Core‐Alkynylated Fluorescent Flippers: Altered Ultrafast Photophysics to Track Thick Membranes

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(31)

Published: May 17, 2024

Fluorescent flippers have been introduced as small-molecule probes to image membrane tension in living systems. This study describes the design, synthesis, spectroscopic and imaging properties of that are elongated by one two alkynes inserted between push pull dithienothiophene domains. The resulting mechanophores combine characteristics flippers, reporting on physical compression ground state, molecular rotors, torsional motion excited take their photophysics new level sophistication. Intensity ratios broadened excitation bands from differently twisted conformers core-alkynylated thus report mechanical compression. Lifetime boosts ultrafast excited-state planarization lifetime drops competitive intersystem crossing into triplet states viscosity. In standard lipid bilayer membranes, too long for leaflet tilt or extend disordered interleaflet space, which preserves rotor-like disorder weak, blue-shifted fluorescence. Flipper-like occurs only highly ordered membranes matching thickness, where they light up selectively these thick with red-shifted, sharpened maxima, high intensity lifetime.

Language: Английский

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Single-Molecule Localization Microscopy and Tracking with a Fluorescent Mechanosensitive Probe

The Journal of Physical Chemistry B, Journal Year: 2024, Volume and Issue: 128(33), P. 7997 - 8006

Published: Aug. 9, 2024

A milestone in optical imaging of mechanical forces cells has been the development family flipper fluorescent probes able to report membrane tension noninvasively living through their fluorescence lifetime. The specifically designed Flipper-CF3 probe with an engineered inherent blinking mechanism was recently introduced for super-resolution microscopy lipid ordered membranes but too dim be detected disordered at single-molecule level (García-Calvo, J. Am. Chem. Soc. 2020, 142(28), 12034–12038). We show here that original and commercially available Flipper-TR is compatible based resolves both liquid giant unilamellar vesicles below diffraction limit. Single molecules were additionally tracked bilayers, enabling distinguish varying composition from diffusion coefficient probe. Differences brightness between originate steady-state absorption properties. general compatibility scaffold detection further shown experiments targetable derivatives.

Language: Английский

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Fluorescent Membrane Probes Obey the Israelachvili Rules

Helvetica Chimica Acta, Journal Year: 2024, Volume and Issue: 107(7)

Published: May 9, 2024

Abstract When developing fluorescent membrane probes, we naturally tend to focus on the fluorophore itself. In this study, show that sometimes it can be beneficial shift attention from center periphery, maximize multiple interfacing with complex changing environments. Palmitylation for hydrophobic and glutamate dendrons hydrophilic are combined improve performance of flipper probes. We increase in membranes, solubility water is important, water, hydrophobicity probe. These seemingly paradoxical measures taken satisfy Israelachvili rules. They state only inverted cone amphiphiles form soluble micelles while shaped precipitate into hexagonal 1 supramolecular polymers, intermediate cylindrical behavior dominated by bilayers lamellar precipitates. The normal obtained prevent precipitation prepare efficient transfer lipid bilayer membranes. results flippers break all records set 2016 original regard effective brightness, responsiveness order, anchoring disordered partitioning membranes high stable labeling interest. lessons learned confirm obvious: rules apply also promise literally bright perspectives

Language: Английский

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Actin dynamics sustains spatial gradients of membrane tension in adherent cells

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: July 16, 2024

Abstract Tension propagates in lipid bilayers over hundreds of microns within milliseconds, precluding the formation tension gradients. Nevertheless, plasma membrane gradients have been evidenced migrating cells and along axons. Here, using a fluorescent probe, we show that exist all adherent cells, whether they migrate or not. Non-adhering do not display We further branched actin increases tension, while membrane-to-cortex attachments facilitate its propagation. is lowest at edge adhesion sites highest protrusions, setting boundaries By providing quantitative mechanistic basis behind organization gradients, our work explains how are actively sustained cells.

Language: Английский

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Core‐Alkynylated Fluorescent Flippers: Altered Ultrafast Photophysics to Track Thick Membranes

Angewandte Chemie, Journal Year: 2024, Volume and Issue: 136(31)

Published: May 17, 2024

Abstract Fluorescent flippers have been introduced as small‐molecule probes to image membrane tension in living systems. This study describes the design, synthesis, spectroscopic and imaging properties of that are elongated by one two alkynes inserted between push pull dithienothiophene domains. The resulting mechanophores combine characteristics flippers, reporting on physical compression ground state, molecular rotors, torsional motion excited take their photophysics new level sophistication. Intensity ratios broadened excitation bands from differently twisted conformers core‐alkynylated thus report mechanical compression. Lifetime boosts ultrafast excited‐state planarization lifetime drops competitive intersystem crossing into triplet states viscosity. In standard lipid bilayer membranes, too long for leaflet tilt or extend disordered interleaflet space, which preserves rotor‐like disorder weak, blue‐shifted fluorescence. Flipper‐like occurs only highly ordered membranes matching thickness, where they light up selectively these thick with red‐shifted, sharpened maxima, high intensity lifetime.

Language: Английский

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Asparagusic Golgi Trackers

JACS Au, Journal Year: 2024, Volume and Issue: 4(10), P. 3759 - 3765

Published: Aug. 20, 2024

Thiol-mediated uptake (TMU) is thought to occur through dynamic covalent cascade exchange networks. Here we show that the accounting for TMU of asparagusic acid derivatives (AspA) ends in Golgi apparatus (G) and shifts from disulfide thioester with palmitoyl transferases as final partner. As a result, AspA combined pH-sensitive fluoresceins, red-shifted silicon-rhodamines, or mechanosensitive flipper probes selectively labels fluorescence microscopy images living fixed cells. trackers work without cellular engineering excel speed, simplicity, generality, compatibility G/ER cis/trans discrimination, morphological changes, anterograde vesicular trafficking, superresolution imaging by stimulated emission depletion microscopy. flippers particular can image membrane order tension and, if desired, at plasma during TMU.

Language: Английский

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