Background:Alterations in splicing factors contribute to aberrant alternative splicing(AS),which subsequently promotes tumor progression.The splicing factor polypyrimidine tract binding protein 1(PTBP1)has been shown ...Background:Alterations in splicing factors contribute to aberrant alternative splicing(AS),which subsequently promotes tumor progression.The splicing factor polypyrimidine tract binding protein 1(PTBP1)has been shown to facilitate cancer progression by modulating oncogenic variants.However,its specific role and underlying mechanisms in hepatocellular carcinoma(HCC)remain to be elucidated.Methods:PTBP1 expression was evaluated in HCC tissues and cell lines.Subsequently,cells were transfected with vectors designed for PTBP1 overexpression or downregulation.The biological function of PTBP1 was assessed in vitro and in vivo using MTS assays,colony formation assays,transwell assays,xenograft formation,tail vein injection,and orthotopic models.Transcriptome analysis was conducted to elucidate the underlying molecular mechanisms.Results:Our findings demonstrated that PTBP1 exhibited elevated expression in HCC cell lines and tissues.Furthermore,its expression positively correlated with overall and disease-free survival rates,as well as tumor grade and stage.PTBP1 knockdown reduced HCC cell proliferation,migration,and invasion in vitro and suppressed hepatocarcinoma xenograft growth and infiltration in vivo.RNA sequencing(RNA-Seq)analysis identified the AS events associated with PTBP1.PTBP1 functionally enhanced cell proliferation,invasion,and migration by modulating the AS of the microtubule-associated protein tau(MAPT)gene and promoting oncogene expression.Notably,the dysregulation of MAPT splicing coincided with increased PTBP1 expression in HCC.Conclusions:PTBP1-guided AS of the MAPT gene enhances tumorigenicity in HCC through activation of the MAPK/ERK pathways.展开更多
Fiber-optic laser–ultrasound generation is being used in an increasing number of applications, including medical diagnosis, material characterization, and structural health monitoring. However, most currently used fi...Fiber-optic laser–ultrasound generation is being used in an increasing number of applications, including medical diagnosis, material characterization, and structural health monitoring. However, most currently used fiber-optic ultrasonic transducers allow effective ultrasound generation at only a single location, namely, at the fiber tip, although there have been a few limited proposals for achieving multipoint ultrasound generation along the length of a fiber. Here we present a novel fiber-optic ultrasound transducer that uses the core-offset splicing of fibers to effectively generate ultrasound at multiple locations along the fiber. The proposed laser–ultrasonic transducer can produce a balancedstrength signal between ultrasonic generation points by reasonably controlling the offsets of the fibers. The proposed transducer has other outstanding characteristics, including simple fabrication and low cost.展开更多
OCT4 is one of the key transcription factors in maintaining the pluripotency and self-renewal of embryonic stem （ES） cells.Human OCT4 can generate two isoforms OCT4A and OCT4B by alternative splicing.OCT4B1 is a rec...OCT4 is one of the key transcription factors in maintaining the pluripotency and self-renewal of embryonic stem （ES） cells.Human OCT4 can generate two isoforms OCT4A and OCT4B by alternative splicing.OCT4B1 is a recently discovered novel OCT4 spliced variant,which has been considered as a putative marker of stemness.Compared with the OCT4B mRNA,OCT4B1 mRNA is generated by retaining intron 2 as a cryptic exon which contains a TGA stop codon in it.As a result,the protein product of OCT4B1 mRNA could be truncated.Interestingly,we present here that OCT4B1 can indirectly produce the same protein products as OCT4B.We have demonstrated that OCT4B1 mRNA can be spliced into OCT4B mRNA,and encode three protein isoforms.The splicing of OCT4B1 mRNA into OCT4B mRNA can be remarkably inhibited by the mutation of the classical splicing site.Our result suggests that OCT4B mRNA may originate from OCT4B1 mRNA by alternative splicing.展开更多
The shaping form of an untwisted yarn-end for the air splicer is analyzed and then a cosine curve form which will have practically good splicing effect is proposed. The yarn motion in the splicing nozzle by applying h...The shaping form of an untwisted yarn-end for the air splicer is analyzed and then a cosine curve form which will have practically good splicing effect is proposed. The yarn motion in the splicing nozzle by applying hydrodynamics and the splicing principle of the air splicer are also studied.展开更多
RNA splicing normally generates stable splice- junction sequences in viruses that are important in the context of virus mimicry. Potential variability in envelop proteins may occur with point-mutations inducing crypti...RNA splicing normally generates stable splice- junction sequences in viruses that are important in the context of virus mimicry. Potential variability in envelop proteins may occur with point-mutations inducing cryptic splice-junctions, which would remain unrecognized by T-memory cells of higher organisms in vaccine trials. Such aberrant splice- junctions result from evolution-specific non-conser- vation of actual splice-junction sites due to mutations;as such, locations of splice-junctions in a test DNA sequence could only be imprecisely specified. Such impreciseness of splice-junction locations (or cryptic sites) in a sequence is evaluated in this study via “noisy” attributes (with associated stochastics) to the mutated subspace;and, relevant fuzzy considerations are invoked with membership attributes expressed in terms of a spatial signal-to-noise ratio (SSNR). That is, SSNR adopted as a membership function expresses the belongingness of a site-region to exon/intron subspaces. An illustrative example with actual (Dengue 1 viral) DNA data is furnished demonstrating the pursuit developed in predicting aberrant splice-junctions at cryptic sites in the test sequence.展开更多
