The growing prevalence of fake images on the Internet and social media makes image integrity verification a crucial research topic.One of the most popular methods for manipulating digital images is image splicing,whic...The growing prevalence of fake images on the Internet and social media makes image integrity verification a crucial research topic.One of the most popular methods for manipulating digital images is image splicing,which involves copying a specific area from one image and pasting it into another.Attempts were made to mitigate the effects of image splicing,which continues to be a significant research challenge.This study proposes a new splicing detectionmodel,combining Sonine functions-derived convex-based features and deep features.Two stages make up the proposed method.The first step entails feature extraction,then classification using the“support vector machine”(SVM)to differentiate authentic and spliced images.The proposed Sonine functions-based feature extraction model reveals the spliced texture details by extracting some clues about the probability of image pixels.The proposed model achieved an accuracy of 98.93% when tested with the CASIA V2.0 dataset“Chinese Academy of Sciences,Institute of Automation”which is a publicly available dataset for forgery classification.The experimental results show that,for image splicing forgery detection,the proposed Sonine functions-derived convex-based features and deep features outperform state-of-the-art techniques in terms of accuracy,precision,and recall.Overall,the obtained detection accuracy attests to the benefit of using the Sonine functions alongside deep feature representations.Finding the regions or locations where image tampering has taken place is limited by the study.Future research will need to look into advanced image analysis techniques that can offer a higher degree of accuracy in identifying and localizing tampering regions.展开更多
Background:In our previous study,we observed a synergistic effect of 2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-glucoside combined with adriamycin to induce apoptosis in MCF-7 breast cancer cells.However,the underlying me...Background:In our previous study,we observed a synergistic effect of 2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-glucoside combined with adriamycin to induce apoptosis in MCF-7 breast cancer cells.However,the underlying mechanisms of epigenetic modifications,such as alternative splicing,have not been explored.In this study,we aimed to investigate the mechanism by which THSG inhibits MCF-7 cell proliferation using full-length transcriptome sequencing.Methods:First,cell viability was examined using the methyl thiazolyl tetrazolium method and full-length transcriptome sequencing was performed to identify genes and pathways.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to identify the principal pathways and targets of THSG.Flow cytometry analysis of cell cycle distribution was performed.Meanwhile,the analysis of alternative splicing and domains of the key proteins was conducted.Quantitative polymerase chain reaction and western blotting were performed for verification.Results:THSG showed significant cytotoxic activity in MCF-7 cells.Full-length transcriptome sequencing revealed differential alternative splicing with 173 upregulated and 263 downregulated genes.Further analysis identified distinct differential expression of genes(CHEK2-211 and CCND1-201)involved in the cell cycle in the THSG-treated group.Subsequently,alternative splicing types of CHEK2(mutually exclusive exon)and CCND1(intron retention).We found that THSG downregulated mRNA expression,as confirmed by quantitative polymerase chain reaction analysis.Interestingly,protein structural analysis revealed that THSG treatment led to the generation of CHK2-211,which was the result of a mutation in the amino acid residues(GLU-150,ASN-151)of the CHEK2 domain(VAL-150,GLY-151).and CyclinD1-201 were obtained when an amino acid(ASP-267)in the domain was lost in CyclinD1.Moreover,molecular docking analysis demonstrated that the domains of key proteins could bind THSG more effectively,with no difference in affinity.Western blotting confirmed that THSG inhibited the expression of CHK2 and CyclinD1.Conclusion:THSG modulated the alternative splicing of CHEK2 and CCND1 by inducing G0/G1 cell cycle arrest,consequently suppressing MCF-7 cell proliferation.展开更多
Obtaining precise position of interested emitters passively has wide applications in both civilian and military fields.Different from traditional parameter measurement and direct position determination(DPD)method,rece...Obtaining precise position of interested emitters passively has wide applications in both civilian and military fields.Different from traditional parameter measurement and direct position determination(DPD)method,recently a new passive localization method based on synthetic aper-ture technique,named synthetic aperture positioning(SAP),has been proposed.The method com-pensates for the nonlinear phase produced by relative motion between the moving platform and the emitter,achieving coherent summation of intercepted signals.The SAP can obtain high-resolution and high-precision localization results at a low signal-to-noise ratio.This paper summarizes the research progress of SAP,including localization principles,spaceborne applications,and application scope analysis.Besides,the possible future outlook of SAP is considered.展开更多
The existing direction-of-arrival(DOA)estimation methods only utilize the current received signals,which are susceptible to noise.In this paper,a method for DOA estimation based on a motion platform is proposed to ach...The existing direction-of-arrival(DOA)estimation methods only utilize the current received signals,which are susceptible to noise.In this paper,a method for DOA estimation based on a motion platform is proposed to achieve high-precision DOA estimation by utilizing past and present signals.The concept of synthetic aperture is introduced to construct a linear DOA estima-tion model.A DOA fine-tuning method based on the linear model is proposed to eliminate the lin-ear DOA variation,achieving a non-coherent accumulation of DOA estimations.Moreover,the baseband modulation and the phase modulation caused by the range history are compensated to achieve the coherent accumulation of all the DOA estimations.Simulation results show that the proposed method can significantly improve the DOA estimated accuracy at low signal-to-noise ratios(SNR).展开更多
Metastasis remains a major challenge in the successful management of malignant diseases.The liver is a major site of metastatic disease and a leading cause of death from gastrointestinal malignancies such as colon,sto...Metastasis remains a major challenge in the successful management of malignant diseases.The liver is a major site of metastatic disease and a leading cause of death from gastrointestinal malignancies such as colon,stomach,and pancreatic cancers,as well as melanoma,breast cancer,and sarcoma.As an important factor that influences the development of metastatic liver cancer,alternative splicing drives the diversity of RNA transcripts and protein subtypes,which may provide potential to broaden the target space.In particular,the dysfunction of splicing factors and abnormal expression of splicing variants are associated with the occurrence,progression,aggressiveness,and drug resistance of cancers caused by the selective splicing of specific genes.This review is the first to provide a detailed summary of the normal splicing process and alterations that occur during metastatic liver cancer.It will cover the role of alternative splicing in the mechanisms of metastatic liver cancer by examining splicing factor changes,abnormal splicing,and the contribution of hypoxia to these changes during metastasis.展开更多
