Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in viv...Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause CMT2.Mutations located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)model.In addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive control.Of these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut allele.We found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in Drosophila.Flies heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal morphology.These Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.展开更多
The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest re...The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest resistance needs to be considered.Here,we first investigate RNAi-based biopesticide resistance of Fusarium asiaticum,which is responsible for devastating diseases of plants,for example,Fusarium head blight.Five resistant strains were isolated from 500 strains that treated with UV-mutagenesis.The mutation common to all of the five resistant mutants occurred in the gene encoding Dicer2(point mutations at codon 1005 and 1007),which were under strong purifying selection pressure.To confirm whether the mutations in Dicer2 confer resistance to RNAi,we exchanged the Dicer2 locus between the sensitive strain and the resistant strain by homologous double exchange.The transformed mutants,Dicer2^(R1005D)and Dicer2^(E1007H),exhibited resistance to dsRNA in vitro.Further study showed that mutations of R1005D and E1007H affected the intramolecular interactions of Dicer2,resulting in the dysfunction of RNase III domain of Dicer2.The amount of sRNAs produced by Dicer2^(R1005D)and Dicer2^(E1007H)was extremely reduced along with variation of sRNA length.Together,these findings revealed a new potential mechanism of RNAi resistance and provided insight into RNAi-related biopesticide deployment for fungal control.展开更多
BACKGROUND Pancreatic cancer(PC)is a highly malignant tumor that is resistant to chemotherapy,radiotherapy and immunotherapy.Combination chemotherapy regimens are the standard first-line regimens for metastatic diseas...BACKGROUND Pancreatic cancer(PC)is a highly malignant tumor that is resistant to chemotherapy,radiotherapy and immunotherapy.Combination chemotherapy regimens are the standard first-line regimens for metastatic disease,with a median survival<12 months.Although recurrent genomic alterations such as the BRAF V600E mutation have been reported in PC,evidence supporting the clinical effectiveness of molecularly guided targeted therapies is limited.CASE SUMMARY We report a case of a 33-year-old male who was referred to our department with weight loss of 5 kg in 2 months,anorexia and abdominal pain.Imaging showed extensive lesions involving the pancreas,liver,bones,muscles and lymph nodes accompanied by elevated carbohydrate antigen 19-9(CA19-9)and carcinoembryonic antigen(CEA).Biopsy yielded a diagnosis of PC.Treatment with gemcitabine and nab-paclitaxel was initiated,but the disease progressed in<2 months even though the patient’s general condition improved.Molecular testing revealed the presence of BRAF mutation.Dabrafenib/trametinib combination therapy was introduced,and the patient was treated for 2 months with a decrease in CA19-9 and CEA levels,but he died after 2 months of treatment.CONCLUSION BRAF alterations are infrequent in PC.This case highlights the significance of molecular profiling in patients with PC,especially in patients with a high tumor burden.展开更多
To the editor:In a recent article published in Pediatric Investigation,Zhang et al.reported a case series of phacomatosis pigmentovascularis(PPV).1 Among such cases,one was described as featuring an extensive laterali...To the editor:In a recent article published in Pediatric Investigation,Zhang et al.reported a case series of phacomatosis pigmentovascularis(PPV).1 Among such cases,one was described as featuring an extensive lateralized telangiectatic nevus,a large hypermelanotic patch and a Klippel-Trenaunay phenotype;and another an extensive lateralised telangiectatic nevus,a nevus anemicus,an extensive nevus cesius,a large hypermelanotic patch and a Sturge-Weber-Klippel-Trenaunay phenotype.1 These cases were diagnosed as unclassifiable PPV and phacomatosis cesioflammea;instead,their clinical features are compatible with phacomatosis melanorosea(PMR)and phacomatosis melanocesioflammea(PMCF),respectively.展开更多
