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Abstract Expansion microscopy, whereby the relative positions of biomolecules are physically increased via hydrogel expansion, can be used to reveal ultrafine structures of cells under a conventional microscope. Despite its utility for achieving super-resolution imaging, expansion microscopy suffers a major drawback, namely reduced fluorescence signals caused by excessive proteolysis and swelling effects. This caveat results in a lower photon budget and disfavors fluorescence imaging over a large field of view that can cover an entire expanded cell, especially in 3D. In addition, the complex procedures and specialized reagents of expansion microscopy hinder its popularization. Here, we modify expansion microscopy by deploying trypsin digestion to reduce protein loss and tyramide signal amplification to enhance fluorescence signal for point-scanning-based imaging. We name our new methodology TT-ExM to indicate dual trypsin and tyramide treatments. TT-ExM may be applied for both antibody and lipid staining. TT-ExM displayed enhanced protein retention for endoplasmic reticulum and mitochondrial markers in COS-7 cell cultures. Importantly, TT-ExM-based lipid staining clearly revealed the complex 3D membrane structures in entire expanded cells. Through combined lipid and DNA staining, our TT-ExM methodology highlighted mitochondria by revealing their DNA and membrane structures in cytoplasm, as well as the lipid-rich structures formed via phase separation in nuclei at interphase. We also observed lipid-rich chromosome matrices in the mitotic cells. These high-quality 3D images demonstrate the practicality of TT-ExM. Thus, readily available reagents can be deployed in TT-ExM to significantly enhance fluorescence signals and generate high-quality and ultrafine-resolution images under confocal microscopy.

Serine(S)/threonine(T)-glutamine(Q) cluster domains (SCDs), polyglutamine (polyQ) tracts and polyglutamine/asparagine (polyQ/N) tracts are Q-rich motifs found in many proteins. SCDs often are intrinsically disordered regions that mediate protein phosphorylation and protein-protein interactions. PolyQ and polyQ/N tracts are structurally flexible sequences that trigger protein aggregation. We report that due to their high percentages of STQ or STQN amino acid content, four SCDs and three prion-causing Q/N-rich motifs of yeast proteins possess autonomous protein expression-enhancing activities. Since these Q-rich motifs can endow proteins with structural and functional plasticity, we suggest that they represent useful toolkits for evolutionary novelty. Comparative Gene Ontology (GO) analyses of the near-complete proteomes of 26 representative model eukaryotes reveal that Q-rich motifs prevail in proteins involved in specialized biological processes, including Saccharomyces cerevisiae RNA-mediated transposition and pseudohyphal growth, Candida albicans filamentous growth, ciliate peptidyl-glutamic acid modification and microtubule-based movement, Tetrahymena thermophila xylan catabolism and meiosis, Dictyostelium discoideum development and sexual cycles, Plasmodium falciparum infection, and the nervous systems of Drosophila melanogaster, Mus musculus and Homo sapiens. We also show that Q-rich-motif proteins are expanded massively in 10 ciliates with reassigned TAAQ and TAGQ codons. Notably, the usage frequency of CAGQ is much lower in ciliates with reassigned TAAQ and TAGQ codons than in organisms with expanded and unstable Q runs (e.g. D. melanogaster and H. sapiens), indicating that the use of noncanonical stop codons in ciliates may have coevolved with codon usage biases to avoid triplet repeat disorders mediated by CAG/GTC replication slippage.

Dendritic spines, the tiny and actin-rich protrusions emerging from dendrites, are the subcellular locations of excitatory synapses in the mammalian brain that control synaptic activity and plasticity. Dendritic spines contain a specialized form of endoplasmic reticulum (ER), i.e., the spine apparatus, required for local calcium signaling and that is involved in regulating dendritic spine enlargement and synaptic plasticity. Many autism-linked genes have been shown to play critical roles in synaptic formation and plasticity. Among them, KLHL17 is known to control dendritic spine enlargement during development. As a brain-specific disease-associated gene, KLHL17 is expected to play a critical role in the brain, but it has not yet been well characterized. In this study, we report that KLHL17 expression in mice is strongly regulated by neuronal activity and KLHL17 modulates the synaptic distribution of synaptopodin (SYNPO), a marker of the spine apparatus. Both KLHL17 and SYNPO are F-actin-binding proteins linked to autism. SYNPO is known to maintain the structure of the spine apparatus in mature spines and contributes to synaptic plasticity. Our super-resolution imaging using expansion microscopy demonstrates that SYNPO is indeed embedded into the ER network of dendritic spines and that KLHL17 is closely adjacent to the ER/SYNPO complex. Using mouse genetic models, we further show that Klhl17 haploinsufficiency and knockout result in fewer dendritic spines containing ER clusters and an alteration of calcium events at dendritic spines. Accordingly, activity-dependent dendritic spine enlargement and neuronal activation (reflected by extracellular signal-regulated kinase (ERK) phosphorylation and C-FOS expression) are impaired. In addition, we show that the effect of disrupting the KLHL17 and SYNPO association is similar to the results of Klhl17 haploinsufficiency and knockout, further strengthening the evidence that KLHL17 and SYNPO act together to regulate synaptic plasticity. In conclusion, our findings unravel a role for KLHL17 in controlling synaptic plasticity via its regulation of SYNPO and synaptic ER clustering and imply that impaired synaptic plasticity contributes to the etiology of KLHL17-related disorders.