The firmness of table grape berries is a crucial quality parameter. Despite extensive research on postharvest fruit softening, its precise molecular mechanisms remain elusive. To enhance our comprehension of the under...The firmness of table grape berries is a crucial quality parameter. Despite extensive research on postharvest fruit softening, its precise molecular mechanisms remain elusive. To enhance our comprehension of the underlying molecular factors, we initially identified differentially expressed genes(DEGs) by comparing the transcriptomes of folic acid(FA)-treated and water-treated(CK) berries at different time points. We then analyzed the sequences to detect alternatively spliced(AS) genes associated with postharvest softening. A total of 2,559 DEGs were identified and categorized into four subclusters based on their expression patterns, with subcluster-4 genes exhibiting higher expression in the CK group compared with the FA treatment group. There were 1,045 AS-associated genes specific to FA-treated berries and 1,042 in the CK-treated berries, respectively. Gene Ontology(GO) annotation indicated that the AS-associated genes in CK-treated berries were predominantly enriched in cell wall metabolic processes,particularly cell wall degradation processes. Through a comparison between treatment-associated AS genes and subcluster-4 DEGs, we identified eight genes, including Pectinesterase 2(VvPE2, Vitvi15g00704), which encodes a cell wall-degrading enzyme and was predicted to undergo an A3SS event. The reverse transcription polymerase chain reaction further confirmed the presence of a truncated transcript variant of VvPE2 in the FA-treated berries.Our study provides a comprehensive analysis of AS events in postharvest grape berries using transcriptome sequencing and underscores the pivotal role of VvPE2 during the postharvest storage of grape berries.展开更多
The aperture of natural rock fractures significantly affects the deformation and strength properties of rock masses,as well as the hydrodynamic properties of fractured rock masses.The conventional measurement methods ...The aperture of natural rock fractures significantly affects the deformation and strength properties of rock masses,as well as the hydrodynamic properties of fractured rock masses.The conventional measurement methods are inadequate for collecting data on high-steep rock slopes in complex mountainous regions.This study establishes a high-resolution three-dimensional model of a rock slope using unmanned aerial vehicle(UAV)multi-angle nap-of-the-object photogrammetry to obtain edge feature points of fractures.Fracture opening morphology is characterized using coordinate projection and transformation.Fracture central axis is determined using vertical measuring lines,allowing for the interpretation of aperture of adaptive fracture shape.The feasibility and reliability of the new method are verified at a construction site of a railway in southeast Tibet,China.The study shows that the fracture aperture has a significant interval effect and size effect.The optimal sampling length for fractures is approximately 0.5e1 m,and the optimal aperture interpretation results can be achieved when the measuring line spacing is 1%of the sampling length.Tensile fractures in the study area generally have larger apertures than shear fractures,and their tendency to increase with slope height is also greater than that of shear fractures.The aperture of tensile fractures is generally positively correlated with their trace length,while the correlation between the aperture of shear fractures and their trace length appears to be weak.Fractures of different orientations exhibit certain differences in their distribution of aperture,but generally follow the forms of normal,log-normal,and gamma distributions.This study provides essential data support for rock and slope stability evaluation,which is of significant practical importance.展开更多
In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes consid...In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes considerable coherence with the SAR transmission waveform together with periodical modulation patterns.This paper develops an MISRJ suppression algorithm for SAR imagery with online dictionary learning.In the algorithm,the jamming modulation temporal properties are exploited with extracting and sorting MISRJ slices using fast-time autocorrelation.Online dictionary learning is followed to separate real signals from jamming slices.Under the learned representation,time-varying MISRJs are suppressed effectively.Both simulated and real-measured SAR data are also used to confirm advantages in suppressing time-varying MISRJs over traditional methods.展开更多
Managing server lost circulation is a major challenge of drilling operation in naturally fractured formations and it causes much nonproductive rig time. When encountered with loss, the fracture aperture intersecting t...Managing server lost circulation is a major challenge of drilling operation in naturally fractured formations and it causes much nonproductive rig time. When encountered with loss, the fracture aperture intersecting the wellbore is not well-identified in time, which has a significant impact on the decision of drilling operation and the undesired result of loss curing. Therefore, the onset of fracture is identified in a timely manner and evaluated comprehensively to formulate an appropriate strategy over time. However, the mud loss date, which is the primary source of information retrieved from the drilling process, was not properly used in real-time prediction of fracture aperture. This article provides a detailed mathematical study to discuss the mechanism of mud invasion in the near-wellbore region and prediction of fracture aperture. The fracture aperture can be calculated from mud-loss data by solving a cubic equation with input parameters given by the well radius, the overpressure ratio, and the maximum mud-loss volume. It permits the proper selection of loss-circulation material (LCM) with respect to particle size distribution and fiber usage. The case study illustrates the applicability of this methodology with a discussion on LCM particle distribution in different scenarios and the result demonstrates the outcome of inappropriate LCM usage and the advantages of the novel fiber-based LCM treatment.展开更多
This article discusses the roadbed splicing for hub interchanges.The article starts with a description of the characteristics of junction roadbed splicing.The application of splicing technology is explained using a su...This article discusses the roadbed splicing for hub interchanges.The article starts with a description of the characteristics of junction roadbed splicing.The application of splicing technology is explained using a subgrade splicing scheme of a project.Roadbed splicing involves stepwise excavation and preparative measures like surface cleaning and backfilling.This article serves to provide a valuable reference for road and bridge construction and improve the quality of China’s road and bridge projects,so as to achieve sustainable development of the road and bridge engineering industry.展开更多
Background:Hepatocellular carcinoma(HCC)is the fourth leading cause of cancer-related deaths globally.Splicing factor proline and glutamine-rich(SFPQ)is a multifunctional protein that controls various biological funct...Background:Hepatocellular carcinoma(HCC)is the fourth leading cause of cancer-related deaths globally.Splicing factor proline and glutamine-rich(SFPQ)is a multifunctional protein that controls various biological functions.As a potential therapeutic target and a promising prognostic indicator,the potential effects and processes of SFPQ in HCC require further investigation.Methods:The RNA sequencing data were obtained from the Gene Expression Omnibus,International Cancer Genome Consortium,and The Cancer Genome Atlas databases to analyze SFPQ expression and differentially expressed genes(DEGs).We utilized the LinkedOmics database to identify co-expressed genes.A Venn diagram was constructed to determine the overlapping genes between the DEGs and the co-expressed genes.Functional enrichment analysis was performed on the overlapping genes and DEGs.Furthermore,our study involved functional enrichment analysis,a protein-protein interaction network analysis,and an analysis of immune cell infiltration.The cBioPortal and Tumor Immune Single-cell Hub were utilized to investigate the genetic alterations of SFPQ and the single-cell transcriptome visualization of the tumor microenvironment.A ceRNA network was established with the assistance of the ENCORI website.Finally,we elucidated the clinical significance of SFPQ in HCC by employing Kaplan-Meier survival analysis,univariate and multivariate Cox regression,and prognostic nomogram models.Results:The expression of SFPQ in HCC tissues was significantly elevated compared to normal tissues.GSEA results indicated that increased expression of SFPQ was associated with pathways related to HCC.The ceRNA network,including SFPQ,hsa-miR-101-3p,AC023043.4,AC124798.1,AC145207.5,and GSEC,was constructed with the assistance of ENCORI.High SFPQ expression was related to a poor prognosis in HCC and its subtypes.Univariate and multivariate Cox regression analysis showed that elevated SFPQ expression is an independent predictive factor.Conclusions:The overexpression of SFPQ may serve as a potential prognostic biomarker,indicating a poor prognosis in HCC.展开更多
