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Objective. The purpose of the present study was to explore the biomarkers related to lung cancer based on the bioinformatics method, which might be new targets for lung cancer treatment. Methods. GSE17681 and GSE18842 were obtained from the Gene Expression Omnibus (GEO) database. The differentially expressed miRNAs (DEMs) and genes (DEGs) in lung cancer samples were screened via the GEO2R online tool. DEMs were submitted to the mirDIP website to predict target genes. Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis were conducted via uploading DEGs to the DAVID database. The protein-protein interaction network (PPI) of the DEGs was analyzed by STRING’s online tool. Then, the PPI network was visualized using Cytoscape 3.8.0. Results. 46 DEMs were identified in GSE17681, and the website predicted that there were 873 target genes of these DEMs. 1029 DEGs were identified in the GSE18842 chip. GO analysis suggested that the co-DEGs participated in the canonical Wnt signaling pathway, regulation of the Wnt signaling pathway, a serine/threonine kinase signaling pathway, the Wnt signaling pathway, and cell-cell signaling by Wnt. KEGG analysis results showed the co-DEGs of GSE17681 and GSE18842 were related to the Hippo signaling pathway and adhesion molecules. In addition, six hub genes that were related to lung cancer were identified as hub genes, including mTOR, NF1, CHD7, ETS1, IL-6, and COL1A1. Conclusions. The present study identified six hub genes that were related to lung cancer, including mTOR, NF1, CHD7, ETS1, IL-6, and COL1A1, which might be a potential target for lung cancer.

In photosynthesis, the protein-bound natural oxygen-evolving center (OEC) undergoes multiple oxidation-state transitions in the light-driven water splitting reactions with a stepwise change in the oxidation potential. Because the protein is vulnerable to electrochemical oxidation, the multiple oxidation/reduction-state transitions can hardly be achieved by electrochemical oxidation with a continuous change in the oxidation potential. An OEC mimic that can undergo four redox transitions has been synthesized (Zhang, C., Science, 2015, 348, 690-693). Here we report an electrochemical FTIR spectroscopic study of this synthetic complex at its multiple oxidation states in the low-frequency region for Mn-O bonds. Compared with those of the native OEC induced by pulsed laser flashes, our results also show the existence of two structural isomers in the S2 state, with the closed cubane conformer being more stable than the open cubane conformer, in contrast to that of the native OEC in which the open form is more stable.

Relying on an inhibitor-based probe, we reveal the clustered distribution of membrane PSMA by dSTORM imaging and uncover its potential interaction with folate receptor. This inhibitor-based strategy realizes more accurate labeling than antibody labeling, which would make it a powerful tool in the field of dSTORM imaging.

Epithelial cell adhesion molecule (EpCAM) is an important type I transmembrane protein that is overexpressed on the surfaces of most cancer cells and involved in various biological processes such as cell adhesion and cell signaling. Although it plays crucial roles in cell functions and tumorigenesis, questions concerning the detailed morphology, molecular stoichiometry, and the assembly mechanisms of EpCAM on cell membranes have not been fully elucidated. Here, we used direct stochastic optical reconstruction microscopy (dSTORM) and relied on fluorophore-conjugated peptides to quantitatively analyze the assembly pattern of EpCAM with single-molecule precision. EpCAM was found to organize heterogeneous clusters with different sizes, which contain different numbers of EpCAM molecules on MCF-7 cell membranes. Moreover, dual-color dSTORM imaging revealed a significant correlation between EpCAM and tetraspanin CD9, and part of the EpCAM clusters could be disrupted by knockdown of CD9, which indicated that EpCAM might localize in tetraspanin-enriched microdomains (TEMs) and function cooperatively with CD9 on cell membranes. In addition, the assembly of the membrane EpCAM was found to be limited by both cytoskeleton and glycosylation. Overall, our work clarified the clustered distribution of EpCAM and revealed the potential mechanisms of its clustering at the molecular level, promoting a deeper understanding of the nano-organization of membrane proteins.

