Diffusion model predicts the geometry of actin cytoskeleton from cell morphology.

Cells exhibit various morphological characteristics due to their physiological activities, and changes in cell morphology are inherently accompanied by the assembly and disassembly of the actin cytoskeleton. Stress fibers are a prominent component of the actin-based intracellular structure and are highly involved in numerous physiological processes, e.g., mechanotransduction and maintenance of cell morphology. Although it is widely accepted that variations in cell morphology interact with the distribution and localization of stress fibers, it remains unclear if there are underlying geometric principles between the cell morphology and actin cytoskeleton. Here, we present a machine learning system that uses the diffusion model to convert the cell shape to the distribution and alignment of stress fibers. By training with corresponding cell shape and stress fibers datasets, our system learns the conversion to generate the stress fiber images from its corresponding cell shape. The predicted stress fiber distribution agrees well with the experimental data. With this conversion relation, our system allows for performing virtual experiments that provide a visual map showing the probability of stress fiber distribution from the virtual cell shape. Our system potentially provides a powerful approach to seek further hidden geometric principles regarding how the configuration of subcellular structures is determined by the boundary of the cell structure; for example, we found that the stress fibers of cells with small aspect ratios tend to localize at the cell edge while cells with large aspect ratios have homogenous distributions.

Self-Sensing Electromechanical System Integrated with the Embedded Displacement Sensor.

Conventionally, the electromechanical system requires the installation of auxiliary displacement sensors and only the amount on the drive part and motion end, which increases volume, cost, and measurement error in the system. This paper presents an integrated measurement method with a sensing head, which takes the equal division characteristics of mechanical structures as part of the sensor, thus, the so-called self-sensing system. Moreover, the displacement is measured by counting the time pulses. The sensing head is integrated with the entire electromechanical system, including the driving, transmitting, and moving parts. Thus, the integration of the sensing part is greatly improved. Taking the rotary table as a special example, and the sensing head embedded into each part of the system, displacement information is obtained by the common processing system and fused by the adaptive weighted average method. The results of the experiment show that the fusion precision of each component is higher than only the motor position information as the feedback. The proposed method is a practical self-sensing technology with significant volume reduction and intelligent control benefits in the industry, especially suitable for extremely small and narrow spaces.

Comprehensive analysis on the whole Rho-GAP family reveals that ARHGAP4 suppresses EMT in epithelial cells under negative regulation by Septin9.

Epithelial to mesenchymal transition (EMT) is a fundamental biological process that occurs during development and tumorigenesis. The Rho family of GTPases (Rho-family) is a well-characterized regulator of actin cytoskeleton that gives rise to EMT-associated cell activities. Meanwhile, there are in total at least 66 different Rho-GTPase-activating proteins (Rho-GAPs), which, as an upstream regulator, inactivate specific members of the Rho-family in a cell context-dependent manner. However, molecular roles of individual Rho-GAPs are poorly understood, particularly regarding their involvements in EMT. Here, based on comprehensive screening on the whole Rho-GAP family, we identified specific Rho-GAPs that are responsible for the maintenance of epithelial cell phenotypes, suppressing EMT in human mammary epithelial cells. Specifically, we revealed that at least two Rho-GAPs, that is, ARHGAP4 and SH3BP1, critically regulate the cell morphology. Among them, we focused on ARHGAP4 and demonstrated with multidisciplinary approaches that this specific Rho-GAP regulates epithelial/mesenchymal-selective marker expression, cell proliferation, migration, 3D morphogenesis, and focal adhesion/stress fiber-driven physical force generation in a manner reminiscent of the EMT process. Furthermore, we identified Septin9 with proteomic analyses as a negative regulator of ARHGAP4, which promotes the occurrence of EMT by activation of the FAK/Src signaling pathway. These findings shed light on the novel Rho-GAP-associated pathway in the EMT process under development and tumorigenesis.

Spatiotemporal patterns of hemorrhagic fever with renal syndrome in Hebei Province, China, 2001-2016.

