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Many biological systems appear to organize their dynamics close to a critical point. Now it is shown that the protein array mediating Escherichia coli chemosensing is near-critical, enabling large signal amplification without compromising response speeds.

Different agonists produce equilibria of at least four distinct active states of the G-protein-bound M2 muscarinic acetylcholine receptor, each with a different ability to activate G proteins.

Tracers are fluorescent protein ligands required for various displacement assays. Here, the authors announce a curated database named tracerDB, which will make essential tracer data, contributed by the worldwide research community, easily available and searchable.

Some transcription factors can organize into different structural states, from small nanoscale clusters to macrophases. Here authors show that NHA9 undergoes differential conformational expansion across these states and exhibits micelle-like organization with non-fixed stoichiometry.

A multi-laboratory study finds that single-molecule FRET is a reproducible and reliable approach for determining accurate distances in dye-labeled DNA duplexes.

Mechanical forces at the immunological synapse are believed to influence antigen recognition by the T cell receptor (TCR). Here the authors analyse these forces at single-molecule resolution to show that the ligand-engaged TCR of CD4+ T-cells create a stable environment with only a small fraction of TCR:pMHC complexes experiencing mechanistic forces at any given time during antigen surveillance and upon T-cell activation.

Higher-order TCRs have been postulated to maintain high antigen sensitivity and trigger signaling. Huppa and colleagues use various investigative techniques and find exclusively monomeric TCR–CD3 complexes that drive the recognition of antigenic pMHC.

Previously shown as a 60-nm hole in the nuclear pore complex, the transport machinery by FG-nucleoporins is mapped.

Far-red kinase biosensors are applied to image kinase signaling networks at super resolution.

Nonhomologous end joining (NHEJ), the primary pathway of vertebrate DNA double strand-break (DSB) repair, directly re-ligates broken DNA ends with minimal errors. In this study, the authors identify structural interactions of the NHEJ-specific DNA Ligase IV (Lig4) that prioritize ligation and promote NHEJ fidelity.

Hsp90 is a molecular chaperone important for protein homeostasis. Here, the authors show that the conformational transitions during the Hsp90 ATPase cycle are conserved from yeast to humans, but a few mutations alter cycle timing and dynamics.

Mechanical forces acting on ligand-engaged T-cell receptors (TCRs) have previously been implicated in T-cell antigen recognition, yet their sensitivity and specificity are still poorly defined. Here, authors report a FRET-based sensor that informs directly on the magnitude and kinetics of TCR-imposed forces at the single molecule level.

Quasicrystalline materials exhibit long-range order but no translational periodicity. Now, a random tiling quasicrystal has been fabricated on a Au(111) surface by coordination interactions between europium centres and linear dicarbonitrile linkers under stoichiometry control. The 2D metal–organic network exhibits the simultaneous presence of four-, five- and six-fold vertices and dodecagonal symmetry.

Small heat shock proteins (sHsps) form large spherical assemblies and their regulation is not well understood. Here, the authors provide insights into the mechanism of Hsp26 activation by characterising phospho-mimetic mutants of yeast Hsp26. They present cryo-EM structures of the wild-type Hsp26 40mer and its phospho-mimetic mutants that reveal the location of the thermosensor in the oligomer, and the authors also show that the thermosensor domain is targeted by phosphorylation, which relieves the intrinsic inhibition of chaperone activity.

How p97 processes diverse clients has remained controversial. van den Boom, Kueck and colleagues now demonstrate that p97 recognizes an internal segment of the PP1 partner I3 and then threads an I3 peptide loop through the channel in p97 to strip I3 off PP1.

An international blind study confirms that smFRET measurements on dynamic proteins are highly reproducible across instruments, analysis procedures and timescales, further highlighting the promise of smFRET for dynamic structural biology.

Photoactive transition metal complexes usually feature 4d6 and 5d6 precious metals with charge transfer excited state lifetimes exceeding hundreds of nanoseconds, while complexes with earth abundant 3d6 metals exhibit lifetimes of less than 1–2 ns. Here, the authors report a tetracarbene manganese(I) complex with an excited state lifetime of 190 ns.

The chaperones Hsp70 and Hsp90 are physically linked via the cochaperone Sti1/Hop, that has two binding sites for Hsp70. Here, Röhl et al.show that binding of Hsp90 changes the conformation of Sti1/Hop and determines to which site Hsp70 binds, perhaps facilitating transfer of client proteins from Hsp70 to Hsp90.

In addition to national climate targets, the authors estimate countries’ additional accountability to stay within the 1.5-degree carbon budget. They account for G7 countries having the highest carbon debts while several BRICS+ countries have high future claims.

In eukaryotes, dynamins and dynamin-like proteins (DLPs) are involved in various membrane remodeling processes. Here, the authors present the structure and functional characterization of a DLP of the cyanobacterium Synechocystis sp. PCC 6803.

P450 oxidoreductase (POR) selectively activates numerous cytochromes P450 (CYP), crucial for metabolism of drugs, steroids and xenobiotics and natural product biosynthesis. Here, the authors identify ligands that bind POR and bias its specificity towards CYP redox partners, activating distinct metabolic cascades in cells.

Here, the authors characterize the gut plasmidome of a cohort of 34 mother-infant dyads showing that infants exhibit greater plasmid diversity compared to their mothers and other healthy adults, with Bacteroidota representing the primary host for gut plasmids and plasmid transfer.

Convection shapes BVOC dynamics over the Amazon rainforest, driving dawn photochemistry in the upper troposphere. Changes in BVOC emissions can strongly impact regional and global atmospheric chemistry.