Circular RNAs (circRNAs) are related to the progression of non-small cell lung cancer (NSCLC). However, the roles and mechanism of circ_0006988 are largely unknown. The levels of circ_0006988, Low-Density Lipoprotein Receptor Class A Domain Containing 3 (LDLRAD3), microRNA-491-5p (miR-491-5p), Mitogen-Activated Protein Kinase Kinase Kinase 3 (MAP3K3) were measured using quantitative real-time polymerase-chain reaction (qRT-PCR) and western blot assay. The characteristic of circ_0006988 was analyzed by RNase R assay and Actinomycin D assay. Functional analyses were processed by Cell Counting Kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay, colony formation assay, flow cytometry analysis, transwell assay, wound-healing assay and tube formation assay. The interactions between circ_0006988 and miR-491-5p as well as miR-491-5p and MAP3K3 were analyzed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Murine xenograft model assay was processed to verify the function of circ_0006988 in vivo. Immunohistochemistry (IHC) assay was conducted to examine the level of Ki67. Circ_0006988 abundance was increased in NSCLC tissues and cells. Circ_0006988 silencing restrained NSCLC cell proliferation, migration, invasion and angiogenesis, and induced apoptosis. Circ_0006988 sponged miR-491-5p, which directly targeted MAP3K3. MiR-491-5p overexpression repressed NSCLC cell malignant behaviors. MiR-491-5p downregulation or MAP3K3 overexpression reversed the effect of circ_0006988 silencing on NSCLC cell progression. In addition, circ_0006988 knockdown reduced xenograft tumor growth. ssCirc_0006988 contributed to the development of NSCLC by miR-491-5p/MAP3K3 axis.

Additional file 1: Table S1. Primer sequences used in qRT-PCR. Figure S1. (A) GEPIA website shows the expression of BBOX1-AS1 in LUSC. (B) starBase Pan-Cancer Analysis Platform reveals the expression of miR-27a-5p in LUSC. (C) starBase Pan-Cancer Analysis Platform was used to analyze the correlation between miR-27a-5p and BBOX1-AS1 in lung cancer tissues. (D) Kaplan-Meier survival plots using the TCGA LUAD and LUSC patients by expression value of miR-27a-5p. (E) Kaplan-Meier survival curve was used to determine the correlation between overall survival and miR-27a-5p expression in NSCLC. (F) GEPIA database displays the expression of MELK mRNA in LUSC and LUAD. Figure S2. MELK promotes cell proliferation, migration and invasion in NSCLC. (A-D) A549 and SK-MES-1 cells were transfected with si-NC or si-MELK, followed by CCK-8 assay of cell viability (A), colony forming assay (B), wound healing assay of cell migration (C) and transwell assay of cell invasion. **P

Circular RNAs (circRNAs) play a significant role in the progression of diverse malignancies. Here, we aimed to probe the function and mechanism of circ_0069244 in non-small cell lung cancer (NSCLC). In the present study, circ_0069244 was selected from the circRNA microarray datasets (GSE112214). Quantitative real-time polymerase chain reaction (qRT-PCR) was applied to examine circ_0069244, miR-346 and XPC complex subunit, DNA damage recognition and repair factor (XPC) expression levels. Kaplan-Meier curve was employed to analyze the association between circ_0069244 expression and overall survival of NSCLC patients. Cell counting kit-8 (CCK-8) and 5-Bromo-2'-deoxyuridine (BrdU) experiments were utilized to examine the proliferation of NSCLC cells. Scratch healing and Transwell experiments were executed to examine the migration of NSCLC cells. Western blot was conducted to detect XPC expression at protein level in NSCLC cells. Bioinformatics analysis, dual-luciferase reporter gene and RNA immunoprecipitation (RIP) experiments predicted and validated the targeting relationships of circ_0069244 and miR-346, as well as miR-346 and 3'untranslated region (UTR) of XPC mRNA, respectively. We reported that circ_0069244 was remarkably down modulated in NSCLC and was linked to shorter survival and poor tumor histological grade in NSCLC patients. Functionally, circ_0069244 repressed NSCLC cell proliferation and migration. Furthermore, miR-346-5p was unveiled to be a downstream target of circ_0069244, and miR-346-5p specifically modulated XPC expression. Rescue experiments indicated that the inhibitory effect of circ_0069244 was abolished by co-expression of miR-346-5p mimics. Taken together, circ_0069244 restrained NSCLC progression by modulating the miR-346-5p/XPC axis.