Hemorrhagic fever with renal syndrome (HFRS) is highly endemic in China, where approximately 90% of the total human cases in the world are reported. The Hebei province, one of areas with the highest prevalence, has reported HFRS cases every year in the last two decades. This study describes the spatiotemporal patterns of HFRS in the Hebei province from 2001 to 2016, detects the high-risk spatiotemporal clusters of HFRS, and provides valuable information for planning and implementation of local preventive measures. For the purpose of the analysis, HFRS cases recorded during the sixteen years in the Hebei province were aggregated into three temporal periods (2001-2006, 2007-2012, and 2013-2016). Spatiotemporal analyses, including Global spatial autocorrelation analysis and Kulldorff's scan statistical analysis, were applied to analyze te spatiotemporal clusters of HFRS at the county level. The results revealed that the spatial extent of the HFRS epidemic in the Hebei province changed dynamically from 2001 to 2016, which indicated that a comprehensive preventative strategy should be implemented in the northeastern regions of the Hebei province in spring.

Long-term retrospective observation reveals stabilities and variations of hantavirus infection in Hebei, China.

BACKGROUND: Hemorrhagic fever with renal syndrome (HFRS) is an emerging zoonotic infectious disease caused by hantaviruses which circulate worldwide. So far, it was still considered as one of serious public health problems in China. The present study aimed to reveal the stabilities and variations of hantavirus infection in Hebei province located in North China through a long-term retrospective observation. METHODS: The epidemiological data of HFRS cases from all 11 cities of Hebei province since 1981 through 2016 were collected and descriptively analyzed. The rodent densities, species compositions and virus-carrying rates of different regions were collected from six separated rodent surveillance points which set up since 2007. The molecular diversity and phylogenetic relationship of hantaviruses circulating among rodents were analyzed based on partial viral glycoprotein gene. RESULTS: HFRS cases have been reported every year in Hebei province, since the first local case was identified in 1981. The epidemic history can be artificially divided into three phases and a total of 55,507 HFRS cases with 374 deaths were reported during 1981-2016. The gender and occupational factors of susceptible population were invarible throughout, however age of that was gradually aging. The annual outbreak peak always present in spring, while the main epidemic region had gradully altered from south to northeast. Surveillance of rodents revealed that residential rodents significantly possessed higher density and virus-carring rate than field rodents. The house rat, Rattus norvegicus, was the dominant rodent species and Seoul virus S3 sub-genotype which is continued but slightly evolving perhaps to be the sole pathogen for local HFRS cases of Hebei province. CONCLUSIONS: This long-term province-wide surveillance and epidemiological analysis has revealed the stabilities and variations of hantavirus infection in North China. In order to improve current prevention and control strategies of HFRS in China, all surveillance should be continuously enhanced and variations should be paid more attentions.

Evolution of mitosome metabolism and invasion-related proteins in Cryptosporidium.

BACKGROUND: The switch from photosynthetic or predatory to parasitic life strategies by apicomplexans is accompanied with a reductive evolution of genomes and losses of metabolic capabilities. Cryptosporidium is an extreme example of reductive evolution among apicomplexans, with losses of both the mitosome genome and many metabolic pathways. Previous observations on reductive evolution were largely based on comparative studies of various groups of apicomplexans. In this study, we sequenced two divergent Cryptosporidium species and conducted a comparative genomic analysis to infer the reductive evolution of metabolic pathways and differential evolution of invasion-related proteins within the Cryptosporidium lineage. RESULTS: In energy metabolism, Cryptosporidium species differ from each other mostly in mitosome metabolic pathways. Compared with C. parvum and C. hominis, C. andersoni possesses more aerobic metabolism and a conventional electron transport chain, whereas C. ubiquitum has further reductions in ubiquinone and polyisprenoid biosynthesis and has lost both the conventional and alternative electron transport systems. For invasion-associated proteins, similar to C. hominis, a reduction in the number of genes encoding secreted MEDLE and insulinase-like proteins in the subtelomeric regions of chromosomes 5 and 6 was also observed in C. ubiquitum and C. andersoni, whereas mucin-type glycoproteins are highly divergent between the gastric C. andersoni and intestinal Cryptosporidium species. CONCLUSIONS: Results of the study suggest that rapidly evolving mitosome metabolism and secreted invasion-related proteins could be involved in tissue tropism and host specificity in Cryptosporidium spp. The finding of progressive reduction in mitosome metabolism among Cryptosporidium species improves our knowledge of organelle evolution within apicomplexans.