Geraniol is an important contributor to the pleasant floral scent of tea products and one of the most abundant aroma compounds in tea plants;however,its biosynthesis and physiological function in response to stress in...Geraniol is an important contributor to the pleasant floral scent of tea products and one of the most abundant aroma compounds in tea plants;however,its biosynthesis and physiological function in response to stress in tea plants remain unclear.The proteins encoded by the full-length terpene synthase(CsTPS1)and its alternative splicing isoform(CsTPS1-AS)could catalyze the formation of geraniol when GPP was used as a substrate in vitro,whereas the expression of CsTPS1-AS was only significantly induced by Colletotrichum gloeosporioides and Neopestalotiopsis sp.infection.Silencing of CsTPS1 and CsTPS1-AS resulted in a significant decrease of geraniol content in tea plants.The geraniol content and disease resistance of tea plants were compared when CsTPS1 and CsTPS1-AS were silenced.Down-regulation of the expression of CsTPS1-AS reduced the accumulation of geraniol,and the silenced tea plants exhibited greater susceptibility to pathogen infection than control plants.However,there was no significant difference observed in the geraniol content and pathogen resistance between CsTPS1-silenced plants and control plants in the tea plants infected with two pathogens.Further analysis showed that silencing of CsTPS1-AS led to a decrease in the expression of the defense-related genes PR1 and PR2 and SA pathway-related genes in tea plants,which increased the susceptibility of tea plants to pathogens infections.Both in vitro and in vivo results indicated that CsTPS1 is involved in the regulation of geraniol formation and plant defense via alternative splicing in tea plants.The results of this study provide new insights into geraniol biosynthesis and highlight the role of monoterpene synthases in modulating plant disease resistance via alternative splicing.展开更多
Alternative splicing is the process of producing variably spliced mRNAs by choosing distinct combinations of splice sites within a messenger RNA precursor.This splicing enables mRNA from a single gene to synthesize di...Alternative splicing is the process of producing variably spliced mRNAs by choosing distinct combinations of splice sites within a messenger RNA precursor.This splicing enables mRNA from a single gene to synthesize different proteins,which have different cellular properties and functions and yet arise from the same single gene.A family of splicing factors,Serine-arginine rich proteins,are needed to initiate the assembly and activation of the spliceosome.Serine and arginine rich splicing factor 1,part of the arginine/serine-rich splicing factor protein family,can either activate or inhibit the splicing of mRNAs,depending on the phosphorylation status of the protein and its interaction partners.Considering that serine and arginine rich splicing factor 1 is either an activator or an inhibitor,this protein has been studied widely to identify its various roles in different diseases.Research has found that serine and arginine rich splicing factor 1 is a key target for neuroprotection,showing its promising potential use in therapeutics for neurodegenerative disorders.Furthermore,serine and arginine rich splicing factor 1 might be used to regulate cancer development and autoimmune diseases.In this review,we highlight how serine and arginine rich splicing factor 1 has been studied concerning neuroprotection.In addition,we draw attention to how serine and arginine rich splicing factor 1 is being studied in cancer and immunological disorders,as well as how serine and arginine rich splicing factor 1 acts outside the central or peripheral nervous system.展开更多
The gradient element of the aperture gradient map is utilized directly to generate the aperture shape without modulation.This process can be likened to choosing the direction of negative gradient descent for the gener...The gradient element of the aperture gradient map is utilized directly to generate the aperture shape without modulation.This process can be likened to choosing the direction of negative gradient descent for the generic aperture shape optimiza-tion.The negative gradient descent direction is more suitable under local conditions and has a slow convergence rate.To overcome these limitations,this study introduced conjugate gradients into aperture shape optimization based on gradient modulation.First,the aperture gradient map of the current beam was obtained for the proposed aperture shape optimiza-tion method,and the gradients of the aperture gradient map were modulated using conjugate gradients to form a modulated gradient map.The aperture shape was generated based on the modulated gradient map.The proposed optimization method does not change the optimal solution of the original optimization problem,but changes the iterative search direction when generating the aperture shape.The performance of the proposed method was verified using cases of head and neck cancer,and prostate cancer.The optimization results indicate that the proposed optimization method better protects the organs at risk and rapidly reduces the objective function value by ensuring a similar dose distribution to the planning target volume.Compared to the contrasting methods,the normal tissue complication probability obtained by the proposed optimization method decreased by up to 4.61%,and the optimization time of the proposed method decreased by 5.26%on average for ten cancer cases.The effectiveness and acceleration of the proposed method were verified through comparative experiments.According to the comparative experiments,the results indicate that the proposed optimization method is more suitable for clinical applications.It is feasible for the aperture shape optimization involving the proposed method.展开更多
Chinese cabbage is an economically important Brassica vegetable worldwide, and clubroot, which is caused by the soilborne protist plant pathogen Plasmodiophora brassicae is regarded as a destructive disease to Brassic...Chinese cabbage is an economically important Brassica vegetable worldwide, and clubroot, which is caused by the soilborne protist plant pathogen Plasmodiophora brassicae is regarded as a destructive disease to Brassica crops. Previous studies on the gene transcripts related to Chinese cabbage resistance to clubroot mainly employed RNA-seq technology,although it cannot provide accurate transcript assembly and structural information. In this study, PacBio RS II SMRT sequencing was used to generate full-length transcriptomes of mixed roots at 0, 2, 5, 8, 13, and 22 days after P. brassicae infection in the clubroot-resistant line DH40R. Overall, 39 376 high-quality isoforms and 26 270 open reading frames(ORFs) were identified from the SMRT sequencing data. Additionally, 426 annotated long noncoding RNAs(lncRNAs),56 transcription factor(TF) families, 1 883 genes with poly(A) sites and 1 691 alternative splicing(AS) events were identified. Furthermore, 1 201 of the genes had at least one AS event in DH40R. A comparison with RNA-seq data revealed six differentially expressed AS genes(one for disease resistance and five for defensive response) that are potentially involved in P. brassicae resistance. The results of this study provide valuable resources for basic research on clubroot resistance in Chinese cabbage.展开更多
Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)magnets.However,the field crosstalk between the two apertures pre...Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)magnets.However,the field crosstalk between the two apertures presents challenges.As the CEPC will work at four beam energies of Z,W,Higgs and ttbar mode,the DAQ magnets will operate at four field gradients spanning from 3.18 to 12.63 T/m.The first short quadrupole magnet prototype with the bore diameter of 76 mm and magnetic length of 1.0 m revealed the problems of large magnetic field harmonics and a magnetic center shift within the beam energy range.Accordingly,a compensation method was proposed in this work to solve the field crosstalk effect.By adjusting the gap height at the middle of the two apertures,the field harmonics and magnetic center shift are significantly reduced.After optimization,the short prototype was modified using a new scheme.The field simulations are validated from the magnetic measurement results.Further,the multipole field meets the requirements of the four beam energies.The detailed magnetic field optimization,field harmonics adjustment,and measurement results are presented herein.展开更多
