Illuminating G-Protein-Coupling Selectivity of GPCRs.

Heterotrimetic G proteins consist of four subfamilies (Gs, Gi/o, Gq/11, and G12/13) that mediate signaling via G-protein-coupled receptors (GPCRs), principally by receptors binding Gα C termini. G-protein-coupling profiles govern GPCR-induced cellular responses, yet receptor sequence selectivity determinants remain elusive. Here, we systematically quantified ligand-induced interactions between 148 GPCRs and all 11 unique Gα subunit C termini. For each receptor, we probed chimeric Gα subunit activation via a transforming growth factor-α (TGF-α) shedding response in HEK293 cells lacking endogenous Gq/11 and G12/13 proteins, and complemented G-protein-coupling profiles through a NanoBiT-G-protein dissociation assay. Interrogation of the dataset identified sequence-based coupling specificity features, inside and outside the transmembrane domain, which we used to develop a coupling predictor that outperforms previous methods. We used the predictor to engineer designer GPCRs selectively coupled to G12. This dataset of fine-tuned signaling mechanisms for diverse GPCRs is a valuable resource for research in GPCR signaling.

Heterotrimeric G Protein Subunit Gαq Is a Master Switch for Gßγ-Mediated Calcium Mobilization by Gi-Coupled GPCRs.

Mechanisms that control mobilization of cytosolic calcium [Ca2+]i are key for regulation of numerous eukaryotic cell functions. One such paradigmatic mechanism involves activation of phospholipase Cß (PLCß) enzymes by G protein ßγ subunits from activated Gαi-Gßγ heterotrimers. Here, we report identification of a master switch to enable this control for PLCß enzymes in living cells. We find that the Gαi-Gßγ-PLCß-Ca2+ signaling module is entirely dependent on the presence of active Gαq. If Gαq is pharmacologically inhibited or genetically ablated, Gßγ can bind to PLCß but does not elicit Ca2+ signals. Removal of an auto-inhibitory linker that occludes the active site of the enzyme is required and sufficient to empower "stand-alone control" of PLCß by Gßγ. This dependence of Gi-Gßγ-Ca2+ on Gαq places an entire signaling branch of G-protein-coupled receptors (GPCRs) under hierarchical control of Gq and changes our understanding of how Gi-GPCRs trigger [Ca2+]i via PLCß enzymes.

A tale of two copies: Evolutionary trajectories of moth pheromone receptors.

Pheromone communication is an essential component of reproductive isolation in animals. As such, evolution of pheromone signaling can be linked to speciation. For example, the evolution of sex pheromones is thought to have played a major role in the diversification of moths. In the crop pests Spodoptera littoralis and S. litura, the major component of the sex pheromone blend is (Z,E)-9,11-tetradecadienyl acetate, which is lacking in other Spodoptera species. It indicates that a major shift occurred in their common ancestor. It has been shown recently in S. littoralis that this compound is detected with high specificity by an atypical pheromone receptor, named SlitOR5. Here, we studied its evolutionary history through functional characterization of receptors from different Spodoptera species. SlitOR5 orthologs in S. exigua and S. frugiperda exhibited a broad tuning to several pheromone compounds. We evidenced a duplication of OR5 in a common ancestor of S. littoralis and S. litura and found that in these two species, one duplicate is also broadly tuned while the other is specific to (Z,E)-9,11-tetradecadienyl acetate. By using ancestral gene resurrection, we confirmed that this narrow tuning evolved only in one of the two copies issued from the OR5 duplication. Finally, we identified eight amino acid positions in the binding pocket of these receptors whose evolution has been responsible for narrowing the response spectrum to a single ligand. The evolution of OR5 is a clear case of subfunctionalization that could have had a determinant impact in the speciation process in Spodoptera species.

Conformational transitions of a neurotensin receptor 1-Gi1 complex.