Comparative genomics reveals Cyclospora cayetanensis possesses coccidia-like metabolism and invasion components but unique surface antigens.

BACKGROUND: Cyclospora cayetanensis is an apicomplexan that causes diarrhea in humans. The investigation of foodborne outbreaks of cyclosporiasis has been hampered by a lack of genetic data and poor understanding of pathogen biology. In this study we sequenced the genome of C. cayetanensis and inferred its metabolism and invasion components based on comparative genomic analysis. RESULTS: The genome organization, metabolic capabilities and potential invasion mechanism of C. cayetanensis are very similar to those of Eimeria tenella. Propanoyl-CoA degradation, GPI anchor biosynthesis, and N-glycosylation are some apparent metabolic differences between C. cayetanensis and E. tenella. Unlike Eimeria spp., there are no active LTR-retrotransposons identified in C. cayetanensis. The similar repertoire of host cell invasion-related proteins possessed by all coccidia suggests that C. cayetanensis has an invasion process similar to the one in T. gondii and E. tenella. However, the significant reduction in the number of identifiable rhoptry protein kinases, phosphatases and serine protease inhibitors indicates that monoxenous coccidia, especially C. cayetanensis, have limited capabilities or use a different system to regulate host cell nuclear activities. C. cayetanensis does not possess any cluster of genes encoding the TA4-type SAG surface antigens seen in E. tenella, and may use a different family of surface antigens in initial host cell interactions. CONCLUSIONS: Our findings indicate that C. cayetanensis possesses coccidia-like metabolism and invasion components but unique surface antigens. Amino acid metabolism and post-translation modifications of proteins are some major differences between C. cayetanensis and other apicomplexans. The whole genome sequence data of C. cayetanensis improve our understanding of the biology and evolution of this major foodborne pathogen and facilitate the development of intervention measures and advanced diagnostic tools.

Small longitudinal S incision and page turning style of annular ligament partial resection to treat stenosing tenosynovitis of thumb flexor tendon.

BACKGROUND: To present the treatment outcome for patients with stenosing tenosynovitis of thumb flexor tendon treated with a small S incision and page turning style of annular ligament partial resection. MATERIAL AND METHODS: During a 2-year period between August 2011 and July 2013, 12 consecutive patients (mean age, 45.8 years) with stenosing tenosynovitis of the thumb flexor tendon were prospectively enrolled into this study. All 12 patients underwent longitudinal S skin incision to expose annular ligament and thumb flexor tendon, and with page turning style of annular ligament partial resection to finish the operation. The average range of motion of metacarpophalangeal thumb joint, Quick disability of arm, shoulder, and hand and Short Musculoskeletal Function Assessment Dysfunction score of arm and hand were primary outcome measures. RESULTS: There were 9 cases of stiff metacarpophalangeal joint of thumb and 3 cases of snapping thumb for stenosing tenosynovitis. At 1-year follow-up, all stenosing tenosynovitis had healed by an average of 4 weeks. The average range of motion of the metacarpophalangeal joint was 37.1° (range, 34-40°). No patients had recurrence, cicatricial contraction, or postoperative infection. The average disability of arm, shoulder, and hand was 0.3 out of 100 (range, 0-1.67), and average Short Musculoskeletal Functional Assessment Dysfunction score of arm and hand was 6.9 out of 40 (range, 0-15.6). All 12 patients stated that they were highly satisfied. CONCLUSIONS: Small S incision and page turning style of annular ligament partial resection for stenosing tenosynovitis of thumb flexor tendon is a safe, simple, and reliable alternative treatment with minimal soft-tissue irritation, good functional results and recovery can be expected.