Sacred lotus(Nelumbo nucifera)is a typical aquatic plant,belonging to basal eudicot plant,which is ideal for genome and genetic evolutionary study.Understanding lotus gene diversity is important for the study of molec...Sacred lotus(Nelumbo nucifera)is a typical aquatic plant,belonging to basal eudicot plant,which is ideal for genome and genetic evolutionary study.Understanding lotus gene diversity is important for the study of molecular genetics and breeding.In this research,public RNA-seq data and the annotated reference genome were used to identify the genes in lotus.A total of 26,819 consensus and 1,081 novel genes were identified.Meanwhile,a comprehensive analysis of gene alternative splicing events was conducted,and a total of 19,983“internal”alternative splicing(AS)events and 14,070“complete”AS events were detected in 5,878 and 5,881 multi-exon expression genes,respectively.Observations made from the AS events show the predominance of intron retention(IR)subtype of AS events representing 33%.IR is followed by alternative acceptor(AltA),alternative donor(AltD)and exon skipping(ES),highlighting the universality of the intron definition model in plants.In addition,functional annotations of the gene with AS indicated its relationship to a number of biological processes such as cellular process and metabolic process,showing the key role for alternative splicing in influencing the growth and development of lotus.The results contribute to a better understanding of the current gene diversity in lotus,and provide an abundant resource for future functional genome analysis in lotus.展开更多
In higher plants, the chloroplast is the most important organelle for photosynthesis and for numerous essential metabolic processes in the cell. Although many genes involved in chloroplast development have been identi...In higher plants, the chloroplast is the most important organelle for photosynthesis and for numerous essential metabolic processes in the cell. Although many genes involved in chloroplast development have been identified, the mechanisms underlying such development are not fully understood. In this study, a rice(Oryza sativa) mutant exhibiting pale green color and seedling lethality was isolated from a mutant library. The mutated gene was identified as an ortholog of THA8(thylakoid assembly 8) in Arabidopsis and maize. This gene is designated as OsTHA8 hereafter. OsTHA8 showed a typical pentatricopeptide repeat(PPR) characteristic of only four PPR motifs. Inactivation of OsTHA8 led to a deficiency in chloroplast development in the rice seedling stage. OsTHA8 was expressed mainly in young leaves and leaf sheaths.The OsTHA8 protein was localized to the chloroplast. Loss of function of OsTHA8 weakened the editing efficiency of ndhB-611/737 and rps8-182 transcripts under normal conditions. Y2H and BiFC indicated that OsTHA8 facilitates RNA editing by forming an editosome with multiple organellar RNA editing factor(OsMORF8) and thioredoxin z(OsTRXz), which function in RNA editing in rice chloroplasts. Defective OsTHA8 impaired chloroplast ribosome assembly and resulted in reduced expression of PEP-dependent genes and photosynthesis-related genes. Abnormal splicing of the chloroplast gene ycf3 was detected in ostha8. These findings reveal a synergistic regulatory mechanism of chloroplast biogenesis mediated by RNA, broaden the function of the PPR family, and shed light on the RNA editing complex in rice.展开更多
High resolution imaging is achieved using increasingly larger apertures and successively shorter wavelengths.Optical aperture synthesis is an important high-resolution imaging technology used in astronomy.Conventional...High resolution imaging is achieved using increasingly larger apertures and successively shorter wavelengths.Optical aperture synthesis is an important high-resolution imaging technology used in astronomy.Conventional long baseline amplitude interferometry is susceptible to uncontrollable phase fluctuations,and the technical difficulty increases rapidly as the wavelength decreases.The intensity interferometry inspired by HBT experiment is essentially insensitive to phase fluctuations,but suffers from a narrow spectral bandwidth which results in a lack of effective photons.In this study,we propose optical synthetic aperture imaging based on spatial intensity interferometry.This not only realizes diffraction-limited optical aperture synthesis in a single shot,but also enables imaging with a wide spectral bandwidth,which greatly improves the optical energy efficiency of intensity interferometry.And this method is insensitive to the optical path difference between the sub-apertures.Simulations and experiments present optical aperture synthesis diffraction-limited imaging through spatial intensity interferometry in a 100 nm spectral width of visible light,whose maximum optical path difference between the sub-apertures reaches 69λ.This technique is expected to provide a solution for optical aperture synthesis over kilometer-long baselines at optical wavelengths.展开更多
Late-stage ovarian cancer(OC)has a poor prognosis and a high metastasis rate,but the underlying molecular mechanism is unclear.RNA binding proteins(RBPs)play important roles in posttranscriptional regulation in the co...Late-stage ovarian cancer(OC)has a poor prognosis and a high metastasis rate,but the underlying molecular mechanism is unclear.RNA binding proteins(RBPs)play important roles in posttranscriptional regulation in the contexts of neoplasia and tumor metastasis.In this study,we explored the molecular functions of a canonical RBP,Transformer 2βhomolog(TRA2B),in cancer cells.TRA2B knockdown in HeLa cells and subsequent wholetranscriptome RNA sequencing(RNA-seq)analysis revealed the TRA2B-regulated alternative splicing(AS)profile.We disrupted TRA2B expression in epithelial OC cells and performed a series of experiments to confirm the resulting effects on OC cell proliferation,apoptosis and invasion.TRA2B-regulated AS was tightly associated with the mitotic cell cycle,apoptosis and several cancer pathways.Moreover,the expression of hundreds of genes was regulated by TRA2B,and these genes were enriched in the functions of cell proliferation,cell adhesion and angiogenesis,which are related to the malignant phenotype of OC.By integrating the alternatively spliced and differentially expressed genes,we found that AS events and gene expression were regulated independently.We then explored and validated the oncogenic functions of TRA2B by knocking down its expression in OC cells.The high TRA2B expression was associated with poor prognosis in patients with OC.In ovarian tissue,TRA2B expression showed a gradual increasing trend with increasing malignancy.We demonstrated the important roles of TRA2B in ovarian neoplasia and aggressive OC behaviors and identified the underlying molecular mechanisms,facilitating the targeted treatment of OC.展开更多
文摘The growing prevalence of fake images on the Internet and social media makes image integrity verification a crucial research topic.One of the most popular methods for manipulating digital images is image splicing,which involves copying a specific area from one image and pasting it into another.Attempts were made to mitigate the effects of image splicing,which continues to be a significant research challenge.This study proposes a new splicing detectionmodel,combining Sonine functions-derived convex-based features and deep features.Two stages make up the proposed method.The first step entails feature extraction,then classification using the“support vector machine”(SVM)to differentiate authentic and spliced images.The proposed Sonine functions-based feature extraction model reveals the spliced texture details by extracting some clues about the probability of image pixels.The proposed model achieved an accuracy of 98.93% when tested with the CASIA V2.0 dataset“Chinese Academy of Sciences,Institute of Automation”which is a publicly available dataset for forgery classification.The experimental results show that,for image splicing forgery detection,the proposed Sonine functions-derived convex-based features and deep features outperform state-of-the-art techniques in terms of accuracy,precision,and recall.Overall,the obtained detection accuracy attests to the benefit of using the Sonine functions alongside deep feature representations.Finding the regions or locations where image tampering has taken place is limited by the study.Future research will need to look into advanced image analysis techniques that can offer a higher degree of accuracy in identifying and localizing tampering regions.