Membrane fusion is fundamental to biological activity of cells, so disclosingits relevant mechanism is very important for understanding various cell functions. Although artificial model systems have been developed to uncover the mechanism of membrane fusion, key factors determining the mode of membrane fusion remain unclear. Based on the construction of different types of liposome vesicles, we used a dynamic fluorescence imaging method to investigate the effect of membrane protein distribution density on membrane fusion. Time-resolved imaging revealed that protein-free pure phospholipid vesicles themselves occurred full membrane fusion. Moreover, we prepared proteoliposomes with increasing protein-to-lipid ratio to better reflect the characteristic of membrane structure in vivo. Our data showed that pure phospholipid vesicles no longer fused with the proteoliposomes that in a higher protein proportion, indicating dense membrane proteins may hinder membrane fusion. A further comparative analysis of the interactions of pure phospholipid vesicles with the cell membrane / giant plasma membrane vesicles (GPMVs) / protein-free giant unilamellar vesicles (GUVs) confirmed the inhibitory effect of dense membrane proteins on membrane fusion. Our work demonstrates the membrane protein density influences the mode of membrane fusion and lays a foundation for constructing quasi-native membrane fusion models in vitro.

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is a serious respiratory disease, the mechanism is unclear. This paper revealed the mechanism of ganoderic acid B (BB) on lipopolysaccharide-induced pneumonia in mice. Pneumonia model was induced by LPS in mice and A549 cells. Lung dry/wet weight (W/D) and myeloperoxidase (MPO) activity in lung were examined. Lung histopathological changes was observed by HE staining. Superoxide dismutase (SOD), malondialdehyde (MDA) and proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) in mice and A549 cells were detected. Rho/NF-κB pathway in mice and A549 cells were examined by Western Blot. BB significantly reduced W/D and MPO activity, restored lung histopathological changes. BB also increased SOD, decreased MDA, TNF-α, IL-1β and IL-6 in mice and A549 cells. In addition, BB inhibited Rho/NF-κB pathway in mice and A549 cells. BB has protective effect on LPS-induced pneumonia in mice, and its mechanism is related to the regulation of Rho/NF-κB signaling pathway.

Aptamers, referred to as “chemical antibodies”, are short single-stranded oligonucleotides that bind to targets with high affinity and specificity. Compared with antibodies, aptamers can be designed, developed and modified easily. Since their discovery, aptamers have been widely used in in vitro diagnostics and molecular imaging. However, they are relatively less studied and applied in advanced microscopy. Here we used an RNA aptamer in dSTORM imaging and obtained a high-quality image of EGFR nanoscale clusters on live cell membranes. The results showed that the cluster number and size with aptamer labeling were almost the same as those with labeling with the natural ligand EGF, but the morphology of the clusters was smaller and more regular than that with cetuximab labeling. Meanwhile, dual-color imaging demonstrated sufficient fluorophore labeling, highly specific recognition and greatly accurate clustering information provided by aptamers. Furthermore, the aptamer labeling method indicated that active EGFR formed larger clusters containing more molecules than resting EGFR, which was hidden under the antibody labeling. Our work suggested that aptamers can be used as versatile probes in super-resolution imaging with small steric hindrance, opening a new avenue for detailed and precise morphological analysis of membrane proteins.

Nucleolin (NCL) is a multifunctional protein that mainly localizes in the nucleolus and also distributes in the nucleoplasm, cytoplasm and cell membrane. Most studies focus on its biofunctions in cell activities and diseases, however, its detailed distribution and organization pattern in situ remains obscure. Moreover, antibodies were commonly used to investigate NCL in cells. It is worth noting that antibody labeling of intracellular proteins needs detergents to permeabilize the membrane, which could disrupt the membrane structure and proteins. The emergence of aptamer AS1411 provides us a good choice to recognize the NCL without permeabilization owing to its superior cellular uptake and enhanced stability. Therefore, we applied aptamer AS1411 to super-resolution imaging to visualize the distribution of NCL at a nanometer level. Aptamer achieved a better recognition of intracellular NCL and displayed the detailed structure of NCL in different parts of cells. Significantly, cytoplasmic and membrane NCL have higher expression and larger clusters in cancer cells than that in normal cells. Our work presented a detailed organization of NCL in cells and revealed the distribution differences between cancer cells and normal cells, which promote the understanding of its functions in physiology and pathology.