Incorporation of graphene oxide in quantum dot sensitized photocatalyst based on ZnO nanorods.

The novel efficient architecture of photocatalyst is fabricated by incorporating graphene oxide (GO) in quantum dots (QDs) sensitized ZnO nanorods and the photocatalytic properties for methyl orange (MO) degradation are investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis-NIR absorption spectroscopy. The results indicate that the incorporating of grapheme oxide is more favourable for the degradation. The improved photocatalytic properties can take several advantages given that the higher carrier mobility of GO which can reduce the recombination of carriers, and assembled quantum dots which can facilitate the absorption of solar light. The paper provides the clue to design the effective and easy recyclable photocatalyst.

Synthesis and optical properties of Eu3+ doped ZnO nanoparticles used for white light emitting diodes.

ZnO nanoparticles doped with trivalent europium ions (Eu3+) were synthesized by the hydrothermal method. The structural properties of the samples were investigated by the X-ray diffraction (XRD). The results indicated that Eu3+ was incorporated into the lattice of ZnO. Photoluminescence (PL) measurements of ZnO:Eu3+ showed a strong red luminescence emission. Specially, the red emission can be obtained even under the nonresonant excitation of 320 nm, and it is explained by an energy transfer mechanism in which the energy is transferred from ZnO matrix to Eu3+. These results indicate that the ZnO:Eu3+ is the attractive candidate phosphor for the application in phosphor-converted light-emitting diodes (pc-LEDs) as red phosphor. The intensity of Eu3+ PL decreased with the increasing Eu3+ concentration and the concentration quenching mechanism was presented based on non-radiative recombination processes in ZnO and the energy back-transfer from the excited state of Eu3+ to the ZnO host. Moreover, the samples were synthesized under low temperature condition.

The complete mitochondrial genome and phylogenetic analysis of Rattus tanezumi (Niethammer, 1975), captured from North China.

Rattus tanezumi (Niethammer, 1975) is one of the commensal rodent species in South China. With the development of transportation and climate change, R. tanezumi has gradually migrated north and become the dominant rat species for the past few years. In this study, we assembled a complete mitochondrial genome of R. tanezumi, captured from North China. The mitogenome contains 16,307 nucleotide pairs, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, as well as one non-coding control region. Based on whole mitogenome phylogenetical analysis showed that R. tanezumi captured from North China had a close phylogenetic relationship with that from Japan and South Korea. These findings are valuable for further studies on the evolution, genetic diversity, and taxonomy of Asian commensal rodent.

Sensitivity analysis of RT-qPCR and RT-ddPCR for SARS-CoV-2 detection with mutations on N1 and E primer-probe region.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an RNA virus that undergoes rapid mutation. Based on viral whole genome sequencing analysis in Hebei Province, China, we identified several essential single nucleotide variants (SNVs) on primer-probe regions accumulating within some Omicron variants' genomes. In this study, we focused on three SNVs, C28290T, T28297C, and C28311T emerging on 2019-nCoV-N1 (CDC-N1) primer-probe regions, recommended by CDC in 2020, and two SNVs, C26270T, A26275G emerging on E (Charité-E) primer-probe regions recommended by Charité, Germany. Our findings revealed that the presence of one or two SNVs in the primer or probe region affected the sensitivity of reverse transcription-quantitative polymerase chain reaction and droplet digital PCR to varying extents. This discovery underscores the importance of continuously monitoring the whole genome sequences of SARS-CoV-2 variants, especially the primer-probe targeting regions, and correspondingly updating commercial test kits or recommended primer-probe sequence sets. IMPORTANCE: The emergence of new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has resulted in a growing number of mutations in its genome, presenting new challenges for the diagnosis of SARS-CoV-2 using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and droplet digital PCR (RT-ddPCR) methods. There is an urgent need to develop refined methods for modifying primers and probes to improve the detection of these emerging variants. In this study, our focus was on the SNVs that have emerged in the CDC-N1 and Charité-E primer-probe regions. Our research has confirmed that the presence of these SNVs in the primer or probe region can significantly affect the results of coronavirus disease 2019 tests. we have developed and validated a modified detection method that can provide higher sensitivity and specificity. This study emphasizes the importance of refining the primer-probe sets to ensure the diagnostic accuracy of RT-qPCR and RT-ddPCR detection.