基金This research was funded by the Science and Technology Project of Jiaxing City(2019AD32251,2020AY30010)Scientific Research Foundation of Traditional Chinese Medicine of Zhejiang Province(2021ZB291)+2 种基金Medical Scientific Research Foundation of Zhejiang Province(2020KY9482019)the 2023 Jiaxing Key Discipline of Medicine-Clinical Diagnostics(Supporting Subject 2023-ZC-002)Project of Education Commission of Hubei Province(D20202802,B2022192).
文摘Background:In our previous study,we observed a synergistic effect of 2,3,5,4’-Tetrahydroxystilbene-2-O-b-D-glucoside combined with adriamycin to induce apoptosis in MCF-7 breast cancer cells.However,the underlying mechanisms of epigenetic modifications,such as alternative splicing,have not been explored.In this study,we aimed to investigate the mechanism by which THSG inhibits MCF-7 cell proliferation using full-length transcriptome sequencing.Methods:First,cell viability was examined using the methyl thiazolyl tetrazolium method and full-length transcriptome sequencing was performed to identify genes and pathways.Gene Ontology and Kyoto Encyclopedia of Genes and Genomes were used to identify the principal pathways and targets of THSG.Flow cytometry analysis of cell cycle distribution was performed.Meanwhile,the analysis of alternative splicing and domains of the key proteins was conducted.Quantitative polymerase chain reaction and western blotting were performed for verification.Results:THSG showed significant cytotoxic activity in MCF-7 cells.Full-length transcriptome sequencing revealed differential alternative splicing with 173 upregulated and 263 downregulated genes.Further analysis identified distinct differential expression of genes(CHEK2-211 and CCND1-201)involved in the cell cycle in the THSG-treated group.Subsequently,alternative splicing types of CHEK2(mutually exclusive exon)and CCND1(intron retention).We found that THSG downregulated mRNA expression,as confirmed by quantitative polymerase chain reaction analysis.Interestingly,protein structural analysis revealed that THSG treatment led to the generation of CHK2-211,which was the result of a mutation in the amino acid residues(GLU-150,ASN-151)of the CHEK2 domain(VAL-150,GLY-151).and CyclinD1-201 were obtained when an amino acid(ASP-267)in the domain was lost in CyclinD1.Moreover,molecular docking analysis demonstrated that the domains of key proteins could bind THSG more effectively,with no difference in affinity.Western blotting confirmed that THSG inhibited the expression of CHK2 and CyclinD1.Conclusion:THSG modulated the alternative splicing of CHEK2 and CCND1 by inducing G0/G1 cell cycle arrest,consequently suppressing MCF-7 cell proliferation.
基金supported in part by the National Science Fund for Excellent Young Scholars(No.62222113)in part by the joint Funds of the National Natural Science Foundation of China(No.U22B2015)+1 种基金in part by the stabilization support of National Radar Signal Processing Laboratory(No.KGJ202203)in part by the Fundamental Research Funds for the Central Universities(No.ZDRC2004).
文摘Obtaining precise position of interested emitters passively has wide applications in both civilian and military fields.Different from traditional parameter measurement and direct position determination(DPD)method,recently a new passive localization method based on synthetic aper-ture technique,named synthetic aperture positioning(SAP),has been proposed.The method com-pensates for the nonlinear phase produced by relative motion between the moving platform and the emitter,achieving coherent summation of intercepted signals.The SAP can obtain high-resolution and high-precision localization results at a low signal-to-noise ratio.This paper summarizes the research progress of SAP,including localization principles,spaceborne applications,and application scope analysis.Besides,the possible future outlook of SAP is considered.
基金supported in part by the National Science Fund for Excel-lent Young Scholars(No.62222113)in part by the joint Funds of the National Natural Science Foundation of China(No.U22B2015)+1 种基金in part by the stabilization support of National Radar Signal Processing Laboratory(No.KGJ202203)in part by the Fundamental Research Funds for the Central Universities(No.ZDRC2004).
文摘The existing direction-of-arrival(DOA)estimation methods only utilize the current received signals,which are susceptible to noise.In this paper,a method for DOA estimation based on a motion platform is proposed to achieve high-precision DOA estimation by utilizing past and present signals.The concept of synthetic aperture is introduced to construct a linear DOA estima-tion model.A DOA fine-tuning method based on the linear model is proposed to eliminate the lin-ear DOA variation,achieving a non-coherent accumulation of DOA estimations.Moreover,the baseband modulation and the phase modulation caused by the range history are compensated to achieve the coherent accumulation of all the DOA estimations.Simulation results show that the proposed method can significantly improve the DOA estimated accuracy at low signal-to-noise ratios(SNR).
基金Supported by the National Natural Science Foundation of China,No.82002068,No.82272281the Natural Science Foundation of Guangdong Province,No.2021A1515010949.
文摘Metastasis remains a major challenge in the successful management of malignant diseases.The liver is a major site of metastatic disease and a leading cause of death from gastrointestinal malignancies such as colon,stomach,and pancreatic cancers,as well as melanoma,breast cancer,and sarcoma.As an important factor that influences the development of metastatic liver cancer,alternative splicing drives the diversity of RNA transcripts and protein subtypes,which may provide potential to broaden the target space.In particular,the dysfunction of splicing factors and abnormal expression of splicing variants are associated with the occurrence,progression,aggressiveness,and drug resistance of cancers caused by the selective splicing of specific genes.This review is the first to provide a detailed summary of the normal splicing process and alterations that occur during metastatic liver cancer.It will cover the role of alternative splicing in the mechanisms of metastatic liver cancer by examining splicing factor changes,abnormal splicing,and the contribution of hypoxia to these changes during metastasis.
