Recent Developments for the Deuterium and Tritium Labeling of Organic Molecules

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(6), P. 6634 - 6718

Published: Feb. 18, 2022

Organic compounds labeled with hydrogen isotopes play a crucial role in numerous areas, from materials science to medicinal chemistry. Indeed, while the replacement of by deuterium gives rise improved absorption, distribution, metabolism, and excretion (ADME) properties drugs enables preparation internal standards for analytical mass spectrometry, use tritium-labeled is key technique all along drug discovery development pharmaceutical industry. For these reasons, interest new methodologies isotopic enrichment organic molecules extent their applications are equally rising. In this regard, Review intends comprehensively discuss developments area over last years (2017–2021). Notably, besides fundamental isotope exchange (HIE) reactions isotopically analogues common reagents, plethora reductive dehalogenative deuteration techniques other transformations incorporation emerging now part labeling toolkit.

Language: Английский

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Deuterium in drug discovery: progress, opportunities and challenges

Nature Reviews Drug Discovery, Journal Year: 2023, Volume and Issue: 22(7), P. 562 - 584

Published: June 5, 2023

Language: Английский

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Caveat fluorophore: an insiders’ guide to small-molecule fluorescent labels

Nature Methods, Journal Year: 2021, Volume and Issue: 19(2), P. 149 - 158

Published: Dec. 23, 2021

Language: Английский

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Fixation can change the appearance of phase separation in living cells

eLife, Journal Year: 2022, Volume and Issue: 11

Published: Nov. 29, 2022

Fixing cells with paraformaldehyde (PFA) is an essential step in numerous biological techniques as it thought to preserve a snapshot of biomolecular transactions living cells. Fixed-cell imaging such immunofluorescence have been widely used detect liquid–liquid phase separation (LLPS) vivo. Here, we compared images, before and after fixation, expressing intrinsically disordered proteins that are able undergo LLPS. Surprisingly, found PFA fixation can both enhance diminish putative LLPS behaviors. For specific proteins, even cause their droplet-like puncta artificially appear do not any detectable the live condition. presence glycine, molecule modulates rates, reverse effect from enhancing diminishing appearance. We further established kinetic model context dynamic protein–protein interactions. Simulations based on suggest protein localization fixed depends intricate balance interaction dynamics, overall rate notably, difference between rates different proteins. Consistent simulations, live-cell single-molecule experiments showed fast relative dynamics minimize artifacts. Our work reveals changes appearance cells, presents caveat studying using fixation-based methods, suggests mechanism underlying artifact.

Language: Английский

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A general design of caging-group-free photoactivatable fluorophores for live-cell nanoscopy

Nature Chemistry, Journal Year: 2022, Volume and Issue: 14(9), P. 1013 - 1020

Published: July 21, 2022

Abstract The controlled switching of fluorophores between non-fluorescent and fluorescent states is central to every super-resolution fluorescence microscopy (nanoscopy) technique, the exploration radically new mechanisms remains critical boosting performance established, as well emerging methods. Photoactivatable dyes offer substantial improvements many these techniques, but often rely on photolabile protecting groups that limit their applications. Here we describe a general method transform 3,6-diaminoxanthones into caging-group-free photoactivatable fluorophores. These xanthones (PaX) assemble rapidly cleanly highly fluorescent, photo- chemically stable pyronine upon irradiation with light. strategy extendable carbon- silicon-bridged xanthone analogues, yielding family labels spanning much visible spectrum. Our results demonstrate versatility utility PaX in fixed live-cell labelling for conventional microscopy, coordinate-stochastic deterministic nanoscopies STED, PALM MINFLUX.

Language: Английский

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Dynamin is primed at endocytic sites for ultrafast endocytosis

Neuron, Journal Year: 2022, Volume and Issue: 110(17), P. 2815 - 2835.e13

Published: July 8, 2022

Dynamin mediates fission of vesicles from the plasma membrane during endocytosis. Typically, dynamin is recruited cytosol to endocytic sites, requiring seconds tens seconds. However, ultrafast endocytosis in neurons internalizes as quickly 50 ms synaptic vesicle recycling. Here, we demonstrate that 1 pre-recruited sites for Specifically, 1xA, a splice variant 1, interacts with Syndapin form molecular condensates on membrane. Single-particle tracking 1xA molecules confirms liquid-like property vivo. When mutated disrupt its interaction do not form, and consequently, slows down by 100-fold. Mechanistically, acts an adaptor binding stores at sites. This cache bypasses recruitment step accelerates synapses.