Neurotensin receptor 1 (NTSR1) is a G-protein-coupled receptor (GPCR) that engages multiple subtypes of G protein, and is involved in the regulation of blood pressure, body temperature, weight and the response to pain. Here we present structures of human NTSR1 in complex with the agonist JMV449 and the heterotrimeric Gi1 protein, at a resolution of 3 Å. We identify two conformations: a canonical-state complex that is similar to recently reported GPCR-Gi/o complexes (in which the nucleotide-binding pocket adopts more flexible conformations that may facilitate nucleotide exchange), and a non-canonical state in which the G protein is rotated by about 45 degrees relative to the receptor and exhibits a more rigid nucleotide-binding pocket. In the non-canonical state, NTSR1 exhibits features of both active and inactive conformations, which suggests that the structure may represent an intermediate form along the activation pathway of G proteins. This structural information, complemented by molecular dynamics simulations and functional studies, provides insights into the complex process of G-protein activation.

Liquid Metal Doping Induced Asymmetry in Two-Dimensional Metal Oxides.

The emergence of ferroelectricity in two-dimensional (2D) metal oxides is a topic of significant technological interest; however, many 2D metal oxides lack intrinsic ferroelectric properties. Therefore, introducing asymmetry provides access to a broader range of 2D materials within the ferroelectric family. Here, the generation of asymmetry in 2D SnO by doping the material with Hf0.5Zr0.5O2 (HZO) is demonstrated. A liquid metal process as a doping strategy for the preparation of 2D HZO-doped SnO with robust ferroelectric characteristics is implemented. This technology takes advantage of the selective interface enrichment of molten Sn with HZO crystallites. Molecular dynamics simulations indicate a strong tendency of Hf and Zr atoms to migrate toward the surface of liquid metal and embed themselves within the growing oxide layer in the form of HZO. Thus, the liquid metal-based harvesting/doping technique is a feasible approach devised for producing novel 2D metal oxides with induced ferroelectric properties, represents a significant development for the prospects of random-access memories.

Potential and performance of anisotropic 19F NMR for the enantiomeric analysis of fluorinated chiral active pharmaceutical ingredients.

Controlling the enantiomeric purity of chiral drugs is of paramount importance in pharmaceutical chemistry. Isotropic 1H NMR spectroscopy involving chiral agents is a widely used method for discriminating enantiomers and quantifying their relative proportions. However, the relatively weak spectral separation of enantiomers (1H Δδiso(R, S)) in frequency units at low and moderate magnetic fields, as well as the lack of versatility of a majority of those agents with respect to different chemical functions, may limit the general use of this approach. In this article, we investigate the analytical potential of 19F NMR in anisotropic chiral media for the enantiomeric analysis of fluorinated active pharmaceutical ingredients (API) via two residual anisotropic NMR interactions: the chemical shift anisotropy (19F-RCSA) and dipolar coupling ((19F-19F)-RDC). Lyotropic chiral liquid crystals (CLC) based on poly-γ-benzyl-L-glutamate (PBLG) show an interesting versatility and adaptability to enantiodiscrimination as illustrated for two chiral drugs, Flurbiprofen® (FLU) and Efavirenz® (EFA), which have very different chemical functions. The approach has been tested on a routine 300 MHz NMR spectrometer equipped with a standard probe (5 mm BBFO probe) in a high-throughput context (i.e., ≈10 s of NMR experiments) while the performance for enantiomeric excess (ee) measurement is evaluated in terms of trueness and precision. The limits of detection (LOD) determined were 0.17 and 0.16 µmol ml-1 for FLU and EFA, respectively, allow working in dilute conditions even with such a short experimental duration. The enantiodiscrimination capabilities are also discussed with respect to experimental features such as CLC composition and temperature.

A Gradient-Descent Optimization of CO2-CO-NOx Emissions over the Paris Megacity─The Case of the First SARS-CoV-2 Lockdown.

Urban greenhouse gas emissions monitoring is essential to assessing the impact of climate mitigation actions. Using atmospheric continuous measurements of air quality and carbon dioxide (CO2), we developed a gradient-descent optimization system to estimate emissions of the city of Paris. We evaluated our joint CO2-CO-NOx optimization over the first SARS-CoV-2 related lockdown period, resulting in a decrease in emissions by 40% for NOx and 30% for CO2, in agreement with preliminary estimates using bottom-up activity data yet lower than the decrease estimates from Bayesian atmospheric inversions (50%). Before evaluating the model, we first provide an in-depth analysis of three emission data sets. A general agreement in the totals is observed over the region surrounding Paris (known as Île-de-France) since all the data sets are constrained by the reported national and regional totals. However, the data sets show disagreements in their sector distributions as well as in the interspecies ratios. The seasonality also shows disagreements among emission products related to nonindustrial stationary combustion (residential and tertiary combustion). The results presented in this paper show that a multispecies approach has the potential to provide sectoral information to monitor CO2 emissions over urban areas enabled by the deployment of collocated atmospheric greenhouse gases and air quality monitoring stations.