基金financially supported by the National Natural Science Foundation of China(32202560 and 32302470)the Program for Innovative Research Team(in Science and Technology)in University of Henan Province+6 种基金China(21IRTSTHN021)the Natural Science Foundation of HenanChina(232300421112)the Program for Science&Technology Innovation Talents in Universities of Henan ProvinceChina(21HASTIT035)the PhD Research Startup Foundation of Henan University of Science and TechnologyChina(13480068 and 13480067)。
文摘The firmness of table grape berries is a crucial quality parameter. Despite extensive research on postharvest fruit softening, its precise molecular mechanisms remain elusive. To enhance our comprehension of the underlying molecular factors, we initially identified differentially expressed genes(DEGs) by comparing the transcriptomes of folic acid(FA)-treated and water-treated(CK) berries at different time points. We then analyzed the sequences to detect alternatively spliced(AS) genes associated with postharvest softening. A total of 2,559 DEGs were identified and categorized into four subclusters based on their expression patterns, with subcluster-4 genes exhibiting higher expression in the CK group compared with the FA treatment group. There were 1,045 AS-associated genes specific to FA-treated berries and 1,042 in the CK-treated berries, respectively. Gene Ontology(GO) annotation indicated that the AS-associated genes in CK-treated berries were predominantly enriched in cell wall metabolic processes,particularly cell wall degradation processes. Through a comparison between treatment-associated AS genes and subcluster-4 DEGs, we identified eight genes, including Pectinesterase 2(VvPE2, Vitvi15g00704), which encodes a cell wall-degrading enzyme and was predicted to undergo an A3SS event. The reverse transcription polymerase chain reaction further confirmed the presence of a truncated transcript variant of VvPE2 in the FA-treated berries.Our study provides a comprehensive analysis of AS events in postharvest grape berries using transcriptome sequencing and underscores the pivotal role of VvPE2 during the postharvest storage of grape berries.
基金This work was supported by the National Nature Science Foundation of China(Grant Nos.42177139 and 41941017)the Natural Science Foundation Project of Jilin Province,China(Grant No.20230101088JC).The authors would like to thank the anonymous reviewers for their comments and suggestions.
文摘The aperture of natural rock fractures significantly affects the deformation and strength properties of rock masses,as well as the hydrodynamic properties of fractured rock masses.The conventional measurement methods are inadequate for collecting data on high-steep rock slopes in complex mountainous regions.This study establishes a high-resolution three-dimensional model of a rock slope using unmanned aerial vehicle(UAV)multi-angle nap-of-the-object photogrammetry to obtain edge feature points of fractures.Fracture opening morphology is characterized using coordinate projection and transformation.Fracture central axis is determined using vertical measuring lines,allowing for the interpretation of aperture of adaptive fracture shape.The feasibility and reliability of the new method are verified at a construction site of a railway in southeast Tibet,China.The study shows that the fracture aperture has a significant interval effect and size effect.The optimal sampling length for fractures is approximately 0.5e1 m,and the optimal aperture interpretation results can be achieved when the measuring line spacing is 1%of the sampling length.Tensile fractures in the study area generally have larger apertures than shear fractures,and their tendency to increase with slope height is also greater than that of shear fractures.The aperture of tensile fractures is generally positively correlated with their trace length,while the correlation between the aperture of shear fractures and their trace length appears to be weak.Fractures of different orientations exhibit certain differences in their distribution of aperture,but generally follow the forms of normal,log-normal,and gamma distributions.This study provides essential data support for rock and slope stability evaluation,which is of significant practical importance.
基金supported by the National Natural Science Foundation of China(61771372,61771367,62101494)the National Outstanding Youth Science Fund Project(61525105)+1 种基金Shenzhen Science and Technology Program(KQTD20190929172704911)the Aeronautic al Science Foundation of China(2019200M1001)。
文摘In electromagnetic countermeasures circumstances,synthetic aperture radar(SAR)imagery usually suffers from severe quality degradation from modulated interrupt sampling repeater jamming(MISRJ),which usually owes considerable coherence with the SAR transmission waveform together with periodical modulation patterns.This paper develops an MISRJ suppression algorithm for SAR imagery with online dictionary learning.In the algorithm,the jamming modulation temporal properties are exploited with extracting and sorting MISRJ slices using fast-time autocorrelation.Online dictionary learning is followed to separate real signals from jamming slices.Under the learned representation,time-varying MISRJs are suppressed effectively.Both simulated and real-measured SAR data are also used to confirm advantages in suppressing time-varying MISRJs over traditional methods.
文摘Managing server lost circulation is a major challenge of drilling operation in naturally fractured formations and it causes much nonproductive rig time. When encountered with loss, the fracture aperture intersecting the wellbore is not well-identified in time, which has a significant impact on the decision of drilling operation and the undesired result of loss curing. Therefore, the onset of fracture is identified in a timely manner and evaluated comprehensively to formulate an appropriate strategy over time. However, the mud loss date, which is the primary source of information retrieved from the drilling process, was not properly used in real-time prediction of fracture aperture. This article provides a detailed mathematical study to discuss the mechanism of mud invasion in the near-wellbore region and prediction of fracture aperture. The fracture aperture can be calculated from mud-loss data by solving a cubic equation with input parameters given by the well radius, the overpressure ratio, and the maximum mud-loss volume. It permits the proper selection of loss-circulation material (LCM) with respect to particle size distribution and fiber usage. The case study illustrates the applicability of this methodology with a discussion on LCM particle distribution in different scenarios and the result demonstrates the outcome of inappropriate LCM usage and the advantages of the novel fiber-based LCM treatment.
文摘This article discusses the roadbed splicing for hub interchanges.The article starts with a description of the characteristics of junction roadbed splicing.The application of splicing technology is explained using a subgrade splicing scheme of a project.Roadbed splicing involves stepwise excavation and preparative measures like surface cleaning and backfilling.This article serves to provide a valuable reference for road and bridge construction and improve the quality of China’s road and bridge projects,so as to achieve sustainable development of the road and bridge engineering industry.
文摘Background:Hepatocellular carcinoma(HCC)is the fourth leading cause of cancer-related deaths globally.Splicing factor proline and glutamine-rich(SFPQ)is a multifunctional protein that controls various biological functions.As a potential therapeutic target and a promising prognostic indicator,the potential effects and processes of SFPQ in HCC require further investigation.Methods:The RNA sequencing data were obtained from the Gene Expression Omnibus,International Cancer Genome Consortium,and The Cancer Genome Atlas databases to analyze SFPQ expression and differentially expressed genes(DEGs).We utilized the LinkedOmics database to identify co-expressed genes.A Venn diagram was constructed to determine the overlapping genes between the DEGs and the co-expressed genes.Functional enrichment analysis was performed on the overlapping genes and DEGs.Furthermore,our study involved functional enrichment analysis,a protein-protein interaction network analysis,and an analysis of immune cell infiltration.The cBioPortal and Tumor Immune Single-cell Hub were utilized to investigate the genetic alterations of SFPQ and the single-cell transcriptome visualization of the tumor microenvironment.A ceRNA network was established with the assistance of the ENCORI website.Finally,we elucidated the clinical significance of SFPQ in HCC by employing Kaplan-Meier survival analysis,univariate and multivariate Cox regression,and prognostic nomogram models.Results:The expression of SFPQ in HCC tissues was significantly elevated compared to normal tissues.GSEA results indicated that increased expression of SFPQ was associated with pathways related to HCC.The ceRNA network,including SFPQ,hsa-miR-101-3p,AC023043.4,AC124798.1,AC145207.5,and GSEC,was constructed with the assistance of ENCORI.High SFPQ expression was related to a poor prognosis in HCC and its subtypes.Univariate and multivariate Cox regression analysis showed that elevated SFPQ expression is an independent predictive factor.Conclusions:The overexpression of SFPQ may serve as a potential prognostic biomarker,indicating a poor prognosis in HCC.