Language: Английский

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Structure and dynamics of the EGFR/HER2 heterodimer

Cell Discovery, Journal Year: 2023, Volume and Issue: 9(1)

Published: Feb. 13, 2023

HER2 belongs to the human epidermal growth factor receptor tyrosine kinase family. Its overexpression or hyperactivation is a leading cause for multiple types of cancers. functions mainly through dimerization with other family members, such as EGFR. However, molecular details heterodimer assembly have not been completely understood. Here, we report cryo-EM structures EGF- and epiregulin-bound EGFR/HER2 ectodomain complexes at resolutions 3.3 Å 4.5 Å, respectively. Together functional analyses, demonstrate that only arm HER2, but EGFR, essential their formation signal transduction. Moreover, analyze differential membrane dynamics transient interactions endogenous EGFR molecules in genome-edited cells using single-molecule live-cell imaging. Furthermore, show interaction could allow resist endocytosis. Together, this work deepens our understanding unique structural properties complex.

Language: Английский

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Chromatin expansion microscopy reveals nanoscale organization of transcription and chromatin

Science, Journal Year: 2023, Volume and Issue: 381(6653), P. 92 - 100

Published: July 6, 2023

Nanoscale chromatin organization regulates gene expression. Although is notably reprogrammed during zygotic genome activation (ZGA), the of regulatory factors this universal process remains unclear. In work, we developed expansion microscopy (ChromExM) to visualize chromatin, transcription, and transcription in vivo. ChromExM embryos ZGA revealed how pioneer factor Nanog interacts with nucleosomes RNA polymerase II (Pol II), providing direct visualization transcriptional elongation as string-like nanostructures. Blocking led more Pol particles clustered around Nanog, stalled at promoters Nanog-bound enhancers. This a new model termed "kiss kick", which enhancer-promoter contacts are transient released by elongation. Our results demonstrate that broadly applicable study nanoscale nuclear organization.

Language: Английский

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Quantitative analysis of autophagy reveals the role of ATG9 and ATG2 in autophagosome formation

The Journal of Cell Biology, Journal Year: 2023, Volume and Issue: 222(7)

Published: April 28, 2023

Autophagy is a catabolic pathway required for the recycling of cytoplasmic materials. To define mechanisms underlying autophagy it critical to quantitatively characterize dynamic behavior factors in living cells. Using panel cell lines expressing HaloTagged from their endogenous loci, we analyzed abundance, single-molecule dynamics, and autophagosome association kinetics proteins involved biogenesis. We demonstrate that formation inefficient ATG2-mediated tethering donor membranes key commitment step formation. Furthermore, our observations support model phagophores are initiated by accumulation on mobile ATG9 vesicles, ULK1 complex PI3-kinase form positive feedback loop Finally, duration biogenesis ∼110 s. In total, work provides quantitative insight into establishes an experimental framework analyze human

Language: Английский

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Chemical Approaches to Optimize the Properties of Organic Fluorophores for Imaging and Sensing

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(11)

Published: Dec. 12, 2023

Abstract Organic fluorophores are indispensable tools in cells, tissue and vivo imaging, have enabled much progress the wide range of biological biomedical fields. However, many available dyes suffer from insufficient performances, such as short absorption emission wavelength, low brightness, poor stability, small Stokes shift, unsuitable permeability, restricting their application advanced imaging technology complex imaging. Over past two decades, efforts been made to improve these performances fluorophores. Starting with luminescence principle fluorophores, this review clarifies mechanisms performance for traditional a certain extent, systematically summarizes modified approaches optimizing properties, highlights typical applications improved sensing, indicates existing problems challenges area. This not only proves significance improving but also provide theoretical guidance development high‐performance

Language: Английский

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