BACKGROUND The aim of this study was to investigate the complex heterozygous mutations of ANK1 and SPTA1 in the same individual and improve our understanding of hereditary spherocytosis(HS)in children.We also hope to ...BACKGROUND The aim of this study was to investigate the complex heterozygous mutations of ANK1 and SPTA1 in the same individual and improve our understanding of hereditary spherocytosis(HS)in children.We also hope to promote the application of gene detection technology in children with HS,with the goals of identifying more related gene mutations,supporting the acquisition of improved molecular genetic information to further reveal the pathogenesis of HS in children,and providing important guidance for the diagnosis,treatment,and prevention of HS in children.CASE SUMMARY A 1-year and 5-month-old patient presented jaundice during the neonatal period,mild anemia 8 months later,splenic enlargement at 1 year and 5 months,and brittle red blood cell permeability.Genetic testing was performed on the patient,their parents,and sister.Swiss Model software was used to predict the protein structure of complex heterozygous mutations in ANK1 and SPTA1.Genetic testing revealed that the patient harbored a new mutation in the ANK1 gene from the father and a mutation in the SPTA1 gene from the mother.Combined with the clinical symptoms of the children,it is suggested that the newly discovered complex heterozygous mutations of ANK1 and SPTA1 may be the cause,providing important guidance for revealing the pathogenesis,diagnosis,treatment,and promotion of gene detection technology in children with HS.CONCLUSION This case involves an unreported complex heterozygous mutation of ANK1 and SPTA1,which provides a reference for exploring HS.展开更多
Owing to significantly prolonged survival,targeted therapy has become standardized recommendation for advanced non-small cell lung cancer patients with mutated driver genes.However,the genetic status of lung cancer pa...Owing to significantly prolonged survival,targeted therapy has become standardized recommendation for advanced non-small cell lung cancer patients with mutated driver genes.However,the genetic status of lung cancer patients is dynamic.By dynamically monitoring the evolution of genes status,differential genes and concomitant genes related to progressive disease could be confirmed early,so as to achieve a more accurate and comprehensive insight of the whole process management of targeted therapy for lung cancer patients.Under the guidance of accurate genetic testing results,it is helpful to provide patients with more effective,long-term,and stable individualized targeted therapy.展开更多
In Senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of gene...In Senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of genetic predisposition. The sequencing of the human genome, which has led to the discovery of millions of sequence variations, makes it possible to study variations within sequences. These variations are limited to Single Nucleotide Polymorphisms (SNPs) and this common form of polymorphism occurs approximately every 1000 bases in the human genome and 1.8 million SNPs are currently listed according to [1]. The aim of this study is to gain a better understanding of the impact of mutations in the D-loop region of mtDNA on ovarian cancer in Senegalese women. This study involved searching for mutations in our study population after DNA extraction and sequencing. Mutations were found after a comparison of our sequences with the Cambridge reference sequence (NC_012920). The mutations found in the DNA studied extend from position 7 to position 16568 and most of these mutations are located in the hypervariate zones (HV1 and HV2). Heteroplasmy with three mutant alleles was also found in certain variants. Common mutations were found in both healthy and cancerous tissues, with almost identical frequencies in both types of tissue. This enabled us to understand the spread of tumor cells throughout the ovary.展开更多
Objective:This study investigated the clinical significance of DICER1 mutations in patients with distant metastatic follicular cell-derived thyroid cancer(FDTC).Methods:This study included 310 Chinese patients with di...Objective:This study investigated the clinical significance of DICER1 mutations in patients with distant metastatic follicular cell-derived thyroid cancer(FDTC).Methods:This study included 310 Chinese patients with distant metastatic FDTC.We analyzed the interactions between DICER1 mutations and other gene alterations and compared the clinicopathological characteristics of patients with pathogenic(P)or likely pathogenic(LP)DICER1 mutations(n=9),other gene alterations(n=253),and no gene alterations(n=37).To compare FDTCs with different drivers,isolated BRAFV600E,RAS mutations,and RET fusions were compared with isolated DICER1 mutations.Results:The prevalence of DICER1 mutations was 6.5%(20/310)in the patient cohort.Among patients with DICER1 mutations,45%(9/20)harbored P or LP DICER1 variants and 55%(11/20)harbored DICER1 variants of uncertain significance(VUS).The coexistence of DICER1 mutations and other gene alterations was detected in65%(13/20)of patients.Compared with VUS,P or LP DICER1 variants were almost mutually exclusive with early driver alterations(such as BRAFV600E)(11.1%vs.81.8%,P=0.002)and more coexisted with late-hit events,particularly TP53 mutations(44.4%vs.27.3%,P=0.642).Clinically,compared