基金This research was funded by National Key Research and Development Program of China(2021YFD1601103 and 2022YFF1003103)National Natural Science Foundation of China(31902075,32150017 and 32022076).
文摘Geraniol is an important contributor to the pleasant floral scent of tea products and one of the most abundant aroma compounds in tea plants;however,its biosynthesis and physiological function in response to stress in tea plants remain unclear.The proteins encoded by the full-length terpene synthase(CsTPS1)and its alternative splicing isoform(CsTPS1-AS)could catalyze the formation of geraniol when GPP was used as a substrate in vitro,whereas the expression of CsTPS1-AS was only significantly induced by Colletotrichum gloeosporioides and Neopestalotiopsis sp.infection.Silencing of CsTPS1 and CsTPS1-AS resulted in a significant decrease of geraniol content in tea plants.The geraniol content and disease resistance of tea plants were compared when CsTPS1 and CsTPS1-AS were silenced.Down-regulation of the expression of CsTPS1-AS reduced the accumulation of geraniol,and the silenced tea plants exhibited greater susceptibility to pathogen infection than control plants.However,there was no significant difference observed in the geraniol content and pathogen resistance between CsTPS1-silenced plants and control plants in the tea plants infected with two pathogens.Further analysis showed that silencing of CsTPS1-AS led to a decrease in the expression of the defense-related genes PR1 and PR2 and SA pathway-related genes in tea plants,which increased the susceptibility of tea plants to pathogens infections.Both in vitro and in vivo results indicated that CsTPS1 is involved in the regulation of geraniol formation and plant defense via alternative splicing in tea plants.The results of this study provide new insights into geraniol biosynthesis and highlight the role of monoterpene synthases in modulating plant disease resistance via alternative splicing.
文摘Alternative splicing is the process of producing variably spliced mRNAs by choosing distinct combinations of splice sites within a messenger RNA precursor.This splicing enables mRNA from a single gene to synthesize different proteins,which have different cellular properties and functions and yet arise from the same single gene.A family of splicing factors,Serine-arginine rich proteins,are needed to initiate the assembly and activation of the spliceosome.Serine and arginine rich splicing factor 1,part of the arginine/serine-rich splicing factor protein family,can either activate or inhibit the splicing of mRNAs,depending on the phosphorylation status of the protein and its interaction partners.Considering that serine and arginine rich splicing factor 1 is either an activator or an inhibitor,this protein has been studied widely to identify its various roles in different diseases.Research has found that serine and arginine rich splicing factor 1 is a key target for neuroprotection,showing its promising potential use in therapeutics for neurodegenerative disorders.Furthermore,serine and arginine rich splicing factor 1 might be used to regulate cancer development and autoimmune diseases.In this review,we highlight how serine and arginine rich splicing factor 1 has been studied concerning neuroprotection.In addition,we draw attention to how serine and arginine rich splicing factor 1 is being studied in cancer and immunological disorders,as well as how serine and arginine rich splicing factor 1 acts outside the central or peripheral nervous system.
基金supported by the Natural Science Foundation of Shanxi Province(No.20210302124403)the Research Project Supported by Shanxi Scholarship Council of China(No.2021-111)the Science and Technology Innovation Project of Colleges and Universities in Shanxi Province(No.2022L353).
文摘The gradient element of the aperture gradient map is utilized directly to generate the aperture shape without modulation.This process can be likened to choosing the direction of negative gradient descent for the generic aperture shape optimiza-tion.The negative gradient descent direction is more suitable under local conditions and has a slow convergence rate.To overcome these limitations,this study introduced conjugate gradients into aperture shape optimization based on gradient modulation.First,the aperture gradient map of the current beam was obtained for the proposed aperture shape optimiza-tion method,and the gradients of the aperture gradient map were modulated using conjugate gradients to form a modulated gradient map.The aperture shape was generated based on the modulated gradient map.The proposed optimization method does not change the optimal solution of the original optimization problem,but changes the iterative search direction when generating the aperture shape.The performance of the proposed method was verified using cases of head and neck cancer,and prostate cancer.The optimization results indicate that the proposed optimization method better protects the organs at risk and rapidly reduces the objective function value by ensuring a similar dose distribution to the planning target volume.Compared to the contrasting methods,the normal tissue complication probability obtained by the proposed optimization method decreased by up to 4.61%,and the optimization time of the proposed method decreased by 5.26%on average for ten cancer cases.The effectiveness and acceleration of the proposed method were verified through comparative experiments.According to the comparative experiments,the results indicate that the proposed optimization method is more suitable for clinical applications.It is feasible for the aperture shape optimization involving the proposed method.
基金supported by the National Natural Science Foundation of China (31872945 and 31801874)the earmarked fund for China Agricultural Research System (CARS-23-G15)+1 种基金the Funds for Distinguished Young Scientists from Henan Academy of Agricultural Sciences, China (2021JQ03)the Innovation Team of Henan Academy of Agricultural Sciences, China (2021TD06)。
文摘Chinese cabbage is an economically important Brassica vegetable worldwide, and clubroot, which is caused by the soilborne protist plant pathogen Plasmodiophora brassicae is regarded as a destructive disease to Brassica crops. Previous studies on the gene transcripts related to Chinese cabbage resistance to clubroot mainly employed RNA-seq technology,although it cannot provide accurate transcript assembly and structural information. In this study, PacBio RS II SMRT sequencing was used to generate full-length transcriptomes of mixed roots at 0, 2, 5, 8, 13, and 22 days after P. brassicae infection in the clubroot-resistant line DH40R. Overall, 39 376 high-quality isoforms and 26 270 open reading frames(ORFs) were identified from the SMRT sequencing data. Additionally, 426 annotated long noncoding RNAs(lncRNAs),56 transcription factor(TF) families, 1 883 genes with poly(A) sites and 1 691 alternative splicing(AS) events were identified. Furthermore, 1 201 of the genes had at least one AS event in DH40R. A comparison with RNA-seq data revealed six differentially expressed AS genes(one for disease resistance and five for defensive response) that are potentially involved in P. brassicae resistance. The results of this study provide valuable resources for basic research on clubroot resistance in Chinese cabbage.