Pentatricopeptide repeat(PPR)proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression.Here,we report the function of PPR21 in mitochondrial intro...Pentatricopeptide repeat(PPR)proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression.Here,we report the function of PPR21 in mitochondrial intron splicing and its role in maize kernel development.PPR21 is a typical P-type PPR protein targeted to mitochondria.The ppr21 mutants are arrested in embryogenesis and endosperm development,leading to embryo lethality.Null mutations of PPR21 reduce the splicing efficiency of nad2 intron 1,2,and 4 and impair the assembly and activity of mitochondrial complex I.Previous studies show that the P-type PPR protein EMP12 is required for the splicing of identical introns.However,our protein interaction analyses reveal that PPR21 does not interact with EMP12.Instead,both PPR21 and EMP12 interact with the small MutS-related(SMR)domain-containing PPR protein 1(PPR-SMR1)and the short P-type PPR protein 2(SPR2).PPR-SMR1 interacts with SPR2,and both proteins are required for the splicing of many introns in mitochondria,including nad2 intron 1,2,and 4.These results suggest that a PPR21-(PPR-SMR1/SPR2)-EMP12 complex is involved in the splicing of nad2 introns in maize mitochondria.展开更多
In this study,we examine the problem of sliced inverse regression(SIR),a widely used method for sufficient dimension reduction(SDR).It was designed to find reduced-dimensional versions of multivariate predictors by re...In this study,we examine the problem of sliced inverse regression(SIR),a widely used method for sufficient dimension reduction(SDR).It was designed to find reduced-dimensional versions of multivariate predictors by replacing them with a minimally adequate collection of their linear combinations without loss of information.Recently,regularization methods have been proposed in SIR to incorporate a sparse structure of predictors for better interpretability.However,existing methods consider convex relaxation to bypass the sparsity constraint,which may not lead to the best subset,and particularly tends to include irrelevant variables when predictors are correlated.In this study,we approach sparse SIR as a nonconvex optimization problem and directly tackle the sparsity constraint by establishing the optimal conditions and iteratively solving them by means of the splicing technique.Without employing convex relaxation on the sparsity constraint and the orthogonal constraint,our algorithm exhibits superior empirical merits,as evidenced by extensive numerical studies.Computationally,our algorithm is much faster than the relaxed approach for the natural sparse SIR estimator.Statistically,our algorithm surpasses existing methods in terms of accuracy for central subspace estimation and best subset selection and sustains high performance even with correlated predictors.展开更多
目的探讨虚拟仿真结合改良自我导向、问题导向、终身学习、综合临床案例练习(selfdirected,problem-oriented,lifelong learning,integrated clinical case exercise,SPLICE)教学法对临床医学专硕生批判性思维能力的影响。方法选取2024...目的探讨虚拟仿真结合改良自我导向、问题导向、终身学习、综合临床案例练习(selfdirected,problem-oriented,lifelong learning,integrated clinical case exercise,SPLICE)教学法对临床医学专硕生批判性思维能力的影响。方法选取2024年1—6月在锦州医科大学附属第一医院皮肤科进行住院医师规范化培训(简称“住培”)的64名2023级临床医学专硕生为研究对象。采用随机分组法将其分为试验组(n=32)和对照组(n=32)。试验组采用虚拟仿真结合改良SPLICE教学,对照组采用传统教学方式。比较两组学生批判性思维能力、学业自我效能感、理论考核和临床操作技能考核成绩。结果试验组医学专硕生的批判性思维能力、学业自我效能感、理论考核和临床操作技能考核成绩均高于对照组,差异具有统计学意义(均P<0.001)。结论虚拟仿真结合改良SPLICE教学法有助于提升医学专硕生的批判性思维能力与学业自我效能感,有利于其更好地掌握专业理论和临床操作技能,值得在临床教学中进一步推广应用。展开更多
ObjectivesThe PTPRQ gene is essential for preserving the structure and function of stereocilia in inner ear.However,research on splicing mutations within this gene is limited.This study aims to investigate novel splic...ObjectivesThe PTPRQ gene is essential for preserving the structure and function of stereocilia in inner ear.However,research on splicing mutations within this gene is limited.This study aims to investigate novel splicing mutations in PTPRQ,clarify their molecular mechanisms,and provide new insights into the genetic factors associated with hearing loss,ultimately enhancing diagnostic accuracy.MethodClinical data and peripheral blood samples were obtained from members of a family with congenital hearing loss.Variants were identified through high-throughput sequencing and confirmed by Sanger sequencing to ensure genealogical co-segregation.The splicing effects of PTPRQ variants were evaluated using bioinformatics tools and minigene assays.ResultsWe used whole exome sequencing to identify novel double compound heterozygous splice-altering variants(c.5426+1 G>A and c.6603-3 T>G)in the PTPRQ gene with DFNB84A.We molecularly characterized these variants,and they were found to co-segregate with the disease within the family.Minigene assays and Sanger sequencing confirmed that the c.6603-3 T>G variant caused exon 43 skipping,resulting in a frameshift mutation(p.Ser2201ArgfsTer112).Further bioinformatic analysis supported these findings.ConclusionsThis study identifies a novel compound heterozygous splicing variant in the PTPRQ gene in a Chinese family with DFNB84A,expanding the known spectrum of PTPRQ mutations.These findings enhance the understanding of PTPRQ-related hearing loss and may aid in early diagnosis,prevention,and therapeutic strategies.展开更多
Caspases,which play key roles in cell apoptosis,undergo alternative splicing to form different splicing variants that can regulate the apoptotic process.Lepidopteran insect caspases undergo alternative splicing,althou...Caspases,which play key roles in cell apoptosis,undergo alternative splicing to form different splicing variants that can regulate the apoptotic process.Lepidopteran insect caspases undergo alternative splicing,although the functions of their splicing variants are still unclear.The Spodoptera exigua caspase-5(SeCaspase-5)gene was cloned and found to produce four different splicing variants with different gene sequences and protein functional domains,which were named SeCaspase-5a,SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Overexpression of these variants in S.exigua cells(Se-3)showed that SeCaspase-5a had a proapoptotic function,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not.Semi-qPCR