Temperature-Responsive Peptide–Nucleotide Coacervates

The Journal of Physical Chemistry B, Journal Year: 2021, Volume and Issue: 125(12), P. 3080 - 3091

Published: March 24, 2021

Coacervates are a type of liquid–liquid phase separated (LLPS) droplets that can serve as models membraneless organelles (MLOs) in living cells. Peptide–nucleotide coacervates have been widely used to mimic properties ribonucleoprotein (RNP) granules, but the thermal stability and role base stacking is still poorly understood. Here, we report systematic investigation formed by five different nucleoside triphosphates (NTPs) with poly-l-lysine poly-l-arginine function temperature. All studied combinations exhibit an upper critical solution temperature (UCST), temperature-dependent salt concentration, originating from significant nonelectrostatic contribution mixing free energy. Both enthalpic entropic parts this interaction decrease order G/A/U/C/T, accordance nucleobase energies. Partitioning two dyes proves local hydrophobicity inside peptide–nucleotide for every triphosphate. We derive simple relation between concentration at point based on mean-field model separation. Finally, when NTPs mixed one common oppositely charged peptide, hybrid were formed, characterized single intermediate UCST concentration. lower concentrations remain condensed far beyond their original Our results show NTP-based strong sensitivity due interactions significantly influence condensates and, extension, bioavailability.

Language: Английский

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Detecting and quantifying liquid–liquid phase separation in living cells by model-free calibrated half-bleaching

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: Dec. 16, 2022

Cells contain numerous substructures that have been proposed to form via liquid-liquid phase separation (LLPS). It is currently debated how reliably distinguish LLPS from other mechanisms. Here, we benchmark different methods using well-controlled model systems in vitro and living cells. We find 1,6-hexanediol treatment classical FRAP fail the alternative scenario of molecules binding spatially clustered sites without phase-separating. In contrast, preferential internal mixing seen half-bleach experiments robustly distinguishes both introduce a workflow termed model-free calibrated half-FRAP (MOCHA-FRAP) probe barrier at condensate interface responsible for mixing. use it study components heterochromatin foci, nucleoli, stress granules nuage granules, show strength interfacial increases this order. anticipate MOCHA-FRAP will help uncover mechanistic basis biomolecular condensates

Language: Английский

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Multifaceted Cargo Recruitment and Release from Artificial Membraneless Organelles

Small, Journal Year: 2022, Volume and Issue: 18(25)

Published: May 21, 2022

Abstract Liquid‐liquid phase separation (LLPS) drives membraneless organelles (MLOs) formation for organizing biomolecules. Artificial MLOs (AMLOs) have been constructed mostly via the LLPS of engineered proteins capable regulating limited types Here, leveraging a minimalist AMLO, driven by polymer‐oligopeptide hybrids, enrichment, recruitment, and release multifaceted cargoes are quantitatively shown, including small fluorescent molecules, fluorophore‐containing macromolecules, proteins, DNAs, RNAs. Cargoes show up to 10 5 ‐fold whilst recruitment triggered variations temperature, pH, and/or ionic strength. Also, first efficacious, rapid, reversible control aggregation‐induced emission with over 30 folds modulation overall fluorescence intensity is achieved, intensifying aggregation luminogens in AMLO. The AMLO simple yet versatile platform potential drug delivery biosensor applications.

Language: Английский

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Signal-processing and adaptive prototissue formation in metabolic DNA protocells

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: July 8, 2022

Abstract The fundamental life-defining processes in living cells, such as replication, division, adaptation, and tissue formation, occur via intertwined metabolic reaction networks that process signals for downstream effects with high precision a confined, crowded environment. Hence, it is crucial to understand reenact some of these functions wholly synthetic cell-like entities (protocells) envision designing soft materials life-like traits. Herein, we report on all-DNA protocells composed liquid DNA interior hydrogel-like shell, harboring catalytically active DNAzyme, converts into functional metabolites lead adaptation site-selective strand displacement reactions. include intra-protocellular phenotype-like changes, prototissue formation multivalent interactions, chemical messenger communication between sender dormant receiver cell populations sorted heteroprototissue formation. approach integrates several tools DNA-nanoscience synchronized way mimic behavior artificial systems future interactive materials.

Language: Английский

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Phase Transitions in Chemically Fueled, Multiphase Complex Coacervate Droplets

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(46)

Published: Sept. 6, 2022

Abstract Membraneless organelles are droplets in the cytosol that regulated by chemical reactions. Increasing studies suggest they internally organized. However, how these subcompartments remains elusive. Herein, we describe a complex coacervate‐based model composed of two polyanions and short peptide. With reaction cycle, control affinity peptide for polyelectrolytes leading to distinct regimes inside phase diagram. We study transitions from one regime another identify new can only occur under kinetic control. Finally, show cycle controls liquidity offering insights into active processes cells play an important role tuning liquid state membraneless organelles. Our work demonstrates not thermodynamic properties but also kinetics should be considered organization multiple phases droplets.

Language: Английский

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