Surveillance of SARS-CoV-2 in wastewater by quantitative PCR and digital PCR: a case study in Shijiazhuang city, Hebei province, China.

In this study, we reported the first long-term monitoring of SARS-CoV-2 in wastewater in Mainland China from November 2021 to October 2023. The city of Shijiazhuang was employed for this case study. We developed a triple reverse transcription droplet digital PCR (RT-ddPCR) method using triple primer-probes for simultaneous detection of the N1 gene, E gene, and Pepper mild mottle virus (PMMoV) to achieve accurate quantification of SARS-CoV-2 RNA in wastewater. Both the RT-ddPCR method and the commercial multiplex reverse transcription quantitative polymerase chain reaction (RT-qPCR) method were implemented for the detection of SARS-CoV-2 in wastewater in Shijiazhuang City over a 24-month period. Results showed that SARS-CoV-2 was detected for the first time in the wastewater of Shijiazhuang City on 10 November 2022. The peak of COVID-19 cases occurred in the middle of December 2022, when the concentration of SARS-CoV-2 in the wastewater was highest. The trend of virus concentration increases and decreases forming a "long-tailed" shape in the COVID-19  outbreak and recession cycle. The results indicated that both multiplex RT-ddPCR and RT-qPCR are effective in detecting SARS-CoV-2 in wastewater, but RT-ddPCR is capable of detecting low concentrations of SARS-CoV-2 in wastewater which is more efficient. The SARS-CoV-2 abundance in wastewater is correlated to clinical data, outlining the public health utility of this work.HighlightsFirst long-term monitoring of SARS-CoV-2 in wastewater in Mainland ChinaCOVID-19 outbreak was tracked in Shijiazhuang City from outbreak to containmentWastewater was monitored simultaneously using RT-ddPCR and RT-qPCR methodsTriple primer-probe RT-ddPCR detects N1 and E genes of SARS-CoV-2 and PMMoV.

Stereo-Hindrance Engineering of A Cation toward <110>-Oriented 2D Perovskite with Minimized Tilting and High-Performance X-Ray Detection.

2D <100>-oriented Dion-Jacobson or Ruddlesden-Popper perovskites are widely recognized as promising candidates for optoelectronic applications. However, the large interlayer spacing significantly hinders the carrier transport. <110>-oriented 2D perovskites naturally exhibit reduced interlayer spacings, but the tilting of metal halide octahedra is typically serious and leads to poor charge transport. Herein, a <110>-oriented 2D perovskite EPZPbBr4 (EPZ = 1-ethylpiperazine) with minimized tilting is designed through A-site stereo-hindrance engineering. The piperazine functional group enters the space enclosed by the three [PbBr6]4- octahedra, pushing Pb─Br─Pb closer to a straight line (maximum Pb─Br─Pb angle ≈180°), suppressing the tilting as well as electron-phonon coupling. Meanwhile, the ethyl group is located between layers and contributes an extremely reduced effective interlayer distance (2.22 Å), further facilitating the carrier transport. As a result, EPZPbBr4 simultaneously demonstrates high µτ product (1.8 × 10-3 cm2 V-1) and large resistivity (2.17 × 1010 Ω cm). The assembled X-ray detector achieves low dark current of 1.02 × 10-10 A cm-2 and high sensitivity of 1240 µC Gy-1 cm-2 under the same bias voltage. The realized specific detectivity (ratio of sensitivity to noise current density, 1.23 × 108 µC Gy-1 cm-1 A-1/2) is the highest among all reported perovskite X-ray detectors.