Autism impacts synapses. This study reports that autism-linked mutations of CTTNBP2 regulate phase separation to control synaptic enrichment of that protein. A zinc-induced liquid-to-gel transition improves synaptic retention of CTTNBP2 and SHANK3.

Osteosarcoma is a malignant tumor abundant in vascular tissue, and its rich blood supply may have a significant impact on its metabolic characteristics. PDGFR[beta] is a membrane receptor highly expressed in osteosarcoma cells and vascular wall cells, and its effect on osteosarcoma metabolism needs to be further studied. In this study, we discussed the effect and mechanism of action of PDGFR[beta] on glucose metabolism in human osteosarcoma (HOS) cells. GSEA, Pearson's correlation test, and PPI correlation analysis indicated positive regulation of PDGFR[beta] on aerobic glycolysis in osteosarcoma. The results of qPCR and western blot further confirmed the prediction of bioinformatics. Glucose metabolism experiments proved that PDGF/PDGFR[beta] could effectively promote aerobic glycolysis in osteosarcoma cells. In addition, the mitochondrial membrane potential ([DELTA][PSI]m) experiment proved that the metabolic change triggered by PDGFR[beta] was not caused by mitochondrial damage. The PI3K pathway inhibitor LY294002, MEK pathway inhibitor U0126, or Warburg effect inhibitor DCA was used to perform western blot and glucose metabolism experiments, and the results showed that PDGFBB/PDGFR[beta] mainly activated the PI3K/AKT/mTOR/c-Myc pathway to promote aerobic glycolysis in osteosarcoma HOS cells. The newly elucidated role of PDGFR[beta] provides a novel metabolic therapeutic target for osteosarcoma. Key words: PDGFR[beta], metabolic reprogramming, aerobic glycolysis, osteosarcoma, c-Myc. L'osteosarcome est une tumeur maligne riche en tissu vasculaire, et son approvisionnement eleve en sang peut avoir un impact significatif sur ses caracteristiques metaboliques. Le PDGFR[beta] est un recepteur membranaire fortement exprime dans les cellules d'osteosarcome et les cellules de la paroi vasculaire, et son effet sur le metabolisme de l'osteosarcome doit etre etudie plus en detail. Dans cette etude, les auteurs ont discute de l'effet et du mecanisme du PDGFR[beta] sur le metabolisme du glucose des cellules d'osteosarcome HOS. Tout d'abord, l'analyse d'enrichissement genique GSEA, le test de correlation de Pearson et l'analyse de correlation des interactions proteine-proteine ont indique une regulation positive du PDGFR[beta] sur la glycolyse aerobie dans l'osteosarcome. Les resultats de la qPCR et du transfert de Western ont egalement confirme la prediction de la bio-informatique. Les experiences sur le metabolisme du glucose ont prouve que le PDGF/PDGFR[beta] pouvait efficacement promouvoir la glycolyse aerobie dans les cellules d'osteosarcome. En outre, l'experience realisee sur le potentiel de la mem-brane mitochondriale a demontre que le changement metabolique declenche par le PDGFR[beta] n'etait pas provoque par des dom-mages mitochondriaux. Le LY294002, un inhibiteur de la voie PI3K, le U0126, un inhibiteur de la voie MEK, ou le DCA, un inhibiteur de l'effet Warburg, ont ete utilises pour realiser des experiences en transfert de Western et sur le metabolisme du glucose, et les resultats ont montre que le PDGFBB/PDGFR[beta] activait principalement la voie PI3K/AKT/mTOR/c-Myc pour promouvoir la glycolyse aerobie dans les cellules d'osteosarcome HOS. Le role nouvellement elucide du PDGFR[beta] fournit une nouvelle cible therapeutique metabolique pour l'osteosarcome. [Traduit par la Redaction] Mots-cles: PDGFR[beta], reprogrammation metabolique, glycolyse aerobie, osteosarcome, c-Myc., 1. Introduction Osteosarcoma is a malignant bone tumor with abundant blood vessels, and the instability of its neovascularization may lead to a change in the oxygenation state of the tumor [...]