Altered Sweat Composition Due to Changes in Tight Junction Expression of Sweat Glands in Cholinergic Urticaria Patients.

In cholinergic urticaria (CholU), small, itchy wheals are induced by exercise or passive warming and reduced sweating has been reported. Despite the described reduced muscarinic receptor expression, sweat duct obstruction, or sweat allergy, the underlying pathomechanisms are not well understood. To gain further insights, we collected skin biopsies before and after pulse-controlled ergometry and sweat after sauna provocation from CholU patients as well as healthy controls. CholU patients displayed partially severely reduced local sweating, yet total sweat volume was unaltered. However, sweat electrolyte composition was altered, with increased K+ concentration in CholU patients. Formalin-fixed, paraffin-embedded biopsies were stained to explore sweat leakage and tight junction protein expression. Dermcidin staining was not found outside the sweat glands. In the secretory coils of sweat glands, the distribution of claudin-3 and -10b as well as occludin was altered, but the zonula occludens-1 location was unchanged. In all, dermcidin and tight junction protein staining suggests an intact barrier with reduced sweat production capability in CholU patients. For future studies, an ex vivo skin model for quantification of sweat secretion was established, in which sweat secretion could be pharmacologically stimulated or blocked. This ex vivo model will be used to further investigate sweat gland function in CholU patients and decipher the underlying pathomechanism(s).

Mechanistic Observation of Interactions between Macrophages and Inorganic Particles with Different Densities.

Many different types of inorganic materials are processed into nano/microparticles for medical utilization. The impact of selected key characteristics of these particles, including size, shape, and surface chemistries, on biological systems, is frequently studied in clinical contexts. However, one of the most important basic characteristics of these particles, their density, is yet to be investigated. When the particles are designed for drug delivery, highly mobile macrophages are the major participants in cellular levels that process them in vivo. As such, it is essential to understand the impact of particles' densities on the mobility of macrophages. Here, inorganic particles with different densities are applied, and their interactions with macrophages studied. A set of these particles are incubated with the macrophages and the outcomes are explored by optical microscopy. This microscopic view provides the understanding of the mechanistic interactions between particles of different densities and macrophages to conclude that the particles' density can affect the migratory behaviors of macrophages: the higher the density of particles engulfed inside the macrophages, the less mobile the macrophages become. This work is a strong reminder that the density of particles cannot be neglected when they are designed to be utilized in biological applications.

Performance Analysis of a Repetition Cat Code Architecture: Computing 256-bit Elliptic Curve Logarithm in 9 Hours with 126 133 Cat Qubits.

Cat qubits provide appealing building blocks for quantum computing. They exhibit a tunable noise bias yielding an exponential suppression of bit flips with the average photon number and a protection against the remaining phase errors can be ensured by a simple repetition code. We here quantify the cost of a repetition code and provide valuable guidance for the choice of a large scale architecture using cat qubits by realizing a performance analysis based on the computation of discrete logarithms on an elliptic curve with Shor's algorithm. By focusing on a 2D grid of cat qubits with neighboring connectivity, we propose to implement 2-qubit gates via lattice surgery and Toffoli gates with off-line fault-tolerant preparation of magic states through projective measurements and subsequent gate teleportations. All-to-all connectivity between logical qubits is ensured by routing qubits. Assuming a ratio between single- and two-photon losses of 10^{-5} and a cycle time of 500 ns, we show concretely that such an architecture can compute a 256-bit elliptic curve logarithm in 9 h with 126 133 cat qubits and on average 19 photons by cat state. We give the details of the realization of Shor's algorithm so that the proposed performance analysis can be easily reused to guide the choice of architecture for others platforms.

Anisotropic 1 H STD-NMR Spectroscopy: Exploration of Enantiomer-Polypeptide Interactions in Chiral Oriented Environments.