Cetuximab is a monoclonal antibody that binds to the epidermal growth factor receptor, which is important in the growth of many cancers. However, the biophysical characteristics of cetuximab as an anti-cancer drug remain elusive. In this study, we adopted atomic force microscopy to measure the mechanical properties of cancer cells following cetuximab treatment and the biomechanical properties of cetuximab and epidermal growth factor receptor interactions. Atomic force microscopy can be implemented as a platform for further investigations that target the cellular stiffness and affinity of ligand-receptor as a therapeutic choice.

Phosphate (P) fixed on Fe- and Al-(hydr)oxides can be released into solution by coexisting anions or molecules that have strong reactivity with the mineral surfaces. Bacteria have been shown to adhere strongly on to the (hydr)oxides through physical or chemical forces, or both. It is still unknown, however, whether bacteria can desorb P from oxides. We examined the desorption of P from haematite (α-Fe2O3) by Bacillus subtilis and Pseudomonas fluorescens through the combined use of in-situ attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy and macroscopic batch experiments. The ATR-FTIR data of ternary bacteria–P–haematite systems indicated a release of P that was concurrent with the attachment of bacteria on to the haematite surface, giving direct and in-situ evidence for the displacement of P by bacteria. The P-desorbing ability of bacteria was quantified by batch desorption experiments, and was further supported by the inhibitory role of bacteria in P adsorption on to haematite under varying concentrations of P and amounts of bacteria. In-situ ATR-FTIR investigations and Derjaguin–Landau–Verwey–Overbeek (DLVO) prediction suggested that bacteria might compete for sorption sites with P through their electrostatic and chemical interactions (coordination of bacterial phosphate and carboxyl groups on the haematite surface) with the haematite surface. In addition, the bacteria reduced greatly the positive charge of haematite, and the reduction correlated non-linearly with the decline in P adsorption. Therefore, the P-mobilizing ability of bacteria is probably attributed to the competition between P and bacterial surface groups and reduction in the positive charge on haematite by bacteria. These findings elucidate a potential role for bacteria in mobilizing P that is chemically adsorbed on Fe-oxides, which enhances the availability of P to plants and its mobility in natural environments. Highlights Whether bacteria can desorb phosphate from oxides remained unknown. Bacteria enhanced desorption of phosphate from haematite and inhibited its adsorption by haematite. Electrostatic and chemical interactions might help bacteria compete with phosphate. Reduction in positive charges might also contribute to phosphate-mobilizing ability of bacteria.

The Hippo signaling pathway plays critical roles in many biological processes including mechanotransduction. The key activator YAP of this pathway is considered as a central component of mechanotransduction signaling sensing the extracellular mechanical microenvironment changes, such as different cell density, the architecture of tissues and matrix stiffness. Although it has been largely studied that YAP is involved in these processes, the underlying mechanism of mechanical force-induced YAP regulation remains unclear. Here we exerted pressure on cell surfaces and investigated how YAP senses the extracellular mechanical force change using one of the super-resolution imaging techniques, dSTORM. We demonstrated that pressure promoted F-actin depolymerization, RhoA down-regulation, and LPAR1 (Gα12/13-coupled receptor) inactivation, which led to YAP cytoplasmic translocation and decreased clustering. Our work uncovers the role of GPCRs and F-actin in pressure-controlled YAP inactivation, and provides new insights into the mechanisms of mechanical regulation of the Hippo signaling pathway.