Enhanced photocatalytic activity of quantum-dot-sensitized one-dimensionally-ordered ZnO nanorod photocatalyst.

An efficient photocatalyst was fabricated by assembling quantum dots (QDs) onto one-dimensionally-ordered ZnO nanorods, and the photocatalytic properties for Methyl Orange degradation were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, UV-Vis-NIR absorption spectroscopy and photoluminescence. The results indicate that the catalyst with assembled QDs is more favorable for the degradation than the pristine ZnO nanorods. The QDs with core-shell structure lower the photocatalytic ability due to the higher carrier transport barrier of the ZnS shell layer. Besides its degradation efficiency, the photocatalyst has several advantages given that the one-dimensionally-ordered ZnO nanorods have been grown directly on indium tin oxide substrates. The article provides a new method to design an effective and easily recyclable photocatalyst.

Expression of angiotensin converting enzyme 2 mRNA in different SARS-CoV-2 infection states and times.

To measure the expression of angiotensin converting enzyme 2 (ACE2) mRNA in SARS-CoV-2 infection with different infection status and at different stages during infection, we used RT-qP CR to measure the expression of ACE2 mRNA. Measurements were analyzed by two-way repeated measures analysis of variance (RMANOVA). Expression of ACE2 mRNA was downregulated in initial stages of SARS-CoV-2 infection both in the asymptomatic infection (ASY) group and the confirmed cases (CON) group (t=-8.0845, P < 0.0001; t=-8.1904, P < 0.0001, respectively). The expression of ACE2 mRNA in the incubation period of CON group was lower compared with the intinal period of ASY group (F = 6.084, p = 0.016, partialη2 = 0.070). Relative expression of ACE2 mRNA was upregulated at the late stage of SARS-CoV-2 infection in the ASY and CON groups (F = 23.489, p = 0.000, partialη2 = 0.225; F = 46.555, p = 0.000, partialη2 = 0.365, respectively). The relative expression of ACE2 mRNA was down-regulated (mean ± SEM:0.69 ± 0.03) after inoculation with SARSCoV- 2 Spike pseudovirus, and there was a statistical difference (one-way t test, mean diffience =-0.31, 95%CI: -0.37˜-0.24, t=-8.1904, P < 0.0001). The expression of ACE2 mRNA is downregulated in the initial stage of SARS-CoV-2 infection, and then upregulated in the late stage of SARS-CoV-2 infection. The lower expression of ACE2 mRNA during the incubation period can lead to clinical symptoms. Downregulation of ACE2 mRNA was related to the interaction between SARS-CoV-2 S protein and ACE2.Communicated by Ramaswamy H. Sarma.

Analysis of senescence-responsive stress fiber proteome reveals reorganization of stress fibers mediated by elongation factor eEF2 in HFF-1 cells.

Stress fibers (SFs), which are actomyosin structures, reorganize in response to various cues to maintain cellular homeostasis. Currently, the protein components of SFs are only partially identified, limiting our understanding of their responses. Here we isolate SFs from human fibroblasts HFF-1 to determine with proteomic analysis the whole protein components and how they change with replicative senescence (RS), a state where cells decline in the ability to replicate after repeated divisions. We found that at least 135 proteins are associated with SFs, and 63 of them are up-regulated with RS, by which SFs become larger in size. Among them, we focused on eEF2 (eukaryotic translation elongation factor 2) as it exhibited on RS the most significant increase in abundance. We show that eEF2 is critical to the reorganization and stabilization of SFs in senescent fibroblasts. Our findings provide a novel molecular basis for SFs to be reinforced to resist cellular senescence.