The front cover artwork is provided by Dr. Philippe Lesot's group (NMR in Oriented Media, ICMMO, UMR CNRS 8182) at Université Paris-Saclay, France. The image shows four pieces of a puzzle: the magnet of an NMR spectrometer, the principle of the 1 H STD-NMR experiment and the 3D helical structure of the poly-γ-benzyl-L-glutamate polymer leading to a chiral liquid-crystalline phase that discriminates the enantiomers of a model chiral solute (1-phenethyl alcohol). Putting these pieces of the puzzle together allows us to identify the hydrogen sites of each enantiomer interacting with the polypeptide side chain. These new outcomes are a further step towards a global understanding of the chiral recognition that occurs in such media. Read the full text of the Research Article at 10.1002/cphc.202200508.

Anisotropic 1 H STD-NMR Spectroscopy: Exploration of Enantiomer-Polypeptide Interactions in Chiral Oriented Environments.

We explore and report for the first time the use of 1 H saturation transfer difference NMR experiments (STD-NMR) in weakly aligning chiral anisotropic media to identify the hydrogen sites of enantiomers of small chiral molecules interacting with the side-chain of poly-γ-benzyl-l-glutamate (PBLG), a helically chiral polypeptide polymer. The first experimental results obtained on three model mono-stereogenic compounds outcomes are highly promising and demonstrate the possibility to track down possible differences of spatial position of enantiomers at the vicinity of the polymer side-chain. Anisotropic STD experiments appear to be well suited for rapid screening of chiral analytes that bind favorably to orienting polymeric systems, while providing new insights into the mechanism of enantio-discrimination without resorting to the time-consuming determination of molecular order parameters.

Identification of the optimal medical and surgical management for patients with perianal fistulising Crohn's disease.

AIM: The aim of our study was to assess the best medical and surgical approaches for perianal Crohn's disease (PCD) in order to identify an optimal combined medical and surgical treatment. METHODS: Medical records of all patients with PCD treated with TNFα antagonists in two referral centres between 1998 and 2018 were reviewed. Predictors of long-term outcomes were identified using a Cox proportional hazard model. RESULTS: A total of 200 patients were included. Fifty-three patients (26.5%) were treated with adalimumab and 147 (73.5%) with infliximab. A combination of TNFα antagonist with an immunosuppressant and the presence of proctitis were independently associated with fistula closure. Seton was placed in 127 patients (63.5%) before starting biological therapy. Eighty patients (40%) underwent additional perineal surgery. Prior PCD surgery, seton positioning, additional perineal surgery, and additional surgery within 52 weeks of anti-TNFα treatment were associated with an increased rate of fistula closure. Finally, medical combination therapy (anti-TNFα plus immunosuppressant) along with seton placement and additional surgery within 1 year was the best management for PCD patients (p = 0.02). CONCLUSION: Combined medical and surgical management is required for the treatment of PCD patients. Medical combination therapy associated with seton placement and additional surgery within 1 year is the best management for PCD patients.

Synthesis and In Situ Behavior of 1,4- and 2,5-(13C) Isotopomers of p-Phenylenediamine in Reconstructed Human Epidermis Using High Resolution Magic Angle Spinning NMR.

p-Phenylenediamine (PPD) has been classified as a strong skin allergen, but when it comes to toxicological concerns, benzoquinone diamine (BQDI), the primary oxidation derivative of PPD, is frequently considered and was shown to covalently bind nucleophilic residues on model peptides. However, tests in solution are far from providing a reliable model, as the cutaneous metabolism of PPD is not covered. We now report the synthesis of two 13C substituted isotopomers of PPD, 1,4-(13C)p-phenylenediamine 1 and 2,5-(13C)p-phenylenediamine 2, and the investigation of their reactivity in reconstructed human epidermis (RHE) using the high resolution magic angle spinning (HRMAS) NMR technique. RHE samples were first treated with 1 or 2 and incubated for 1 to 48 h. Compared to the control, spectra clearly showed only the signals of 1 or 2 gradually decreasing with time to disappear after 48 h of incubation. However, the culture media of RHE incubated with 1 for 1 and 24 h, respectively, showed the presence of both monoacetylated- and diacetylated-PPD as major products. Therefore, the acetylation reaction catalyzed by N-acetyltransferase (NAT) enzymes appeared to be the main process taking place in RHE. With the aim of increasing the reactivity by oxidation, 1 and 2 were treated with 0.5 equiv of H2O2 prior to their application to RHE and incubated for different times. Under these conditions, new peaks having close chemical shifts to those of PPD-cysteine adducts previously observed in solution were detected. Under such oxidative conditions, we were thus able to detect and quantify cysteine adducts in RHE (maximum of 0.2 nmol/mg of RHE at 8 h of incubation) while no reaction with other nucleophilic amino acid residues could be observed.