with the no alteration and other alteration groups,the DICER1 mutation group exhibited larger primary tumors,higher poorly differentiated thyroid cancer proportion,more extrathyroidal extension,more extrapulmonary metastases,and higher radioactive iodine-refractory proportion(all P<0.05).Cases with isolated DICER1 mutations differed from those with isolated BRAFV600E and RET fusions in terms of tumor size,poorly differentiated thyroid cancer proportion,and metastatic sites,but were similar to cases with isolated RAS mutations in the high proportion of follicular thyroid cancer,N0,and extrapulmonary metastases.Conclusions:Mutation of DICER1 gene is a non-negligible molecular event and it may represent an aggressive subset of FDTCs.DICER1 has RAS-like clinical characteristics and DICER1-mutant tumors exhibit more aggressive clinical behaviors compared with those with BRAFV600E and RET fusions.展开更多
Background:Strong sex disparities have been observed among patients with bladder cancer(BCa).FGFR3 is one of the most frequently mutated genes in bladder cancer,and there are inconsistencies in its frequency in male a...Background:Strong sex disparities have been observed among patients with bladder cancer(BCa).FGFR3 is one of the most frequently mutated genes in bladder cancer,and there are inconsistencies in its frequency in male and female patients.Methods:Here,we conducted a meta-analysis comparing the FGFR3 somatic mutation frequency in men and women among 7351 patients with BCa from 18 cohorts.Results:We showed that female patients had a 1.32 times higher risk of having FGFR3 somatic mutations than males.This difference was attributed to mutations occurring at the 2 most frequently mutated sites,S249 and Y375.Additionally,nonsense mutations were more likely to be found in women,whereas indel/frameshift mutations were almost exclusively found in men;however,no difference was noted for missense mutations.Conclusions:A female sex bias in FGFR3 somatic mutationswas observed in BCa.Well-powered individual participant data analyses addressing the possible confounding effects of other factors(eg,age,ethnicity,smoking status,muscle invasiveness,and molecular subtype),as well as analyses integrating omics and functional investigations,are warranted to further validate and explain the mechanisms of the current findings.展开更多
Background: Methylmalonate semialdehyde dehydrogenase(ALDH6A1), encoded by the ALDH6A1 gene, is essential for the metabolic degradation of valine and thymine.Genetic alterations in ALDH6A1 lead to methylmalonate semia...Background: Methylmalonate semialdehyde dehydrogenase(ALDH6A1), encoded by the ALDH6A1 gene, is essential for the metabolic degradation of valine and thymine.Genetic alterations in ALDH6A1 lead to methylmalonate semialdehyde dehydrogenase deficiency(MMSDD), a rare disease with only five reported disease mutations, focusing on its molecular foundation but lacking in-depth mechanistic investigations. Therefore, the structural and biochemical properties of the ALDH6A1mutants have not yet been thoroughly examined.Methods: Wild-type(WT) and mutant ALDH6A1 were constructed as plasmids and purified after prokaryotic expression to obtain conformationally homogeneous and pure protein. The structures of ALDH6A1 mutants(P62S, Y172H & R535C, S262Y,P421S, and G446R) were solved using cryo-electron microscopy. Based on the results of ALDH6A1 WT, enzyme activity and thermal stability experiments of their mutants were performed to explore the ALDH6A1's biochemical characteristics.Results: This study presents a structural analysis of the ALDH6A1 mutants, P62S,Y172H & R535C, S262Y, P421S, and G446R at resolutions of 3.70, 2.92, 3.12, 3.47,and 3.00 Å, respectively. However, the electronic density of ALDH6A1 P421S is poor,and it is difficult to fit into this density. Furthermore, the root-mean-square deviation(r.m.s.d.) of ALDH6A1 WT with these mutants was significant. This study revealed a tetrameric structure with closely interacting monomers, except for ALDH6A1 P62S,which forms a dimer, and is consistent with the principles of the aldehyde dehydrogenase family. Moreover, these disease mutations also affect enzyme activity and thermal stability.Conclusions: Our findings shed light on disease mutations that contribute to the properties of ALDH6A1 and lead to the genesis of MMSDD from structural and biochemical perspectives, which holds promise as a potential theoretical basis for this rare disease.展开更多