The southwestern Tianshan Mountains is an important producing area of the Meso-Cenozoic stratabound glutenite-type Cu-Pb-Zn deposits in Xinjiang. Sareke copper mine, Wulagen lead-zinc mine, Huayuan copper mine and Jiashi copper mine are the representative deposits, which all occur in the red bed basin on the edge of the uplift denudation area and are strictly controlled by strata. The lower part of the ore-bearing basin is composed of coal-bearing hydrocarbon-generating rocks, the middle part is well-permeable glutenites as the Cu-Pb-Zn reservoir, and the overlying layer is a sealed cap formed by gypsum rocks and mudstones, showing the ore-forming characteristics of co-enrichment of Cu-Pb-Zn-Uranium-coal-natural gas in the same basin. In this paper, we summarized the sedimentary-tectonic evolution of these ore-bearing basins and the characteristics of ore-bearing layers, and analyzed the ore-controlling conditions and metallogenic characteristics of typical copper, lead and zinc deposits. Combining with comparative analysis, we summarized the regional metallogenic regularity of the Meso-Cenozoic glutenite-type Cu-Pb-Zn deposit, and hold the view that organic matter is closely related to Cu-Pb-Zn mineralization. Moreover, it is inferred that Cu-Pb-Zn-lean ore bodies were formed over the original source layer in the uplift caused by the superimposition of oilfield brine; Cu-Pb-Zn-rich ore bodies were formed by the superimposition of deep-source ore-forming fluids from the Himalayan fault structure. The metallogenic model of the middle Cenozoic stratabound glutenite-type Cu-Pb-Zn deposits in the southwestern Tianshan Mountains provides a basis for the exploration of the known mines in their deep and edge, and also provides guidance for the regional prospecting work.

Lithium-ion batteries, as the main energy storage component of electric vehicles (EVs), play a crucial role in ensuring the safe and reliable operation of the battery systems through monitoring their state of health (SOH). However, temperature variations and battery aging have significant impacts on the internal parameters of lithium-ion batteries, and these changes directly correlate with the accuracy of battery SOH estimation. To address these issues, this paper proposes an estimation method for lithium-ion battery SOH that considers the impact of temperature. The method begins with reconstructing a second-order hybrid equivalent circuit model for lithium-ion batteries, through which an adaptive update rate for battery model parameters is designed. On this basis, a nonlinear observer for battery states is introduced by integrating filters to estimate SOH. The proposed method considers the impact of capacity in the design of the parameter adaptive update rate, enabling the capacity to be dynamically adjusted based on the actual state of the batteries. This reduces the cumulative error in the SOC observer and improves the modeling accuracy of battery models. Experimental results demonstrate that the method proposed in this paper exhibits exceptional performance in SOH estimation under different temperature conditions. The mean absolute error for SOH estimation does not exceed 0.5%, and the root mean square error does not exceed 0.2%. This method can significantly improve the estimation accuracy of SOH, providing a more efficient and accurate solution for battery management systems in EVs. [ABSTRACT FROM AUTHOR]

Solids in nature can be generally classified into crystalline and non-crystalline states.sup.1-7, depending on whether long-range lattice periodicity is present in the material. The differentiation of the two states, however, could face fundamental challenges if the degree of long-range order in crystals is significantly reduced. Here we report a paracrystalline state of diamond that is distinct from either crystalline or amorphous diamond.sup.8-10. The paracrystalline diamond reported in this work, consisting of sub-nanometre-sized paracrystallites that possess a well-defined crystalline medium-range order up to a few atomic shells.sup.4,5,11-13, was synthesized in high-pressure high-temperature conditions (for example, 30 GPa and 1,600 K) employing face-centred cubic C.sub.60 as a precursor. The structural characteristics of the paracrystalline diamond were identified through a combination of X-ray diffraction, high-resolution transmission microscopy and advanced molecular dynamics simulation. The formation of paracrystalline diamond is a result of densely distributed nucleation sites developed in compressed C.sub.60 as well as pronounced second-nearest-neighbour short-range order in amorphous diamond due to strong sp.sup.3 bonding. The discovery of paracrystalline diamond adds an unusual diamond form to the enriched carbon family.sup.14-16, which exhibits distinguishing physical properties and can be furthered exploited to develop new materials. Furthermore, this work reveals the missing link in the length scale between amorphous and crystalline states across the structural landscape, having profound implications for recognizing complex structures arising from amorphous materials. A study describes the synthesis, structural characterization and formation mechanism of a paracrystalline state of diamond, adding an unusual form of diamond to the family of carbon-based materials., Author(s): Hu Tang [sup.1] , Xiaohong Yuan [sup.1] , Yong Cheng [sup.2] , Hongzhan Fei [sup.3] , Fuyang Liu [sup.1] , Tao Liang [sup.1] , Zhidan Zeng [sup.1] , Takayuki [...]