文摘Main quadrupole magnets are critical for the Circular Electron and Positron Collider(CEPC)and are specifically designed as dual aperture quadrupole(DAQ)magnets.However,the field crosstalk between the two apertures presents challenges.As the CEPC will work at four beam energies of Z,W,Higgs and ttbar mode,the DAQ magnets will operate at four field gradients spanning from 3.18 to 12.63 T/m.The first short quadrupole magnet prototype with the bore diameter of 76 mm and magnetic length of 1.0 m revealed the problems of large magnetic field harmonics and a magnetic center shift within the beam energy range.Accordingly,a compensation method was proposed in this work to solve the field crosstalk effect.By adjusting the gap height at the middle of the two apertures,the field harmonics and magnetic center shift are significantly reduced.After optimization,the short prototype was modified using a new scheme.The field simulations are validated from the magnetic measurement results.Further,the multipole field meets the requirements of the four beam energies.The detailed magnetic field optimization,field harmonics adjustment,and measurement results are presented herein.
文摘Sacred lotus(Nelumbo nucifera)is a typical aquatic plant,belonging to basal eudicot plant,which is ideal for genome and genetic evolutionary study.Understanding lotus gene diversity is important for the study of molecular genetics and breeding.In this research,public RNA-seq data and the annotated reference genome were used to identify the genes in lotus.A total of 26,819 consensus and 1,081 novel genes were identified.Meanwhile,a comprehensive analysis of gene alternative splicing events was conducted,and a total of 19,983“internal”alternative splicing(AS)events and 14,070“complete”AS events were detected in 5,878 and 5,881 multi-exon expression genes,respectively.Observations made from the AS events show the predominance of intron retention(IR)subtype of AS events representing 33%.IR is followed by alternative acceptor(AltA),alternative donor(AltD)and exon skipping(ES),highlighting the universality of the intron definition model in plants.In addition,functional annotations of the gene with AS indicated its relationship to a number of biological processes such as cellular process and metabolic process,showing the key role for alternative splicing in influencing the growth and development of lotus.The results contribute to a better understanding of the current gene diversity in lotus,and provide an abundant resource for future functional genome analysis in lotus.
基金supported by the Natural Science Foundation of Hebei Province (C2021208014)the Key R&D Program of Hebei Province (22326312D, 21326332D)。
文摘In higher plants, the chloroplast is the most important organelle for photosynthesis and for numerous essential metabolic processes in the cell. Although many genes involved in chloroplast development have been identified, the mechanisms underlying such development are not fully understood. In this study, a rice(Oryza sativa) mutant exhibiting pale green color and seedling lethality was isolated from a mutant library. The mutated gene was identified as an ortholog of THA8(thylakoid assembly 8) in Arabidopsis and maize. This gene is designated as OsTHA8 hereafter. OsTHA8 showed a typical pentatricopeptide repeat(PPR) characteristic of only four PPR motifs. Inactivation of OsTHA8 led to a deficiency in chloroplast development in the rice seedling stage. OsTHA8 was expressed mainly in young leaves and leaf sheaths.The OsTHA8 protein was localized to the chloroplast. Loss of function of OsTHA8 weakened the editing efficiency of ndhB-611/737 and rps8-182 transcripts under normal conditions. Y2H and BiFC indicated that OsTHA8 facilitates RNA editing by forming an editosome with multiple organellar RNA editing factor(OsMORF8) and thioredoxin z(OsTRXz), which function in RNA editing in rice chloroplasts. Defective OsTHA8 impaired chloroplast ribosome assembly and resulted in reduced expression of PEP-dependent genes and photosynthesis-related genes. Abnormal splicing of the chloroplast gene ycf3 was detected in ostha8. These findings reveal a synergistic regulatory mechanism of chloroplast biogenesis mediated by RNA, broaden the function of the PPR family, and shed light on the RNA editing complex in rice.
基金supported by National Natural Foundation of China(Grant No.61991454)the project of CAS Interdisciplinary Innovation Team。
文摘High resolution imaging is achieved using increasingly larger apertures and successively shorter wavelengths.Optical aperture synthesis is an important high-resolution imaging technology used in astronomy.Conventional long baseline amplitude interferometry is susceptible to uncontrollable phase fluctuations,and the technical difficulty increases rapidly as the wavelength decreases.The intensity interferometry inspired by HBT experiment is essentially insensitive to phase fluctuations,but suffers from a narrow spectral bandwidth which results in a lack of effective photons.In this study,we propose optical synthetic aperture imaging based on spatial intensity interferometry.This not only realizes diffraction-limited optical aperture synthesis in a single shot,but also enables imaging with a wide spectral bandwidth,which greatly improves the optical energy efficiency of intensity interferometry.And this method is insensitive to the optical path difference between the sub-apertures.Simulations and experiments present optical aperture synthesis diffraction-limited imaging through spatial intensity interferometry in a 100 nm spectral width of visible light,whose maximum optical path difference between the sub-apertures reaches 69λ.This technique is expected to provide a solution for optical aperture synthesis over kilometer-long baselines at optical wavelengths.
基金supported by the National Natural Science Foundation of China(81572563)the National Science Foundations of HUBEI(2018CFB235).
文摘Late-stage ovarian cancer(OC)has a poor prognosis and a high metastasis rate,but the underlying molecular mechanism is unclear.RNA binding proteins(RBPs)play important roles in posttranscriptional regulation in the contexts of neoplasia and tumor metastasis.In this study,we explored the molecular functions of a canonical RBP,Transformer 2βhomolog(TRA2B),in cancer cells.TRA2B knockdown in HeLa cells and subsequent wholetranscriptome RNA sequencing(RNA-seq)analysis revealed the TRA2B-regulated alternative splicing(AS)profile.We disrupted TRA2B expression in epithelial OC cells and performed a series of experiments to confirm the resulting effects on OC cell proliferation,apoptosis and invasion.TRA2B-regulated AS was tightly associated with the mitotic cell cycle,apoptosis and several cancer pathways.Moreover,the expression of hundreds of genes was regulated by TRA2B,and these genes were enriched in the functions of cell proliferation,cell adhesion and angiogenesis,which are related to the malignant phenotype of OC.By integrating the alternatively spliced and differentially expressed genes,we found that AS events and gene expression were regulated independently.We then explored and validated the oncogenic functions of TRA2B by knocking down its expression in OC cells.The high TRA2B expression was associated with poor prognosis in patients with OC.In ovarian tissue,TRA2B expression showed a gradual increasing trend with increasing malignancy.We demonstrated the important roles of TRA2B in ovarian neoplasia and aggressive OC behaviors and identified the underlying molecular mechanisms,facilitating the targeted treatment of OC.