BACKGROUND The SETD1B gene is instrumental in human intelligence and nerve development.Mutations in the SETD1B gene have been linked in recent studies to neurodevelopmental disorders,seizures,and language delay.CASE S...BACKGROUND The SETD1B gene is instrumental in human intelligence and nerve development.Mutations in the SETD1B gene have been linked in recent studies to neurodevelopmental disorders,seizures,and language delay.CASE SUMMARY This study aimed to analyze the clinical manifestations and treatment of three patients suffering from mental retardation,epilepsy,and language delay resulting from a new mutation in the SETD1B gene.Three individuals with these symptoms were selected,and their clinical symptoms,gene test results,and treatment were analyzed.This article discusses the impact of the SETD1B gene mutation on patients and outlines the treatment approach.Among the three patients(two females and one male,aged 8,4,and 1,respectively),all exhibited psychomotor retardation,attention deficit,and hyperactivity disorder,and two had epilepsy.Antiepileptic treatment with sodium tripolyvalproate halted the seizures in the affected child,although mental development remained somewhat delayed.Whole exome sequencing revealed new mutations in the SETD1B gene for all patients,specifically with c.5473C>T(p.Arg1825trp),c.4120C>T(p.Gln1374*,593),c.14_15insC(p.His5Hisfs*33).CONCLUSION Possessing the SETD1B gene mutation may cause mental retardation accompanied by seizures and language delay.Although the exact mechanism is not fully understood,interventions such as drug therapy,rehabilitation training,and family support can assist patients in managing their symptoms and enhancing their quality of life.Furthermore,genetic testing supplies healthcare providers with more precise diagnostic and therapeutic guidance,informs families about genetic disease risks,and contributes to understanding disease pathogenesis and drug research and development.展开更多
Genome sequencing has revealed frequent mutations in Ras homolog family member A(RHOA)among various cancers with unique aberrant profiles and pathogenic effects,especially in peripheral T-cell lymphoma(PTCL).The discr...Genome sequencing has revealed frequent mutations in Ras homolog family member A(RHOA)among various cancers with unique aberrant profiles and pathogenic effects,especially in peripheral T-cell lymphoma(PTCL).The discrete positional distribution and types of RHOA amino acid substitutions vary according to the tumor type,thereby leading to different functional and biological properties,which provide new insight into the molecular pathogenesis and potential targeted therapies for various tumors.However,the similarities and discrepancies in characteristics of RHOA mutations among various histologic subtypes of PTCL have not been fully elucidated.Herein we highlight the inconsistencies and complexities of the type and location of RHOA mutations and demonstrate the contribution of RHOA variants to the pathogenesis of PTCL by combining epigenetic abnormalities and activating multiple downstream pathways.The promising potential of targeting RHOA as a therapeutic modality is also outlined.This review provides new insight in the field of personalized medicine to improve the clinical outcomes for patients.展开更多
Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of sm...Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive tumors.However,the role of GNAS mutations in the invasiveness of GHPAs is unclear.GNAS mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing procedure.The expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with RT-qPCR.MEG3 was manipulated in GH3 cells using a lentiviral expression system.Cell invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western blotting.Finally,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and invasiveness.The invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type GNAS.Consistently,the invasiveness of mutant GNASexpressing GH3 cells decreased.MEG3 is uniquely expressed at high levels in GHPAs harboring mutated GNAS.Accordingly,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell invasion.Mechanistically,GNAS mutations inhibit EMT in GHPAs.MEG3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in vivo.Our data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway.展开更多
Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primar...Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development.展开更多
Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic stability.However,our study of the wild-type Streptococcus pneumoniae D39,a pathogen resp...Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic stability.However,our study of the wild-type Streptococcus pneumoniae D39,a pathogen responsible for many common diseases,revealed a high spontaneous mutation rate of 0.02 per genome per cell division in mutation-accumulation(MA)lines.This rate is orders of magnitude higher than that of other non-mutator bacteria and is characterized by a high mutation bias in the A/T direction.The high mutation rate may have resulted from a reduction in the overall efficiency of selection,conferred by the tiny effective population size in nature.In line with this,S.pneumoniae D39 also exhibited the lowest DNA mismatch-repair(MMR)efficiency among bacteria.Treatment with the antibiotic penicillin did not elevate the mutation rate,as penicillin did not induce DNA damage and S.pneumoniae lacks a stress response pathway.Our findings suggested that the MA results are applicable to within-host scenarios and provide insights into pathogen evolution.展开更多
BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing f...BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing factors in Chinese patients have not been thoroughly described.AIM To analyze the clinicopathological features of KRAS,NRAS,BRAF,and PIK3CA mutations and the DNA MMR status in CRC.METHODS We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital.MMR proteins were tested using immunohistochemical analysis,and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction.Microsatellite status was determined using an MSI detection kit.Statistical analyses were conducted using SPSS software and logistic regression.RESULTS The KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 44.6%,3.4%,3.7%,and 3.9% of CRC patients,respectively.KRAS mutations were more likely to occur in patients with moderate-to-high differentiation.BRAF mutations were more likely to occur in patients with right-sided CRC,poorly differentiated,or no perineural invasion.Deficient MMR(dMMR)was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas.KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 29.6%,1.1%,8.1%,and 22.3% of patients with dMMR,respectively.The dMMR was more likely to occur in patients with a family history of CRC,aged<50 years,right-sided CRC,poorly differentiated histology,no perineural invasion,and with carcinoma in situ,stage I,or stage II tumors.CONCLUSION This study analyzed the molecular profiles of KRAS,NRAS,BRAF,PIK3CA,and MMR/MSI in CRC,identifying key influencing factors,with implications for clinical management of CRC.展开更多
Objective： To investigate the association between the mutations in lipoprotein lipase gene and hypertriglyceridemia （HTG）. Methods： The lipoprotein lipase （LPL） gene was screened for mutations in 386 Chinese sub...Objective： To investigate the association between the mutations in lipoprotein lipase gene and hypertriglyceridemia （HTG）. Methods： The lipoprotein lipase （LPL） gene was screened for mutations in 386 Chinese subjects with （108 cases in the HTG group） or without HTG （278 cases in the control group）, by single-strand conformation polymorphism （SSCP） analysis and DNA sequencing. Results： One novel silent mutation L103L, one missense mutation P207L, three splicing mutations Int3/3＇ -ass/C（-6）→T, and the common S447X polymorphism has been identified in the whole coding region and exon-intron junctions of the LPL gene were examined. Heterozygous P207L found in the HTG group was the first case reported in Asia and subsequently another P207L heterozygote was found in the proband＇s family, all of which suggested that P207L was one of the causes of familial combined hyperlipidemia, but was not so prevalent as that in French Canadian. Int3/3＇-ass/C（-6）→T was found in both groups in the present study although it was regarded as a pathogenic variant to HTG earlier on. Moreover about the beneficial polymorphism S447X, there was also some supportive evidence that the levels of triglycerides （TG） in S447X carriers were significantly lower than noncarders in the subjects without HTG. Conclusions： The association between the LPL variants and HTG is quite complicated and versatile, genotyping of LPL in a larger-scale screening should be necessary and justifiable.展开更多
BACKGROUND Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1(APPL1)plays a crucial role in regulating insulin signaling and glucose metabolism.Mutations in the APPL1 gene have been associ...BACKGROUND Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1(APPL1)plays a crucial role in regulating insulin signaling and glucose metabolism.Mutations in the APPL1 gene have been associated with the development of maturity-onset diabetes of the young type 14(MODY14).Currently,only two mutations[c.1655T>A(p.Leu552*)and c.281G>A p.(Asp94Asn)]have been identified in association with this disease.Given the limited understanding of MODY14,it is imperative to identify additional cases and carry out comprehensive research on MODY14 and APPL1 mutations.AIM To assess the pathogenicity of APPL1 gene mutations in diabetic patients and to characterize the functional role of the APPL1 domain.METHODS Patients exhibiting clinical signs and a medical history suggestive of MODY were screened for the study.Whole exome sequencing was performed on the patients as well as their family members.The pathogenicity of the identified APPL1 variants was predicted on the basis of bioinformatics analysis.In addition,the pathogenicity of the novel APPL1 variant was preliminarily evaluated through in vitro functional experiments.Finally,the impact of these variants on APPL1 protein expression and the insulin pathway