analysis revealed that the expression of the SeCaspase-5 variants significantly differed during Autographa californica multiple nucleopolyhedrovirus(AcMNPV)infection.Furthermore,the SeCaspase-5 variants were constructed into the AcMNPV bacmid and transfected into Se-3 cells,which revealed that SeCaspase-5a promoted cell apoptosis and reduced virus production,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not promote cell apoptosis but instead increased virus production.Moreover,an analysis of the interactions between the SeCaspase-5 variants revealed that SeCaspase-5a directly interacted with SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Coexpression of these variants in Se-3 cells also revealed that SeCaspase-5b,SeCaspase-5c and SeCaspase-5d inhibited the proapoptotic function of SeCaspase-5a,resulting in a reduction in the percentage of apoptotic cells by about 20%.These results indicate that SeCaspase-5 undergoes alternative splicing and is involved in regulating the apoptosis induced by baculovirus infection.These findings increase our understanding of the functions of lepidopteran insect caspases and provide new insights into the mechanism of host-cell apoptosis induced by baculoviruses.展开更多
The formation of root system architecture(RSA)plays a crucial role in plant growth.OsDRO1 is known to have a function in controlling RSA in rice,however,the role of potato StDRO2,a homolog of rice OsDRO1,in root growt...The formation of root system architecture(RSA)plays a crucial role in plant growth.OsDRO1 is known to have a function in controlling RSA in rice,however,the role of potato StDRO2,a homolog of rice OsDRO1,in root growth remains unclear.In this study,we obtained potato dro2 mutant lines by Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-Associated 9(CRISPR/Cas9)-mediated genome editing system.The mutant lines were generated from a splicing defect of the StDRO2 intron 1,which causes a nonsense mutation in StDRO2.Furthermore,the secondary structure of StDRO2 mRNA analyzed with RNAfold Web Server was altered in the dro2 mutant.Mutation of StDRO2 conveys potato adaptation through changing the RSA via alteration of auxin transport under drought stress.The potato dro2 lines showed higher plant height,longer root length,smaller root growth angle and increased tuber weight than the wild-type.The alteration of RSA was associated with a disturbance of IAA distribution in the dro2 mutant,and the levels of StPIN7 and StPIN10 detected by using real-time PCR were up-regulated in the roots of potato dro2 lines grown under drought stress.Moreover,the microRNAs(miRNAs)PmiREN024536 and PmiREN024486 targeted the StDRO2 gene,and auxin positively and negatively regulated the expression of StDRO2 and the miRNAs PmiREN024536 and PmiREN024486,respectively,in the potato roots.Our data shows that a regulatory network involving auxin,StDRO2,PmiREN024536 and PmiREN024486 can control RSA to convey potato fitness under drought stress.展开更多
Heat stress is a major threat to maize(Zea mays L.)production worldwide.Heat shock transcription factors(HSFs)play vital roles in plant responses to heat stress.However,the molecular and genetic mechanisms underlying ...Heat stress is a major threat to maize(Zea mays L.)production worldwide.Heat shock transcription factors(HSFs)play vital roles in plant responses to heat stress.However,the molecular and genetic mechanisms underlying HSF-meditated thermotolerance in maize remain largely unexplored.In this study,we demonstrate that the alternative splicing of ZmHsf23 modulates heat stress tolerance in maize.Hsf23 produced two functional transcripts,Hsf23L and Hsf23S,which differ by the presence of a cryptic mini-exon in Hsf23L that is spliced out in Hsf23S.Both transcripts were strongly induced by heat stress.Mutants lacking Hsf23L alone(hsf23l)or both Hsf23L and Hsf23S(hsf23l23s)exhibited increased susceptibility to heat stress,whereas overexpression of Hsf23S enhanced heat stress tolerance in maize.Subsequently,we found that Hsf23S positively regulates heat stress tolerance by directly activating the transcription of three sHSP genes(Hsp16.9,Hsp17.2,and Hsp18a)and TIL1 gene.In addition,Hsf23L physically interacted with Hsf23S and enhanced the transcriptional activation of Hsf23S on the sHSPs and TIL1 promoters.Notably,genetic analysis suggested that co-overexpression of Hsf23L and Hsf23S further improves heat tolerance of the transgenic plants.Taken together,these results reveal two splicing variants of ZmHsf23 cooperatively regulate maize heat tolerance,thus highlighting potential value of ZmHsf23 in breeding heat-tolerant maize varieties.展开更多
Background:Glioblastoma(GBM)is one of the most malignant types of central nervous system tumors.Oxygen deprivation in the tumor microenvironment is thought to be an important factor in promoting GBM progression.Howeve...Background:Glioblastoma(GBM)is one of the most malignant types of central nervous system tumors.Oxygen deprivation in the tumor microenvironment is thought to be an important factor in promoting GBM progression.However,the mechanisms of hypoxia-promoted tumor progression remain elusive.Methods:Alternative splicing of diacylglycerol kinase gamma(DGKG)-Δexon13 was amplified and verified by PCR-Sanger sequencing.The functions of DGKG and DGKG-Δexon13 were analyzed by Cell counting kit-8(CCK-8),Transwell,Matrigeltranswell experiments,and in vivo orthotropic GBM animal models.Transcriptome analyses were done to find out the regulated genes.Results:In this study,we found that a new transcript DGKG-Δexon13 was generated in GBM under hypoxia via alternative splicing.Moreover,the results of CCK-8,Transwell,and Matrigel-transwell experiments showed that the proliferation,migration,and invasion abilities of U87-MG and T98G were decreased after DGKG knockdown.Compared to wild-type DGKG,DGKG-Δexon13 overexpression significantly promoted cellular proliferation,migration,and invasion abilities in GBM.Furthermore,in vivo,orthotropic GBM animal models analysis showed that the tumor volumes were much smaller in the DGKG knockdown group.However,the tumor sizes in the DGKG and DGKG-Δexon13 rescue groups were restored,especially in the DGKG-Δexon13 group.Transcriptome analysis revealed that MORC1,KLHDC7B,ATP1A2,INHBE,TMEM119,and FGD3 were altered significantly when DGKG was knocked down.IL-16,CCN2,and EFNB3 were specifically regulated by DGKG-Δexon13.Conclusions:Our study found that hypoxia-induced alternative splicing transcript DGKG-Δexon13 promotes GBM proliferation and infiltration,which might provide a new potential target for the clinical treatment and diagnosis of GBM.展开更多
Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synt...Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.展开更多
Myocardial infarction(MI)is characterized by focal necrosis resulting from prolonged myocardial ischemia due to coronary artery obstruction.Vascular reconstruction following MI is crucial for improving cardiac functio...Myocardial infarction(MI)is characterized by focal necrosis resulting from prolonged myocardial ischemia due to coronary artery obstruction.Vascular reconstruction following MI is crucial for improving cardiac function and preventing recurrent infarction.This study investigates the interaction between macrophages and endothelial cells in angiogenesis mediated by nicotinamide mononucleotide(NMN)-induced secretion of macrophage-derived exosomes.We focus on the role of U2 small nuclear RNA auxiliary factor 1(U2af1)gene,a member of the splicing factor serine and arginine(SR)gene family,in the regulation of angiogenesis.Through cardiac ultrasound,Masson staining,2,3,5-triphenyltetrazolium chloride(TTC)staining,Microfil vascular perfusion,and platelet and endothelial cell adhesion molecule 1(CD31)immunofluorescence staining,extracellular vesicles from NMN-stimulated macrophages were shown to exert a protective effect in MI,with proteomic analysis identifying U2AF1 as a candidate protein involved in MI protection.Plasma U2AF1 levels were measured in 70 MI patients,revealing significantly lower levels in individuals with poor coronary collateral vessel(CCV;Rentrop scores 0–1)than in those with good CCV(Rentrop scores 2–3).In both myocardial and hindlimb ischemia mouse models,overexpression of endothelial cell-specific adenoviral overexpression U2AF1 promoted angiogenesis in the heart and hindlimbs and improved cardiac function after MI.Mechanistic studies demonstrated that U2AF1 regulates the alternative splicing(AS)of Yes1-associated transcriptional regulator(Yap1)gene,influencing post-MI angiogenesis and cardiac function recovery.Collectively,our clinical findings suggest that U2AF1 may serve as a therapeutic target for coronary collateral angiogenesis following MI.Given the low immunogenicity and high biosafety of exosomes,this study provides a foundational basis and translational potential for exosome-based therapies in MI treatment.展开更多
Ser/Arg-rich （SR） genes encode proteins that play pivotal roles in both constitutive and alternative splicing of pre-mRNA. However, not much effort has been made to investigate the alternative splicing of their own ...Ser/Arg-rich （SR） genes encode proteins that play pivotal roles in both constitutive and alternative splicing of pre-mRNA. However, not much effort has been made to investigate the alternative splicing of their own pre-mRNA. In this study, we conducted comprehensive analyses of pre-mRNA splicing for 22 SR genes in three rice （Oryza sativa L.） ecotypes indica, japonica andjavanica. Using different ecotypes we characterized the variations in expression and splicing patterns of rice SR genes in different tissues and at different developmental stages. In addition, we compared the divergence in expression and splicing patterns of SR genes from seedlings of different rice ecotypes in response to hormones application and environmental stresses. Our results revealed the complexity of alternative splicing of SR genes in rice. The splicing varies in different tissues, in different ecotypes, in response to stresses and hormones. Thus, our study suggested that SR genes were subjected to sophisticated alternative splicing although their encoding proteins were involved in the splicing process.展开更多
The neuronal microtubule-associated protein tau is abnormally hyperphosphorylated and aggregated into neurofibrillary tangles in the brains of individuals with Alzheimer＇s disease and related neurodegenerative disord...The neuronal microtubule-associated protein tau is abnormally hyperphosphorylated and aggregated into neurofibrillary tangles in the brains of individuals with Alzheimer＇s disease and related neurodegenerative disorders. The adult human brain expresses six isoforms of tau generated by alternative splicing of exons 2, 3, and 10 of its pre-mRNA. Exon 10 encodes the second microtubule-binding repeat of tau. Its alternative splicing produces tau isoforms with either three or four microtubule-binding repeats, termed 3R-tau and 4R- tau. In the normal adult human brain, the level of 3R-tau is approximately equal to that of 4R-tau. Several silent and intronic mutations of the tau gene associated with FTDP-17T （frontotemporal dementia with Parkinsonism linked to chromosome 17 and specifically characterized by tau pathology） only disrupt exon 10 splicing, but do not influence the primary sequence of the tau protein. Thus, abnormal exon 10 splicing is sufficient to cause neurodegeneration and dementia. Here, we review the regulation of tau exon 10 splicing by cis-elements and trans-factors and summarize all the mutations associated with FTDP-17T and related tauopathies. The findings suggest that correction of exon 10 splicing may be a potential target for tau exon 10 splicing-related tauopathies.展开更多
基金supported by the National Natural Science Foundation of China(Nos.81972771,82173062)the Key Areas Project of Education Department of Guangdong Province(No.2021ZDZX2017)+3 种基金the Tertiary Education Scientific Research Project of Guangzhou Municipal Education Bureau(No.202235387)the Guangzhou Science and Technology Project of Guangzhou Municipal Science and Technology Bureau(No.2023A03J0428)the Natural Science Foundation of Guangdong Province,China(No.2024A1515013082)the Guangdong Basic and Applied Basic Research 21 Foundation(No.2021A1515010403).