PIAS2-mediated blockade of IFN-ß signaling: a basis for sporadic Parkinson disease dementia.

Familial Parkinson disease (PD) is associated with rare genetic mutations, but the etiology in most patients with sporadic (s)PD is largely unknown, and the basis for its progression to dementia (sPDD) is poorly characterized. We have identified that loss of IFNß or IFNAR1, the receptor for IFNα/ß, causes pathological and behavioral changes resembling PDD, prompting us to hypothesize that dysregulated genes in IFNß-IFNAR signaling pathway predispose one to sPD. By transcriptomic analysis, we found defective neuronal IFNß-IFNAR signaling, including particularly elevated PIAS2 associated with sPDD. With meta-analysis of GWASs, we identified sequence variants in IFNß-IFNAR-related genes in sPD patients. Furthermore, sPDD patients expressed higher levels of PIAS2 mRNA and protein in neurons. To determine its function in brain, we overexpressed PIAS2 under a neuronal promoter, alone or with human α-synuclein, in the brains of mice, which caused motor and cognitive impairments and correlated with intraneuronal phosphorylated (p)α-synuclein accumulation and dopaminergic neuron loss. Ectopic expression of neuronal PIAS2 blocked mitophagy, increased the accumulation of senescent mitochondrial and oxidative stress, as evidenced by excessive oxDJ1 and 8OHdG, by inactivating ERK1/2-P53 signaling. Conversely, PIAS2 knockdown rescued the clinicopathological manifestations of PDD in Ifnb-/- mice on restoring mitochondrial homeostasis, oxidative stress, and pERK1/2-pP53 signaling. The regulation of JAK-STAT2-PIAS2 signaling was crucial for neurite outgrowth and neuronal survival and excitability and thus might prevent cognitive impairments. Our findings provide insights into the progression of sPD and dementia and have implications for new therapeutic approaches.

Stability of enveloped and nonenveloped viruses in hydrolyzed gelatin liquid formulation.

BACKGROUND: The thermal stability of viruses in gelatin liquid formulations for medical research and application is poorly understood and this study aimed to examine the thermal stability of 4 enveloped and nonenveloped DNA and RNA viruses in hydrolyzed gelatin liquid formulations. METHODS: Bovine herpesvirus (BHV) was used as a model virus to examine the molecular weight (MW), concentration and gelatin type and to optimize virus stability in liquid formulations at 25 °C and 4 °C. Using the model virus liquid formulation, the stability of multiple enveloped and nonenveloped RNA and DNA viruses, including parainfluenza virus, reovirus (RV), BHV, and adenovirus (AdV), was monitored over up to a 30-week storage period. RESULTS: The BHV model virus was considered stable after 3 weeks in hydrolyzed gelatin (MW: 4000) with a 0.8 LRV (log10 reduction value) at 25 °C or a 0.2 LRV at 4 °C, compared to the stabilities observed in higher MW gelatin (60,000 and 160,000) with an LRV above 1. Based on the gelatin type, BHV in alkaline-treated hydrolyzed gelatin samples were unexpectantly more stable than in acid-treated hydrolyzed gelatin sample. All four viruses exhibited stability at 4 °C for at least 8 weeks, BHV or AdV remained stable for over 30 weeks of storage, and at 25 °C, AdV and RV remained stable for 8 weeks. CONCLUSION: The results demonstrated that 5% of 4000 MW hydrolyzed gelatin formulation can act as a relevant stabilizer for the thermal stability of viruses in medical research and application.

Assessing the Effectiveness of an Urban CO2 Monitoring Network over the Paris Region through the COVID-19 Lockdown Natural Experiment.