were assessed,and the potential mechanism underlying the interaction between the APPL1 protein and the insulin receptor was further explored.RESULTS A total of five novel mutations were identified,including four missense mutations(Asp632Tyr,Arg633His,Arg532Gln,and Ile642Met)and one intronic mutation(1153-16A>T).Pathogenicity prediction analysis revealed that the Arg532Gln was pathogenic across all predictions.The Asp632Tyr and Arg633His variants also had pathogenicity based on MutationTaster.In addition,multiple alignment of amino acid sequences showed that the Arg532Gln,Asp632Tyr,and Arg633His variants were conserved across different species.Moreover,in in vitro functional experiments,both the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were found to downregulate the expression of APPL1 on both protein and mRNA levels,indicating their pathogenic nature.Therefore,based on the patient’s clinical and family history,combined with the results from bioinformatics analysis and functional experiment,the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were classified as pathogenic mutations.Importantly,all these mutations were located within the phosphotyrosinebinding domain of APPL1,which plays a critical role in the insulin sensitization effect.CONCLUSION This study provided new insights into the pathogenicity of APPL1 gene mutations in diabetes and revealed a potential target for the diagnosis and treatment of the disease.展开更多
The severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)belongs to the genus Beta coronavirus and the family of Coronaviridae.It is a positive-sense,non-segmented single-strand RNA virus.Four common types of hu...The severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)belongs to the genus Beta coronavirus and the family of Coronaviridae.It is a positive-sense,non-segmented single-strand RNA virus.Four common types of human coronaviruses circulate globally,particularly in the fall and winter seasons.They are responsible for 10%-30% of all mild upper respiratory tract infections in adults.These are 229E,NL63 of the Alfacoronaviridae family,OC43,and HKU1 of the Betacoronaviridae family.However,there are three highly pathogenic human coronaviruses:SARS-CoV-2,Middle East respiratory syndrome coronavirus,and the latest pandemic caused by the SARS-CoV-2 infection.All viruses,including SARS-CoV-2,have the inherent tendency to evolve.SARS-CoV-2 is still evolving in humans.Additionally,due to the development of herd immunity,prior infection,use of medication,vaccination,and antibodies,the viruses are facing immune pressure.During the replication process and due to immune pressure,the virus may undergo mutations.Several SARS-CoV-2 variants,including the variants of concern(VOCs),such as B.1.1.7(Alpha),B.1.351(Beta),B.1.617/B.1.617.2(Delta),P.1(Gamma),and B.1.1.529(Omicron)have been reported from various parts of the world.These VOCs contain several important mutations;some of them are on the spike proteins.These mutations may lead to enhanced infectivity,transmissibility,and decreased neutralization efficacy by monoclonal antibodies,convalescent sera,or vaccines.Mutations may also lead to a failure of detection by molecular diagnostic tests,leading to a delayed diagnosis,increased community spread,and delayed treatment.We searched PubMed,EMBASE,Covariant,the Stanford variant Database,and the CINAHL from December 2019 to February 2023 using the following search terms:VOC,SARS-CoV-2,Omicron,mutations in SARS-CoV-2,etc.This review discusses the various mutations and their impact on infectivity,transmissibility,and neutralization efficacy.展开更多
In recent years, there has been a global rise in cases of papillary thyroid carcinoma (PTC), the predominant form of thyroid cancer. Advances in molecular biology have intensified the focus on the genetic mutations as...In recent years, there has been a global rise in cases of papillary thyroid carcinoma (PTC), the predominant form of thyroid cancer. Advances in molecular biology have intensified the focus on the genetic mutations associated with this malignancy. Researchers have conducted extensive investigations into these mutations to elucidate their roles in the initiation, progression, treatment, and prognosis of PTC. This review synthesizes studies on the genetic mutations implicated in PTC, examining specific mutated genes, mechanisms of mutation, correlations with clinicopathological features, and their influence on treatment outcomes and prognosis. The objective is to provide a theoretical framework for enhancing the diagnosis, treatment, and prognostic assessment of PTC in the future.展开更多
基金supported by the Natural Science Foundation of Fujian Province,No.2020J02027the National Natural Science Foundation of China,No.31970461the Foundation of NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate,Fujian Maternity and Child Health Hospital,No.2022-NHP-05(all to WC).