This retrospective study aimed to investigate the association between programmed death ligand-1 (PD-L1) expression and the clinicopathological characteristics of patients with advanced epidermal growth factor receptor (EGFR) wild-type non-small cell lung cancer (NSCLC). The predictive role and cut-off value of PD-L1 expression was subsequently investigated. A total of 172 patients with advanced EGFR wild-type NSCLC were enrolled. All patients received platinum-based doublet chemotherapy (gemcitabine plus cisplatin). PD-L1 expression in lung tissues was assessed using immunohistochemical methods. The χ2 test was used to analyze the association between PD-L1 expression and clinicopathological characteristics. Survival time analysis was performed using the Kaplan-Meier method. The two groups, positive PD-L1 expression and negative PD-L1 expression, were compared using the log-rank test. Multivariate analysis using the Cox proportional hazard regression model was conducted to determine prognostic factors for overall survival (OS) and progression-free survival (PFS) times. Positive PD-L1 expression was observed in 48.3% (84/172), 40.7% (70/172), 21.5% (37/172) and 8.1% (14/172) of patients when using cut-off values of 1, 5, 10 and 50%, respectively. The χ2 test revealed that elevated pretreatment C-reactive protein (CRP) level and cancer stage IV were significantly associated with positive PD-L1 expression. The OS and PFS of positive PD-L1 (1, 5, 10 and 50% cut-off) expression group were shorter compared with the negative PD-L1 (1, 5, 10 and 50% cut-off) expression group. Multivariate survival analysis revealed that PD-L1 expression ≥50% was significantly associated with decreased OS and PFS [OS time, P=0.001; hazard ratio (HR), 2.768; 95% confidence interval (CI), 1.551–4.940; PFS time, P=0.002; HR, 2.537; 95% CI, 1.423–4.524]. These results indicated that positive PD-L1 (50% cut-off) expression was an independent predictor of poor prognosis for patients with advanced NSCLC treated with gemcitabine plus cisplatin. PD-L1 expression was associated with CRP level and cancer stage. The results obtained in the present study suggest that positive PD-L1 expression serves a prognostic role in advanced NSCLC and that the optimal cut-off value may be 50%.

The Analog Hadronic Calorimeter (AHCAL) is one option of highly granular calorimeters optimised with the Particle Flow Algorithm (PFA) and considered for experiments at future lepton colliders. It consists of dense steel plates as absorber interleaved with plastic scintillator tiles, individually read out by Silicon Photomultipliers (SiPMs). A novel SiPM developed by the Novel Device Laboratory (NDL) with an active area of 1 mm2 and a pixel pitch of 12.5 micron[NDL-SiPM-12.5] has been mainly investigated. The characterisation studies include single photon calibration, dynamic range and performance of crosstalk as well as Minimum Ionising Particle (MIP) detection efficiency of a detector unit. Combined tests with a dedicated ASIC (SPIROC2E) for multi-channel SiPMs show that single photon spectra can be obtained, given the relatively small SiPM gain (∼2 × 105). The linearity of the SiPMs in response to incident photons of less than 10,000 (500 MIPs) is within 5% from measurements. Meanwhile, the dark count rate (DCR) is around 2×10-3 Hz at a threshold 0.5 MIP (10 p.e.) and the MIP detection efficiency of a detector unit can be near 95% from the MIP spectrum. These studies indicate the NDL-SiPM-12.5 can be a photosensor candidate for the future scintillator-based hadronic calorimeters.

Advanced fluorescence microscopy including single-molecule localization-based super-resolution imaging techniques requires bright and photostable dyes or proteins as fluorophores. The photophysical properties of fluorophores have been proven to be crucial for super-resolution microscopy’s localization precision and imaging resolution. Fluorophores TAMRA and Atto Rho6G, which can interact with macrocyclic host cucurbit[7]uril (CB7) to form host-guest compounds, were found to improve the fluorescence intensity and lifetimes of these dyes. We enhanced the localization precision of direct stochastic optical reconstruction microscopy (dSTORM) by introducing CB7 into the imaging buffer, and showed that the number of photons as well as localizations of both TAMRA and Atto Rho6G increase over 2 times.

The Circular Electron Position Collider (CEPC) aims at precision measurements of Higgs, W and Z boson properties. High granularity calorimetry associated with Particle Flow Algorithm (PFA) aims at jet energy resolution around 30%/sE/GeV. One option for the Hadronic Calorimeter (HCAL) is the so-called Analog HCAL (AHCAL) which consists of stainless steel as the absorber and scintillators as the sensitive material. This talk presents the latest progress on the optimisation studies of the HCAL detector cell in terms of light output and uniformity. Simulation studies on the software compensation technique are also presented, which shows around 10% improvement of the energy resolution with hadrons. In addition, we tried out 8 iterations of polystyrene recipe prototyping and scintillator tiles production with the injection moulding technique and achieved scintillator uniformity within the same batch better than 90%. Effective and fast ways of integrating the detector cells are under development such as an automatic wrapping machine and a glue dispenser. Preliminary results have been made for a merged readout scheme, which may provide a feasible method to reduce the number of electronic channels.