Field Evaluation of a Duplex RT-RAA Assay for Rapid Detection of SARS-CoV-2 - Hebei Province, China, January 2021.

Introduction: Recently, a local cluster epidemic has occurred in Shijiazhuang City, Hebei Province. Failure to promptly identify patients with fever in rural areas was the major reason for this epidemic. Methods: We presented the field evaluation of a new real-time reverse transcription recombinase-aided amplification (RT-RAA) kit incorporating an endogenous internal control in a single-tube format, completed at the Hebei CDC from January 17, 2021 to January 27, 2021. Results: We evaluated the diagnostic performance of RT-RAA assay using automatic extracted RNA of 808 clinical samples. Compared with reverse transcriptase real-time quantitative PCR (qRT-PCR), RT-RAA kit achieved 92.41% sensitivity, 98.78% specificity and a 96.29% coincidence rate, demonstrating an excellent agreement between the RT-RAA assay and qRT-PCR assay. Furthermore, 58 samples were extracted using a manual extraction method within 5 minutes, but only samples with high nucleic acid concentration (cycle threshold value not higher than 32) could be stably detected. Discussion: The RT-RAA is more suitable to meet the needs of rapid, sensitive, and accurate detection in community-level medical institutions.

ARHGAP4-SEPT2-SEPT9 complex enables both up- and down-modulation of integrin-mediated focal adhesions, cell migration, and invasion.

The Rho family of GTPases are inactivated in a cell context-dependent manner by Rho-GTPase-activating proteins (Rho-GAPs), but their signaling mechanisms are poorly understood. Here we demonstrate that ARHGAP4, one of the Rho-GAPs, forms a complex with SEPT2 and SEPT9 via its Rho-GAP domain and SH3 domain to enable both up- and down-modulation of integrin-mediated focal adhesions (FAs). We show that silencing ARHGAP4 and overexpressing its two mutually independent upstream regulators, SEPT2 and SEPT9, all induce reorganization of FAs to newly express Integrin Beta 1 and also enhance both cell migration and invasion. Interestingly, even if these cell migration/invasion-associated phenotypic changes are induced upon perturbations to the complex, it does not necessarily cause enhanced clustering of FAs. Instead, its extent depends on whether the microenvironment contains ligands suitable for the up-regulated Integrin Beta 1. These results provide novel insights into cell migration, invasion, and microenvironment-dependent phenotypic changes regulated by the newly identified complex.

EphA2 super-enhancer promotes tumor progression by recruiting FOSL2 and TCF7L2 to activate the target gene EphA2.

Super-enhancers or stretch enhancers (SEs) consist of large clusters of active transcription enhancers which promote the expression of critical genes that define cell identity during development and disease. However, the role of many super-enhancers in tumor cells remains unclear. This study aims to explore the function and mechanism of a new super-enhancer in various tumor cells. A new super-enhancer that exists in a variety of tumors named EphA2-Super-enhancer (EphA2-SE) was found using multiple databases and further identified. CRISPR/Cas9-mediated deletion of EphA2-SE results in the significant downregulation of its target gene EphA2. Mechanistically, we revealed that the core active region of EphA2-SE comprises E1 component enhancer, which recruits TCF7L2 and FOSL2 transcription factors to drive the expression of EphA2, induce cell proliferation and metastasis. Bioinformatics analysis of RNA-seq data and functional experiments in vitro illustrated that EphA2-SE deletion inhibited cell growth and metastasis by blocking PI3K/AKT and Wnt/ß-catenin pathway in HeLa, HCT-116 and MCF-7 cells. Overexpression of EphA2 in EphA2-SE-/- clones rescued the effect of EphA2-SE deletion on proliferation and metastasis. Subsequent xenograft animal model revealed that EphA2-SE deletion suppressed tumor proliferation and survival in vivo. Taken together, these findings demonstrate that EphA2-SE plays an oncogenic role and promotes tumor progression in various tumors by recruiting FOSL2 and TCF7L2 to drive the expression of oncogene EphA2.