文摘Background:Alterations in splicing factors contribute to aberrant alternative splicing(AS),which subsequently promotes tumor progression.The splicing factor polypyrimidine tract binding protein 1(PTBP1)has been shown to facilitate cancer progression by modulating oncogenic variants.However,its specific role and underlying mechanisms in hepatocellular carcinoma(HCC)remain to be elucidated.Methods:PTBP1 expression was evaluated in HCC tissues and cell lines.Subsequently,cells were transfected with vectors designed for PTBP1 overexpression or downregulation.The biological function of PTBP1 was assessed in vitro and in vivo using MTS assays,colony formation assays,transwell assays,xenograft formation,tail vein injection,and orthotopic models.Transcriptome analysis was conducted to elucidate the underlying molecular mechanisms.Results:Our findings demonstrated that PTBP1 exhibited elevated expression in HCC cell lines and tissues.Furthermore,its expression positively correlated with overall and disease-free survival rates,as well as tumor grade and stage.PTBP1 knockdown reduced HCC cell proliferation,migration,and invasion in vitro and suppressed hepatocarcinoma xenograft growth and infiltration in vivo.RNA sequencing(RNA-Seq)analysis identified the AS events associated with PTBP1.PTBP1 functionally enhanced cell proliferation,invasion,and migration by modulating the AS of the microtubule-associated protein tau(MAPT)gene and promoting oncogene expression.Notably,the dysregulation of MAPT splicing coincided with increased PTBP1 expression in HCC.Conclusions:PTBP1-guided AS of the MAPT gene enhances tumorigenicity in HCC through activation of the MAPK/ERK pathways.
基金National Natural Science Foundation of China(NSFC)(61575051,61675055)Shenzhen Municipal Science and Technology Plan Project(JCYJ20150529114045265,JSGG2015 0529153336124,KQCX20140521144416706)
文摘Fiber-optic laser–ultrasound generation is being used in an increasing number of applications, including medical diagnosis, material characterization, and structural health monitoring. However, most currently used fiber-optic ultrasonic transducers allow effective ultrasound generation at only a single location, namely, at the fiber tip, although there have been a few limited proposals for achieving multipoint ultrasound generation along the length of a fiber. Here we present a novel fiber-optic ultrasound transducer that uses the core-offset splicing of fibers to effectively generate ultrasound at multiple locations along the fiber. The proposed laser–ultrasonic transducer can produce a balancedstrength signal between ultrasonic generation points by reasonably controlling the offsets of the fibers. The proposed transducer has other outstanding characteristics, including simple fabrication and low cost.
基金supported by the National Basic Research Program of China (973 Program) (No 2006CB943601)the National Natural Science Foundation of China (NSFC) (No 90919042)
文摘OCT4 is one of the key transcription factors in maintaining the pluripotency and self-renewal of embryonic stem （ES） cells.Human OCT4 can generate two isoforms OCT4A and OCT4B by alternative splicing.OCT4B1 is a recently discovered novel OCT4 spliced variant,which has been considered as a putative marker of stemness.Compared with the OCT4B mRNA,OCT4B1 mRNA is generated by retaining intron 2 as a cryptic exon which contains a TGA stop codon in it.As a result,the protein product of OCT4B1 mRNA could be truncated.Interestingly,we present here that OCT4B1 can indirectly produce the same protein products as OCT4B.We have demonstrated that OCT4B1 mRNA can be spliced into OCT4B mRNA,and encode three protein isoforms.The splicing of OCT4B1 mRNA into OCT4B mRNA can be remarkably inhibited by the mutation of the classical splicing site.Our result suggests that OCT4B mRNA may originate from OCT4B1 mRNA by alternative splicing.
文摘The shaping form of an untwisted yarn-end for the air splicer is analyzed and then a cosine curve form which will have practically good splicing effect is proposed. The yarn motion in the splicing nozzle by applying hydrodynamics and the splicing principle of the air splicer are also studied.
文摘RNA splicing normally generates stable splice- junction sequences in viruses that are important in the context of virus mimicry. Potential variability in envelop proteins may occur with point-mutations inducing cryptic splice-junctions, which would remain unrecognized by T-memory cells of higher organisms in vaccine trials. Such aberrant splice- junctions result from evolution-specific non-conser- vation of actual splice-junction sites due to mutations;as such, locations of splice-junctions in a test DNA sequence could only be imprecisely specified. Such impreciseness of splice-junction locations (or cryptic sites) in a sequence is evaluated in this study via “noisy” attributes (with associated stochastics) to the mutated subspace;and, relevant fuzzy considerations are invoked with membership attributes expressed in terms of a spatial signal-to-noise ratio (SSNR). That is, SSNR adopted as a membership function expresses the belongingness of a site-region to exon/intron subspaces. An illustrative example with actual (Dengue 1 viral) DNA data is furnished demonstrating the pursuit developed in predicting aberrant splice-junctions at cryptic sites in the test sequence.
基金supported by the National Natural Science Foundation of China(32072126 and 32230075)the Shandong Provincial Natural Science Foundation(ZR2019MC005).
文摘Pentatricopeptide repeat(PPR)proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression.Here,we report the function of PPR21 in mitochondrial intron splicing and its role in maize kernel development.PPR21 is a typical P-type PPR protein targeted to mitochondria.The ppr21 mutants are arrested in embryogenesis and endosperm development,leading to embryo lethality.Null mutations of PPR21 reduce the splicing efficiency of nad2 intron 1,2,and 4 and impair the assembly and activity of mitochondrial complex I.Previous studies show that the P-type PPR protein EMP12 is required for the splicing of identical introns.However,our protein interaction analyses reveal that PPR21 does not interact with EMP12.Instead,both PPR21 and EMP12 interact with the small MutS-related(SMR)domain-containing PPR protein 1(PPR-SMR1)and the short P-type PPR protein 2(SPR2).PPR-SMR1 interacts with SPR2,and both proteins are required for the splicing of many introns in mitochondria,including nad2 intron 1,2,and 4.These results suggest that a PPR21-(PPR-SMR1/SPR2)-EMP12 complex is involved in the splicing of nad2 introns in maize mitochondria.