The glucose transporter GLUT1, a plasma membrane protein that mediates glucose homeostasis in mammalian cells, is responsible for constitutive uptake of glucose into many tissues and organs. Many studies have focused on its vital physiological functions and close relationship with diseases. However, the molecular mechanisms of its activation and transport are not clear, and its detailed distribution pattern on cell membranes also remains unknown. To address these, we first investigated the distribution and assembly of GLUT1 at a nanometer resolution by super-resolution imaging. On HeLa cell membranes, the transporter formed clusters with an average diameter of ∼250 nm, the majority of which were regulated by lipid rafts, as well as being restricted in size by both the cytoskeleton and glycosylation. More importantly, we found that the activation of GLUT1 by azide or MβCD did not increase its membrane expression but induced the decrease of the large clusters. The results suggested that sporadic distribution of GLUT1 may facilitate the transport of glucose, implying a potential association between the distribution and activation. Collectively, our work characterized the clustering distribution of GLUT1 and linked its spatial structural organization to the functions, which would provide insights into the activation mechanism of the transporter.

Cell surface carbohydrates play significant roles in many physiological processes and act as primary markers to indicate various cellular physiological states. The functions of carbohydrates are always associated with their expression and distribution on cell membranes. Based on our previous work, we found that carbohydrates tend to form clusters; however, the underlying mechanism of these clusters remains unknown. Through the direct stochastic optical reconstruction microscopy (dSTORM) strategy, we found that with the contributions of lipid raft as a stable factor and actin cytoskeleton as a restrictive factor, carbohydrate clusters can stably exist with restricted size. Additionally, we revealed that the formation of most carbohydrate clusters (Gal and GlcANc clusters) depended on the carbohydrate-binding proteins (i.e., galectins) cross-linking their specific carbohydrate ligands. Our results clarify the organizational mechanism of carbohydrates on cell surfaces from their formation, stable existence and size-restriction, which promotes a better understanding of the relationship between the function and distribution of carbohydrates, as well as the structure of cell membranes.

Organic fluorescent dyes are widely used in single molecule localization microscopy, where their performances are determined by the photophysical properties. Herein, we utilized a sensitive method to modulate the fluorescence of organic dyes by external potentials using a combination of electrochemical cell and super-resolution fluorescent microscopy. Cy5 (cyanine dye) was chosen as a model molecule considering its wide application and commercial availability. We applied different potentials on the Au electrode to change the Coulombic charge microenvironment of Cy5. When the electrode potential was adjusted negatively, Cy5 displayed a better photostability. This method is proved effective in adjusting the fluorescence of organic dyes.

Carbohydrates are involved in various physiological and pathological activities including cell adhesion, signal transduction and tumor invasion. The distribution of carbohydrates is the molecular basis of their multiple functions, but remains poorly understood. Here, we employed direct stochastic optical reconstruction microscopy (dSTORM) to visualize the pattern of N-acetylglucosamine (N-GlcNAc) on Vero cell membranes at the nanometer level of resolution. We found that N-GlcNAcs exist in irregular clusters on the apical membrane with an average cluster area of about 0.37 μm(2). Most of these N-GlcNAc clusters are co-localized with lipid rafts by dual-color dSTORM imaging, suggesting that carbohydrates are closely associated with lipid rafts as the functional domains. Our results demonstrate that super-resolution imaging is capable of characterizing the distribution of carbohydrates on the cellular surface at the molecular level.