The Paris metropolitan area, the largest urban region in the European Union, has experienced two national COVID-19 confinements in 2020 with different levels of restrictions on mobility and economic activity, which caused reductions in CO2 emissions. To quantify the timing and magnitude of daily emission reductions during the two lockdowns, we used continuous atmospheric CO2 monitoring, a new high-resolution near-real-time emission inventory, and an atmospheric Bayesian inverse model. The atmospheric inversion estimated the changes in fossil fuel CO2 emissions over the Greater Paris region during the two lockdowns, in comparison with the same periods in 2018 and 2019. It shows decreases by 42-53% during the first lockdown with stringent measures and by only 20% during the second lockdown when traffic reduction was weaker. Both lockdown emission reductions are mainly due to decreases in traffic. These results are consistent with independent estimates based on activity data made by the city environmental agency. We also show that unusual persistent anticyclonic weather patterns with north-easterly winds that prevailed at the start of the first lockdown period contributed a substantial drop in measured CO2 concentration enhancements over Paris, superimposed on the reduction of urban CO2 emissions. We conclude that atmospheric CO2 monitoring makes it possible to identify significant emission changes (>20%) at subannual time scales over an urban region.

Rethinking the Approach to Preclinical Models of Anorexia Nervosa.

PURPOSE OF REVIEW: The goal of this review is to describe how emerging technological developments in pre-clinical animal research can be harnessed to accelerate research in anorexia nervosa (AN). RECENT FINDINGS: The activity-based anorexia (ABA) paradigm, the best characterized animal model of AN, combines restricted feeding, excessive exercise, and weight loss. A growing body of evidence supports the idea that pathophysiological weight loss in this model is due to cognitive inflexibility, a clinical feature of AN. Targeted manipulations that recapitulate brain changes reported in AN - hyperdopaminergia or hyperactivity of cortical inputs to the nucleus accumbens - exacerbate weight loss in the ABA paradigm, providing the first evidence of causality. The power of preclinical research lies in the ability to assess the consequences of targeted manipulations of neuronal circuits that have been implicated in clinical research. Additional paradigms are needed to capture other features of AN that are not seen in ABA.

A Wireless Autonomous Real-Time Underwater Acoustic Positioning System.

Recent acoustic telemetry positioning systems are able to reconstruct the positions and trajectories of organisms at a scale of a few centimeters to a few meters. However, they present several logistical constraints including receiver maintenance, calibration procedures and limited access to real-time data. We present here a novel, easy-to-deploy, energy self-sufficient underwater positioning system based on the time difference of arrival (TDOA) algorithm and the Global System for Mobile (GSM) communication technology, capable of locating tagged marine organisms in real time. We provide an illustration of the application of this system with empirical examples using continuous and coded tags in fish and benthic invertebrates. In situ experimental tests of the operational system demonstrated similar performances to currently available acoustic positioning systems, with a global positioning error of 7.13 ± 5.80 m (mean ± SD) and one-third of the pings can be localized within 278 m of the farthest buoy. Despite some required improvements, this prototype is designed to be autonomous and can be deployed from the surface in various environments (rivers, lakes, and oceans). It was proven to be useful to monitor a wide variety of species (benthic and pelagic) in real time. Its real-time property can be used to rapidly detect system failure, optimize deployment design, or for ecological or conservation applications.

Bi-Sn Catalytic Foam Governed by Nanometallurgy of Liquid Metals.

Metallic foams, with intrinsic catalytic properties, are critical for heterogeneous catalysis reactions and reactor designs. Market ready catalytic foams are costly and made of multimaterial coatings with large sub-millimeter open cells providing insufficient active surface area. Here we use the principle of nanometallurgy within liquid metals to prepare nanostructured catalytic metal foams using a low-cost alloy of bismuth and tin with sub-micrometer open cells. The eutectic bismuth and tin liquid metal alloy was processed into nanoparticles and blown into a tin and bismuth nanophase separated heterostructure in aqueous media at room temperature and using an indium brazing agent. The CO2 electroconversion efficiency of the catalytic foam is presented with an impressive 82% conversion efficiency toward formates at high current density of -25 mA cm-2 (-1.2 V vs RHE). Nanometallurgical process applied to liquid metals will lead to exciting possibilities for expanding industrial and research accessibility of catalytic foams.