Sulfonylureas are widely used anti-diabetic drugs, which promote insulin release by blocking a pancreatic ion channel. Here the authors create a photoswitchable sulfonylurea derivative and use it to control insulin release from cultured cells and isolated pancreatic islets by illumination with blue light.

NMR and Raman spectroscopies pinpoint the role of the protein droplet surface and RNA in the liquid droplet maturation mechanism of the FUS protein. A crust-like β-sheet structure is formed on the surface of FUS droplets during aging.

Single-particle tracking PALM (sptPALM) provides quantitative information in vivo if the protein of interest remains in a single diffusional state during track acquisition. Here the authors develop a custom-built sptPALM microscope and a Monte-Carlo based diffusion distribution analysis to study dynamic DNA-dCas9 interactions in live bacteria.

The realization of efficient light–matter interfaces is important for many quantum technologies. An experiment now shows how to coherently switch the collective optical properties of an array of quantum emitters by driving a single ancilla atom to a Rydberg state.

Olfactory perception shows marked sexual dimorphism, yet its genetic basis remains underexplored. Here, the authors show sex-specific and shared genetic loci for odour identification, implicating olfactory receptor clusters and links to Alzheimer’s disease risk.

The authors discuss the physics underlying the enhancement of energy transfer and energy transport in molecular systems and identify key questions and theoretical challenges for future research.

The ability to infer quantitative kinetic information from single-molecule FRET (smFRET) data can be challenging. Here the authors perform a blind benchmark study assessing different analysis tools used to infer kinetic rate constants from smFRET trajectories, testing on simulated and experimental data.

A computational model generates conformational ensembles of 28,058 intrinsically disordered proteins and regions (IDRs) in the human proteome and sheds light on the relationship between sequence, conformational properties and functions of IDRs.

The commercialisation of organic photovoltaic technology calls for research on material degradation mechanisms. Ramirez et al. show that triplet excitons produced by back charge transfer can significantly impact the photo-stability of fullerene-based devices even in the absence of water and oxygen.

S. cerevisiae encodes two Hsp90 isoforms, the constitutively expressed Hsc82 and stress-inducible Hsp82 that are 97% identical. Here, the authors combine a range of biophysical methods and show that they differ in their enzymatic properties, resilience to stress and client range, which suggests that they evolved to provide fine-tuned chaperone assistance under physiological and stress conditions.

Cell movements are achieved by the spatio-temporal coordination of local membrane protrusions and retractions. Here, the authors identify a mechanism by which these protrusion and retraction events are coupled and how this affects the directionality of cell movements.

A tectothalamic pathway for social affiliation in developing zebrafish dissociates neuronal control of attraction from repulsion during affiliation, revealing a circuit underpinning of collective behaviour

It has been commonly believed that the driving force at the donor-acceptor heterojunction is vital to efficient charge separation in organic solar cells. Here Zhong et al. show that the driving force can be as small as 0.05 eV without compromising the charge transfer rate and efficiency.

The role of co-chaperone and Hsp90 activator Aha1 is now examined in conjunction with other co-chaperones in vivo and in vitro, to reveal how they regulate the progression of the Hsp90 cycle. Aha1 and Cpr6 interact with and activate Hsp90 in a synergistic manner and displace the inhibitory co-chaperone Sti1. Aha1 is eventually released from Hsp90 by p23.

The Hsp90 chaperone is responsible for the stabilization of a large variety of regulatory proteins. By labeling the subunits in the Hsp90 homodimer with different dyes and in different positions, the kinetics of Hsp90 conformational changes along the ATPase cycle was characterized, revealing different intermediate states and the different roles of cochaperones.

The chaperone Hsp90 uses the free energy from ATP hydrolysis to control the folding of client proteins in eukaryotic cells. Here the authors provide mechanistic insights into how its catalytic activity is coupled to conformational changes by combining large-scale molecular simulations with NMR, FRET and SAXS experiments.

Auxiliary AMPA receptor subunits can affect gating and surface mobility. Here the authors show that Shisa6 traps AMPA receptors at postsynaptic sites via PSD-95, and keeps them in an activated state in the presence of glutamate, preventing full desensitization and consequently synaptic depression.

Experiments show that when driven by electric currents, magnetic skyrmions experience transverse motion due to their topological charge — similar to the conventional Hall effect experienced by charged particles in a perpendicular magnetic field.

The signalling events leading to insulin release from β-cells are tightly controlled and new techniques are needed to understand the complicated interactions. This Review discusses new optical tools available to further our understanding of β-cell function and insulin release.

Single-molecule imaging of nonhomologous end joining in Xenopus egg extract reveals that a single XLF dimer aligns broken DNA ends for ligation.

BiP is an Hsp70 chaperone in the endoplasmic reticulum (ER) and is crucial for protein folding and quality control. Using single-molecule and ensemble FRET, the conformational cycle of BiP has now been defined. Movement of the lid domain of BiP allows this chaperone to discriminate between peptide and protein substrates.

The ER-resident Hsp70 BiP is regulated by NEF Bap. The interactions between BiP and Bap are now dissected using biochemistry, molecular modeling and smFRET approaches, revealing that Bap affects both domains of BiP, to coordinate release of substrate and nucleotide.

Molecular mechanisms by which glucose modulates L-type Ca²⁺ channel activity and vascular reactivity are unclear. Here the authors report a nanocomplex orchestrated by AKAP5 that facilitates local purinergic stimulation of L-type Ca²⁺ channels and vasoconstriction during diabetic hyperglycemia.