Yes-associated protein (YAP) is well known for being an effecter of the Hippo signaling cascade that plays a critical role in organ size control, tumorigenesis, and regeneration. As YAP is a transcriptional coactivator, nuclear accumulation is a crucial determinant of its function. Numerous investigations have provided insights into the regulation of YAP, such as upstream molecules of the Hippo pathway, cell contact inhibition, and mechanical forces. However, detailed information regarding YAP spatial localization and organization in cells remains uncertain, and how mechanical signals control YAP distribution and function is not fully known. Therefore, we used one of the super-resolution imaging techniques, direct stochastic optical reconstruction microscopy (dSTORM), combined with confocal microscopy, to solve these problems. We found that YAP is mainly distributed in clusters in the cells, and that both cell contact and pressure on cell surfaces promote the nuclear-to-cytoplasm translocation of YAP and its phosphorylation, but weaken the clustering of nuclear YAP and its transcriptional activity. Moreover, we found that pressure regulation may be more effective on YAP from cancer cells as compared to normal cells, which could help open a door to target YAP for anticancer drug design.

High manufacturing costs and weak cell selectivity have limited the clinical application of naturally occurring peptides when faced with an outbreak of drug resistance. To overcome these limitations, a set of antimicrobial peptides was synthesized with the general sequence of (WL)n, where n = 1, 2, 3, and WL was truncated from the N-terminus of Cecropin P1 without initial serine residues. The antimicrobial peptide WL3 exhibited stronger antimicrobial activity against both Gram-negative and Gram-positive microbes than the parental peptide CP-1. WL3 showed no hemolysis even at the highest test concentrations compared to the parental peptide CP-1. The condition sensitivity assays (salts, serum, and trypsin) demonstrated that WL3 had high stability in vitro. Fluorescence spectroscopy and electron microscopy indicated that WL3 killed microbes by means of penetrating the membrane and causing cell lysis. In a mouse model, WL3 was able to significantly reduce the bacteria load in major organs and cytokines (TNF-α, IL-6, and IL-1β) levels in serum. In summary, these findings suggest that WL3, which was modified from a natural antimicrobial peptide, has enormous potential for application as a novel antibacterial agent.

Derived from Panax ginseng, the natural product 20(S)-Protopanaxadiol (PPD) has been reported for its cytotoxicity against several cancer cell lines. The molecular mechanism is, however, not well understood. Here we show that PPD significantly inhibits proliferation, induces apoptosis and causes G2/M cell cycle arrest in human laryngeal carcinoma cells (Hep-2 cells). PPD also decreases the levels of proteins related to cell proliferation. Moreover, PPD-induced apoptosis is characterized by a dose-dependent down-regulation of Bcl-2 expression and up-regulation of Bax, and is accompanied by the activation of Caspase-3 as well. Further molecular mechanism is revealed by direct stochastic optical reconstruction microscopy (dSTORM)—a novel high-precision localization microscopy which enables effective resolution down to the order of 10 nm. It shows the expression and spatial arrangement of mTOR and its downstream effectors, demonstrating that this ginsenoside exerts its excellent anticancer effects via down-regulation of mTOR signaling pathway in Hep-2 cells. Taken together, our findings elucidate that the antitumor effect of PPD is associated with its regulation of mTOR expression and distribution, which encourages further studies of PPD as a promising therapeutic agent against laryngeal carcinoma.

Because antimicrobial peptides (AMPs) are potentially useful for the treatment of multidrug-resistant infections, more attention is being paid to the structural modification and structure–function relationship of both naturally occurring and synthetic AMPs. Previous studies indicated that Protegrin-1 (PG-1), isolated from porcine leukocytes, exhibited considerable antimicrobial activity and cytotoxicity. The β-turn of PG-1 floated on the surface of bacterial membrane, while its β-strand inserted into the bacterial membrane and formed pores that were dedicated to producing cytotoxicity. For reducing cytotoxicity and improving cells selectivity, we designed a series of simplified symmetric-end peptides by combining the β-turn of PG-1 with simple amino acid repeat sequences. The sequence of designed symmetric-end peptides is (XR)nH(RX)n, (n = 1,2; X represents I, F, W and P; H represents CRRRFC). The symmetric-end peptides displayed antimicrobial activity against both gram-positive and gram-negative bacteria. In particular, (XR)2H(RX)2 (X here is I, F and W) showed greater antimicrobial potency than PG-1. Hemolysis activity and cytotoxicity, detected by using human red blood cells (RBCs) and human embryonic lung fibroblasts MRC-5 cells, were observably lower than the native peptide PG-1. (IR)2H(RI)2 (IR2), folded into β-sheet structures, displayed the highest therapeutic index, suggesting its great cell selectivity. The fluorescence spectroscopy, flow cytometry, and electron microscopy observation indicated that IR2 exhibited great membrane penetration potential by inducing membrane blebbing, disruption and lysis. Collectively, generating symmetric-end β-sheet peptides is a promising strategy for designing effective AMPs with great antimicrobial activities and cell selectivity.