文摘In this study,we examine the problem of sliced inverse regression(SIR),a widely used method for sufficient dimension reduction(SDR).It was designed to find reduced-dimensional versions of multivariate predictors by replacing them with a minimally adequate collection of their linear combinations without loss of information.Recently,regularization methods have been proposed in SIR to incorporate a sparse structure of predictors for better interpretability.However,existing methods consider convex relaxation to bypass the sparsity constraint,which may not lead to the best subset,and particularly tends to include irrelevant variables when predictors are correlated.In this study,we approach sparse SIR as a nonconvex optimization problem and directly tackle the sparsity constraint by establishing the optimal conditions and iteratively solving them by means of the splicing technique.Without employing convex relaxation on the sparsity constraint and the orthogonal constraint,our algorithm exhibits superior empirical merits,as evidenced by extensive numerical studies.Computationally,our algorithm is much faster than the relaxed approach for the natural sparse SIR estimator.Statistically,our algorithm surpasses existing methods in terms of accuracy for central subspace estimation and best subset selection and sustains high performance even with correlated predictors.
文摘目的探讨虚拟仿真结合改良自我导向、问题导向、终身学习、综合临床案例练习(selfdirected,problem-oriented,lifelong learning,integrated clinical case exercise,SPLICE)教学法对临床医学专硕生批判性思维能力的影响。方法选取2024年1—6月在锦州医科大学附属第一医院皮肤科进行住院医师规范化培训(简称“住培”)的64名2023级临床医学专硕生为研究对象。采用随机分组法将其分为试验组(n=32)和对照组(n=32)。试验组采用虚拟仿真结合改良SPLICE教学,对照组采用传统教学方式。比较两组学生批判性思维能力、学业自我效能感、理论考核和临床操作技能考核成绩。结果试验组医学专硕生的批判性思维能力、学业自我效能感、理论考核和临床操作技能考核成绩均高于对照组,差异具有统计学意义(均P<0.001)。结论虚拟仿真结合改良SPLICE教学法有助于提升医学专硕生的批判性思维能力与学业自我效能感,有利于其更好地掌握专业理论和临床操作技能,值得在临床教学中进一步推广应用。
基金supported in part by the Natural Science Foundation of Shandong Province(no.ZR2022QH373,ZR2022QH292 and ZR2023MH2474).
文摘ObjectivesThe PTPRQ gene is essential for preserving the structure and function of stereocilia in inner ear.However,research on splicing mutations within this gene is limited.This study aims to investigate novel splicing mutations in PTPRQ,clarify their molecular mechanisms,and provide new insights into the genetic factors associated with hearing loss,ultimately enhancing diagnostic accuracy.MethodClinical data and peripheral blood samples were obtained from members of a family with congenital hearing loss.Variants were identified through high-throughput sequencing and confirmed by Sanger sequencing to ensure genealogical co-segregation.The splicing effects of PTPRQ variants were evaluated using bioinformatics tools and minigene assays.ResultsWe used whole exome sequencing to identify novel double compound heterozygous splice-altering variants(c.5426+1 G>A and c.6603-3 T>G)in the PTPRQ gene with DFNB84A.We molecularly characterized these variants,and they were found to co-segregate with the disease within the family.Minigene assays and Sanger sequencing confirmed that the c.6603-3 T>G variant caused exon 43 skipping,resulting in a frameshift mutation(p.Ser2201ArgfsTer112).Further bioinformatic analysis supported these findings.ConclusionsThis study identifies a novel compound heterozygous splicing variant in the PTPRQ gene in a Chinese family with DFNB84A,expanding the known spectrum of PTPRQ mutations.These findings enhance the understanding of PTPRQ-related hearing loss and may aid in early diagnosis,prevention,and therapeutic strategies.
基金funded by the National Natural Science Foundation of China(32202393)the Natural Science Foundation of Shandong Province,China(ZR2021QC190)+1 种基金the Science and Technology Benefiting the People Demonstration Project of Qingdao,China(24-1-8-xdny-10-nsh)the Qingdao Agricultural University High-level Talent Fund,China(663/1120101)。
文摘Caspases,which play key roles in cell apoptosis,undergo alternative splicing to form different splicing variants that can regulate the apoptotic process.Lepidopteran insect caspases undergo alternative splicing,although the functions of their splicing variants are still unclear.The Spodoptera exigua caspase-5(SeCaspase-5)gene was cloned and found to produce four different splicing variants with different gene sequences and protein functional domains,which were named SeCaspase-5a,SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Overexpression of these variants in S.exigua cells(Se-3)showed that SeCaspase-5a had a proapoptotic function,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not.Semi-qPCR analysis revealed that the expression of the SeCaspase-5 variants significantly differed during Autographa californica multiple nucleopolyhedrovirus(AcMNPV)infection.Furthermore,the SeCaspase-5 variants were constructed into the AcMNPV bacmid and transfected into Se-3 cells,which revealed that SeCaspase-5a promoted cell apoptosis and reduced virus production,whereas SeCaspase-5b,SeCaspase-5c and SeCaspase-5d did not promote cell apoptosis but instead increased virus production.Moreover,an analysis of the interactions between the SeCaspase-5 variants revealed that SeCaspase-5a directly interacted with SeCaspase-5b,SeCaspase-5c and SeCaspase-5d.Coexpression of these variants in Se-3 cells also revealed that SeCaspase-5b,SeCaspase-5c and SeCaspase-5d inhibited the proapoptotic function of SeCaspase-5a,resulting in a reduction in the percentage of apoptotic cells by about 20%.These results indicate that SeCaspase-5 undergoes alternative splicing and is involved in regulating the apoptosis induced by baculovirus infection.These findings increase our understanding of the functions of lepidopteran insect caspases and provide new insights into the mechanism of host-cell apoptosis induced by baculoviruses.
