes: bioconjugates.J. Histochem. Cytochem. 2003; 51: 1699-1712Crossref (229) Rhodamines relatively modified tune spectral properties [85.Grimm J.B. general method optimize functionalize red-shifted rhodamine dyes.Nat. 17: 815-821Crossref (85) permeability [86.Lukinavičius near-infrared proteins.Nat. 5: 132-139Crossref (648) equilibrium open closed non-fluorescent forms. regulation latter induces cell-compatible spontaneous blinking Scholar].Other frequently coumarin, oxazine, BODIPY 2E Coumarins among smallest generate variants Stokes shift, advantageous low background [87.Nizamov al.Phosphorylated 3-heteroarylcoumarins nanoscopy.Chem. Eur. 18: 16339-16348Crossref (45) Oxazines [88.Wombacher al.Live-cell trimethoprim conjugates.Nat. 7: 717-719Crossref (282) absorbance, extinction coefficient, 'blink' buffers containing oxidizing agents. valued sharp absorption spectra very yield coefficient [89.Kowada al.BODIPY-based cells.Chem. Soc. 44: 4953-4972Crossref highly hydrophobic nature poor off-switching properties, light-dose photoactivatable make attractive [90.Wijesooriya C.S. localization-based imaging.Angew. Int. Ed. 57 (12685–1268)Crossref (74) Scholar].In after identified, always considering specifications available instrument lasers detectors). choice also driven needs, multicolor autofluorescence reduce background, counting naked may themselves affinities lipophilic stain membranes). evaluated designing experiments, (reporters) without targeting moiety whenever 2B recommend inexperienced users consult expert select dye application.Table IProperties dyesFluorophore classCoumarinsRhodaminesCyaninesBODIPYsOxazinesCommercial examplesAlexa 350, Pacific BlueAlexa 488, silicon-rhodamine, TMRAlexa 647, 555, Cy5BODIPY FL, TMRAtto 655, Atto 680Spectral range (nm)360–700500–750500–1000500–700600–750Extinction (cm–1M–1)15 000–60 00080 000–150 000130 000–250 00060 000–100 000110 000–130 000Quantum yield0.4–0.90.1–0.90.1–0.60.8–0.90.1–0.6Photostability+++++++++++Compatibility methodsSTED, SMLMSTED, MINFLUX, microscopySTED, SMLMSMLM Open table tab Quantitative fluorophores. inconsistent. Even sin

Language: Английский

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Transcription Factor Dynamics: One Molecule at a Time

Annual Review of Cell and Developmental Biology, Journal Year: 2023, Volume and Issue: 39(1), P. 277 - 305

Published: Aug. 4, 2023

Cells must tightly regulate their gene expression programs and yet rapidly respond to acute biochemical biophysical cues within environment. This information is transmitted the nucleus through various signaling cascades, culminating in activation or repression of target genes. Transcription factors (TFs) are key mediators these signals, binding specific regulatory elements chromatin. While live-cell imaging has conclusively proven that TF-chromatin interactions highly dynamic, how such transient can have long-term impacts on developmental trajectories disease progression still largely unclear. In this review, we summarize our current understanding dynamic nature TF functions, starting with a historical overview early experiments. We highlight govern dynamics dynamics, turn, affect downstream transcriptional bursting. Finally, conclude open challenges emerging technologies will further regulation.

Language: Английский

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Oligomeric organization of membrane proteins from native membranes at nanoscale spatial and single-molecule resolution

Nature Nanotechnology, Journal Year: 2023, Volume and Issue: 19(1), P. 85 - 94

Published: Nov. 27, 2023

Language: Английский

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Heterogeneous anomalous transport in cellular and molecular biology

Reports on Progress in Physics, Journal Year: 2023, Volume and Issue: 86(12), P. 126601 - 126601

Published: Oct. 20, 2023

It is well established that a wide variety of phenomena in cellular and molecular biology involve anomalous transport e.g. the statistics for motility cells molecules are fractional do not conform to archetypes simple diffusion or ballistic transport. Recent research demonstrates many cases heterogeneous both time space. Thus single exponents generalised coefficients unable satisfactorily describe crucial biology. We consider advances field ofheterogeneous transport(HAT) highlighting: experimental techniques (single molecule methods, microscopy, image analysis, fluorescence correlation spectroscopy, inelastic neutron scattering, nuclear magnetic resonance), theoretical tools data analysis (robust statistical methods such as first passage probabilities, survival different varieties mean square displacements, etc), analytic theory generative models based on simulations. Special emphasis made high throughput machine learning neural networks. Furthermore, we context microrheology viscoelasticity complex fluids. HAT wavefronts reaction-diffusion systems also considered since it plays an important role morphogenesis signalling. In addition, present specific examples from including embryonic cells, leucocytes, cancer bacterial biofilms, eukaryotic microorganisms. Case studies include DNA, membranes, endosomal transport, endoplasmic reticula, mucins, globular proteins, amyloids.

Language: Английский

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Super-resolved FRET and co-tracking in pMINFLUX

Nature Photonics, Journal Year: 2024, Volume and Issue: 18(5), P. 478 - 484

Published: Feb. 9, 2024

Language: Английский

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Single-Molecule Spectroscopy and Super-Resolution Mapping of Physicochemical Parameters in Living Cells

Annual Review of Physical Chemistry, Journal Year: 2024, Volume and Issue: 75(1), P. 163 - 183

Published: Feb. 16, 2024

By superlocalizing the positions of millions single molecules over many camera frames, a class super-resolution fluorescence microscopy methods known as single-molecule localization (SMLM) has revolutionized how we understand subcellular structures past decade. In this review, highlight emerging studies that transcend outstanding structural (shape) information offered by SMLM to extract and map physicochemical parameters in living mammalian cells at levels. encoding/decoding high-dimensional information-such emission excitation spectra, motion, polarization, lifetime, beyond-for every molecule, mass accumulating these measurements for molecules, such multidimensional multifunctional approaches open new windows into intracellular architectures dynamics, well their underlying biophysical rules, far beyond diffraction limit.

Language: Английский

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Using an ER-specific optogenetic mechanostimulator to understand the mechanosensitivity of the endoplasmic reticulum

Developmental Cell, Journal Year: 2024, Volume and Issue: 59(11), P. 1396 - 1409.e5

Published: April 2, 2024

The ability of cells to perceive and respond mechanical cues is essential for numerous biological activities. Emerging evidence indicates important contributions organelles cellular mechanosensitivity mechanotransduction. However, whether how the endoplasmic reticulum (ER) senses reacts forces remains elusive. To fill knowledge gap, after developing a light-inducible ER-specific mechanostimulator (LIMER), we identify that mechanostimulation ER elicits transient, rapid efflux Ca2+ from in monkey kidney COS-7 cells, which dependent on cation channels transient receptor potential channel, subfamily V, member 1 (TRPV1) polycystin-2 (PKD2) an additive manner. This release can be repeatedly stimulated tuned by varying intensity duration force application. Moreover, inhibits ER-to-Golgi trafficking. Sustained mechanostimuli increase levels binding-immunoglobulin protein (BiP) expression phosphorylated eIF2α, two markers stress. Our results provide direct tight mechanoregulation functions, placing as player intricate map

Language: Английский

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