The cell membrane provides critical cellular functions that rely on its elaborate structure and organization. The structure of turtle membranes is an important part of an ongoing study of erythrocyte membranes. Using a combination of atomic force microscopy and single-molecule force spectroscopy, we characterized the turtle erythrocyte membrane structure with molecular resolution in a quasi-native state. High-resolution images both leaflets of turtle erythrocyte membranes revealed a smooth outer membrane leaflet and a protein covered inner membrane leaflet. This asymmetry was verified by single-molecule force spectroscopy, which detects numerous exposed amino groups of membrane proteins in the inner membrane leaflet but much fewer in the outer leaflet. The asymmetric membrane structure of turtle erythrocytes is consistent with the semi-mosaic model of human, chicken and fish erythrocyte membrane structure, making the semi-mosaic model more widely applicable. From the perspective of biological evolution, this result may support the universality of the semi-mosaic model.

The interaction forces and binding kinetics between SIRPα and CD47 were investigated by single-molecule force spectroscopy (SMFS) on both fresh and experimentally aged human red blood cells (hRBCs). We found that CD47 experienced a conformation change after oxidation, which influenced the interaction force and the position of the energy barrier between SIRPα and CD47. Our results are significant for understanding the mechanism of phagocytosis of red blood cells at the single molecule level.

A simple one-step chemical bath process was developed to fabricate Cu 2 ZnSnS 4 (CZTS) thin films. Effects of pH value and ZnCl 2 precursor content on the formation of CZTS were investigated. The best process parameters were a pH value of 3.5–4 and a ZnCl 2 content of 1.75 mmoL for deposition of high quality of CZTS films. The films consist of kesterite phase CZTS nanocrystals and exhibit a band-gap of ∼1.48 eV. A conversion efficiency of 0.30% was achieved in one of the CZTS thin film solar cells. The route developed here may provide an alternative approach to produce low-cost and large area solar cells.

Cu 2 ZnSnS 4 (CZTS) nanocrystals were synthesized with a simple solution method. The effects of the amount of oleylamine, the quantity of zinc salt precursor and reaction time on the structure, composition, morphology and optical properties of the nanocrystals were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray analysis (EDX) measurements. The zinc content in the nanocrystals increases with the increasing of the amount of oleylamine and the quantity of ZnCl 2 precursor. But the particle sizes were influenced mainly by the reaction time. For dye-sensitized solar cells (DSSCs) using CZTS nanocrystals as the dye layer, the J SC was greatly decreased with the increasing of the sizes of the nanocrystals. Synthesis of small and uniformly dispersed CZTS nanocrystals was beneficial to enhance the power conversion efficiency of the DSSCs.

Carbohydrate alterations on cell membranes are associated with various cancer processes, including tumorigenesis, malignant transformation, and tumor dissemination. However, variations in the distributions of cancer-associated carbohydrates are unclear at the molecular level. Herein, direct stochastic optical reconstruction microscopy is used to reveal that seven major types of carbohydrates tended to form obvious clusters on cancer cell membranes compared with normal cell membranes (both cultured and primary cells), and most types of carbohydrates present a similar distributed characteristic on various cancer cells (e.g., HeLa and Os-Rc-2 cells). Significantly, sialic acid is found to distribute in larger-sized clusters with a higher cluster coverage percentage on various cancer cells than normal cells. These findings on the aberrant distributions of cancer-associated carbohydrates can potentially serve as novel diagnostic and therapeutic targets, as well as making a contribution to clarify how abnormal glycosylations of membrane glycoconjugates participate in tumorigenesis and metastasis.