基金supported by grants from the National Natural Science Foundation of China(Grant Nos.32260085,31860064,31660501,31970609,32260718 and 31901870)the Key Projects of the Applied Basic Research Plan of Yunnan Province(Grant No.202301AS070082)+3 种基金the Start-up fund from Xishuangbanna Tropical Botanical Garden,the‘Top Talents Program in Science and Technology’from Yunnan Province,the Major Science and Technology Project in Yunnan Province(Grant Nos.202102AE090042 and 202202AE090036)the Young and Middle-Aged Academic and Technical Leaders Reserve Talent Program in Yunnan Province(Grant No.202205AC160076)China Postdoctoral Science Foundation(Grant No.2019M653849XB)the High-level Talents Introduction Plan of Yunnan Province-Young Talents Special Project。
文摘The formation of root system architecture(RSA)plays a crucial role in plant growth.OsDRO1 is known to have a function in controlling RSA in rice,however,the role of potato StDRO2,a homolog of rice OsDRO1,in root growth remains unclear.In this study,we obtained potato dro2 mutant lines by Clustered Regularly Interspaced Short Palindromic Repeats-CRISPR-Associated 9(CRISPR/Cas9)-mediated genome editing system.The mutant lines were generated from a splicing defect of the StDRO2 intron 1,which causes a nonsense mutation in StDRO2.Furthermore,the secondary structure of StDRO2 mRNA analyzed with RNAfold Web Server was altered in the dro2 mutant.Mutation of StDRO2 conveys potato adaptation through changing the RSA via alteration of auxin transport under drought stress.The potato dro2 lines showed higher plant height,longer root length,smaller root growth angle and increased tuber weight than the wild-type.The alteration of RSA was associated with a disturbance of IAA distribution in the dro2 mutant,and the levels of StPIN7 and StPIN10 detected by using real-time PCR were up-regulated in the roots of potato dro2 lines grown under drought stress.Moreover,the microRNAs(miRNAs)PmiREN024536 and PmiREN024486 targeted the StDRO2 gene,and auxin positively and negatively regulated the expression of StDRO2 and the miRNAs PmiREN024536 and PmiREN024486,respectively,in the potato roots.Our data shows that a regulatory network involving auxin,StDRO2,PmiREN024536 and PmiREN024486 can control RSA to convey potato fitness under drought stress.
基金supported by the National Key Research and Development Program of China(2021YFF1000301)the National Natural Science Foundation of China(31771805)。
文摘Heat stress is a major threat to maize(Zea mays L.)production worldwide.Heat shock transcription factors(HSFs)play vital roles in plant responses to heat stress.However,the molecular and genetic mechanisms underlying HSF-meditated thermotolerance in maize remain largely unexplored.In this study,we demonstrate that the alternative splicing of ZmHsf23 modulates heat stress tolerance in maize.Hsf23 produced two functional transcripts,Hsf23L and Hsf23S,which differ by the presence of a cryptic mini-exon in Hsf23L that is spliced out in Hsf23S.Both transcripts were strongly induced by heat stress.Mutants lacking Hsf23L alone(hsf23l)or both Hsf23L and Hsf23S(hsf23l23s)exhibited increased susceptibility to heat stress,whereas overexpression of Hsf23S enhanced heat stress tolerance in maize.Subsequently,we found that Hsf23S positively regulates heat stress tolerance by directly activating the transcription of three sHSP genes(Hsp16.9,Hsp17.2,and Hsp18a)and TIL1 gene.In addition,Hsf23L physically interacted with Hsf23S and enhanced the transcriptional activation of Hsf23S on the sHSPs and TIL1 promoters.Notably,genetic analysis suggested that co-overexpression of Hsf23L and Hsf23S further improves heat tolerance of the transgenic plants.Taken together,these results reveal two splicing variants of ZmHsf23 cooperatively regulate maize heat tolerance,thus highlighting potential value of ZmHsf23 in breeding heat-tolerant maize varieties.
基金funded by Guizhou Province Science and Technology Plan Project Qiankehe Foundation-ZK[2023]General 360,362Science and Technology Fund project of Guizhou Provincial Health Commission(gzwkj-2022-09,gzwkj-2023-035)+1 种基金National Natural Science Foundation Cultivation Project of Guizhou Medical University(21NSFCP14,gyfynsfc-2022-25)The PhD Scientific Research Launch Fund Project of the Affiliated Hospital of Guizhou Medical University(gyfybsky-2022-02).
文摘Background:Glioblastoma(GBM)is one of the most malignant types of central nervous system tumors.Oxygen deprivation in the tumor microenvironment is thought to be an important factor in promoting GBM progression.However,the mechanisms of hypoxia-promoted tumor progression remain elusive.Methods:Alternative splicing of diacylglycerol kinase gamma(DGKG)-Δexon13 was amplified and verified by PCR-Sanger sequencing.The functions of DGKG and DGKG-Δexon13 were analyzed by Cell counting kit-8(CCK-8),Transwell,Matrigeltranswell experiments,and in vivo orthotropic GBM animal models.Transcriptome analyses were done to find out the regulated genes.Results:In this study,we found that a new transcript DGKG-Δexon13 was generated in GBM under hypoxia via alternative splicing.Moreover,the results of CCK-8,Transwell,and Matrigel-transwell experiments showed that the proliferation,migration,and invasion abilities of U87-MG and T98G were decreased after DGKG knockdown.Compared to wild-type DGKG,DGKG-Δexon13 overexpression significantly promoted cellular proliferation,migration,and invasion abilities in GBM.Furthermore,in vivo,orthotropic GBM animal models analysis showed that the tumor volumes were much smaller in the DGKG knockdown group.However,the tumor sizes in the DGKG and DGKG-Δexon13 rescue groups were restored,especially in the DGKG-Δexon13 group.Transcriptome analysis revealed that MORC1,KLHDC7B,ATP1A2,INHBE,TMEM119,and FGD3 were altered significantly when DGKG was knocked down.IL-16,CCN2,and EFNB3 were specifically regulated by DGKG-Δexon13.Conclusions:Our study found that hypoxia-induced alternative splicing transcript DGKG-Δexon13 promotes GBM proliferation and infiltration,which might provide a new potential target for the clinical treatment and diagnosis of GBM.
基金supported by the Major Program of National Agricultural Science and Technology of China(NK20220607)the Sichuan Science and Technology Program,China(2023YFH0041)。
文摘Starch biosynthesis is a complex process that relies on the coordinated action of multiple enzymes.Resistant starch is not digested in the small intestine,thus preventing a rapid rise in the glycemic index.Starch synthase 2a(SS2a)is a key enzyme in amylopectin biosynthesis that has significant effects on starch structure and properties.In this study,we identified an ss2a null mutant(M3-1413)with a single base mutation from an ethyl methane sulfonate(EMS)-mutagenized population of barley.The mutation was located at the 3'end of the first intron of the RNA splicing receptor(AG)site,and resulted in abnormal RNA splicing and two abnormal transcripts of ss2a,which caused the inactivation of the SS2a gene.The starch structure and properties were significantly altered in the mutant,with M3-1413 containing lower total starch and higher amylose and resistant starch levels.This study sheds light on the effect of barley ss2a null mutations on starch properties and will help to guide new applications of barley starch in the development of nutritious food products.
基金supported by the National Natural Science Founda-tion of China(82370417,82330011,and U21A20339)the Science Fund for Distinguished Young Scholars of Heilongjiang Province(JQ2024H001)the Heilongjiang Provincial Postdoctoral Science Foundation(LBH-Z23212).
文摘Myocardial infarction(MI)is characterized by focal necrosis resulting from prolonged myocardial ischemia due to coronary artery obstruction.Vascular reconstruction following MI is crucial for improving cardiac function and preventing recurrent infarction.This study investigates the interaction between macrophages and endothelial cells in angiogenesis mediated by nicotinamide mononucleotide(NMN)-induced secretion of macrophage-derived exosomes.We focus on the role of U2 small nuclear RNA auxiliary factor 1(U2af1)gene,a member of the splicing factor serine and arginine(SR)gene family,in the regulation of angiogenesis.Through cardiac ultrasound,Masson staining,2,3,5-triphenyltetrazolium chloride(TTC)staining,Microfil vascular perfusion,and platelet and endothelial cell adhesion molecule 1(CD31)immunofluorescence staining,extracellular vesicles from NMN-stimulated macrophages were shown to exert a protective effect in MI,with proteomic analysis identifying U2AF1 as a candidate protein involved in MI protection.Plasma U2AF1 levels were measured in 70 MI patients,revealing significantly lower levels in individuals with poor coronary collateral vessel(CCV;Rentrop scores 0–1)than in those with good CCV(Rentrop scores 2–3).In both myocardial and hindlimb ischemia mouse models,overexpression of endothelial cell-specific adenoviral overexpression U2AF1 promoted angiogenesis in the heart and hindlimbs and improved cardiac function after MI.Mechanistic studies demonstrated that U2AF1 regulates the alternative splicing(AS)of Yes1-associated transcriptional regulator(Yap1)gene,influencing post-MI angiogenesis and cardiac function recovery.Collectively,our clinical findings suggest that U2AF1 may serve as a therapeutic target for coronary collateral angiogenesis following MI.Given the low immunogenicity and high biosafety of exosomes,this study provides a foundational basis and translational potential for exosome-based therapies in MI treatment.
基金supported by the National Basic Research Program of China (2011CB100401)the National Science Fund of China for Distinguished Young Scientists(30825030)+1 种基金the National Natural Science Foundation of China (30970260,30770466 and 30971752)the Key Project from Chongqing Local Government,China(2010AA1019)
文摘Ser/Arg-rich （SR） genes encode proteins that play pivotal roles in both constitutive and alternative splicing of pre-mRNA. However, not much effort has been made to investigate the alternative splicing of their own pre-mRNA. In this study, we conducted comprehensive analyses of pre-mRNA splicing for 22 SR genes in three rice （Oryza sativa L.） ecotypes indica, japonica andjavanica. Using different ecotypes we characterized the variations in expression and splicing patterns of rice SR genes in different tissues and at different developmental stages. In addition, we compared the divergence in expression and splicing patterns of SR genes from seedlings of different rice ecotypes in response to hormones application and environmental stresses. Our results revealed the complexity of alternative splicing of SR genes in rice. The splicing varies in different tissues, in different ecotypes, in response to stresses and hormones. Thus, our study suggested that SR genes were subjected to sophisticated alternative splicing although their encoding proteins were involved in the splicing process.
基金supported by Nantong UniversityNew York State Institute for Basic Research in Developmental Disabilities+3 种基金by grants from the National Natural Science Foundation of China(81030059 and 81170317)the Basic Research Program of Education Department of Jiangsu Province,China(10KJA310040)the U.S.Alzheimer’s Association(Grant IIRG-10-173154)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)of China
文摘The neuronal microtubule-associated protein tau is abnormally hyperphosphorylated and aggregated into neurofibrillary tangles in the brains of individuals with Alzheimer＇s disease and related neurodegenerative disorders. The adult human brain expresses six isoforms of tau generated by alternative splicing of exons 2, 3, and 10 of its pre-mRNA. Exon 10 encodes the second microtubule-binding repeat of tau. Its alternative splicing produces tau isoforms with either three or four microtubule-binding repeats, termed 3R-tau and 4R- tau. In the normal adult human brain, the level of 3R-tau is approximately equal to that of 4R-tau. Several silent and intronic mutations of the tau gene associated with FTDP-17T （frontotemporal dementia with Parkinsonism linked to chromosome 17 and specifically characterized by tau pathology） only disrupt exon 10 splicing, but do not influence the primary sequence of the tau protein. Thus, abnormal exon 10 splicing is sufficient to cause neurodegeneration and dementia. Here, we review the regulation of tau exon 10 splicing by cis-elements and trans-factors and summarize all the mutations associated with FTDP-17T and related tauopathies. The findings suggest that correction of exon 10 splicing may be a potential target for tau exon 10 splicing-related tauopathies.