文摘Certain amino acids changes in the human Na^(+)/K^(+)-ATPase pump,ATPase Na^(+)/K^(+)transporting subunit alpha 1(ATP1A1),cause Charcot-Marie-Tooth disease type 2(CMT2)disease and refractory seizures.To develop in vivo models to study the role of Na^(+)/K^(+)-ATPase in these diseases,we modified the Drosophila gene homolog,Atpα,to mimic the human ATP1A1 gene mutations that cause CMT2.Mutations located within the helical linker region of human ATP1A1(I592T,A597T,P600T,and D601F)were simultaneously introduced into endogenous Drosophila Atpαby CRISPR/Cas9-mediated genome editing,generating the Atpα^(TTTF)model.In addition,the same strategy was used to generate the corresponding single point mutations in flies(Atpα^(I571T),Atpα^(A576T),Atpα^(P579T),and Atpα^(D580F)).Moreover,a deletion mutation(Atpα^(mut))that causes premature termination of translation was generated as a positive control.Of these alleles,we found two that could be maintained as homozygotes(Atpα^(I571T)and Atpα^(P579T)).Three alleles(Atpα^(A576T),Atpα^(P579)and Atpα^(D580F))can form heterozygotes with the Atpαmut allele.We found that the Atpαallele carrying these CMT2-associated mutations showed differential phenotypes in Drosophila.Flies heterozygous for Atpα^(TTTF)mutations have motor performance defects,a reduced lifespan,seizures,and an abnormal neuronal morphology.These Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.
基金funded by the National Natural Science Foundation of China(32372585)the Natural Science Foundation of Jiangsu Province,China(BK20231471)the National Training Program of Innovation and Entrepreneurship for Undergraduates,China(202210307013Z)。
文摘The use of RNA interference(RNAi)technology to control pests is explored by researchers globally.Even though RNA is a new class of pest control compound unlike conventional chemical pesticides,the evolution of pest resistance needs to be considered.Here,we first investigate RNAi-based biopesticide resistance of Fusarium asiaticum,which is responsible for devastating diseases of plants,for example,Fusarium head blight.Five resistant strains were isolated from 500 strains that treated with UV-mutagenesis.The mutation common to all of the five resistant mutants occurred in the gene encoding Dicer2(point mutations at codon 1005 and 1007),which were under strong purifying selection pressure.To confirm whether the mutations in Dicer2 confer resistance to RNAi,we exchanged the Dicer2 locus between the sensitive strain and the resistant strain by homologous double exchange.The transformed mutants,Dicer2^(R1005D)and Dicer2^(E1007H),exhibited resistance to dsRNA in vitro.Further study showed that mutations of R1005D and E1007H affected the intramolecular interactions of Dicer2,resulting in the dysfunction of RNase III domain of Dicer2.The amount of sRNAs produced by Dicer2^(R1005D)and Dicer2^(E1007H)was extremely reduced along with variation of sRNA length.Together,these findings revealed a new potential mechanism of RNAi resistance and provided insight into RNAi-related biopesticide deployment for fungal control.
基金Supported by Clinical Research Center for Precision Medicine of Abdominal Tumor of Fujian Province.
文摘BACKGROUND Pancreatic cancer(PC)is a highly malignant tumor that is resistant to chemotherapy,radiotherapy and immunotherapy.Combination chemotherapy regimens are the standard first-line regimens for metastatic disease,with a median survival<12 months.Although recurrent genomic alterations such as the BRAF V600E mutation have been reported in PC,evidence supporting the clinical effectiveness of molecularly guided targeted therapies is limited.CASE SUMMARY We report a case of a 33-year-old male who was referred to our department with weight loss of 5 kg in 2 months,anorexia and abdominal pain.Imaging showed extensive lesions involving the pancreas,liver,bones,muscles and lymph nodes accompanied by elevated carbohydrate antigen 19-9(CA19-9)and carcinoembryonic antigen(CEA).Biopsy yielded a diagnosis of PC.Treatment with gemcitabine and nab-paclitaxel was initiated,but the disease progressed in<2 months even though the patient’s general condition improved.Molecular testing revealed the presence of BRAF mutation.Dabrafenib/trametinib combination therapy was introduced,and the patient was treated for 2 months with a decrease in CA19-9 and CEA levels,but he died after 2 months of treatment.CONCLUSION BRAF alterations are infrequent in PC.This case highlights the significance of molecular profiling in patients with PC,especially in patients with a high tumor burden.
文摘To the editor:In a recent article published in Pediatric Investigation,Zhang et al.reported a case series of phacomatosis pigmentovascularis(PPV).1 Among such cases,one was described as featuring an extensive lateralized telangiectatic nevus,a large hypermelanotic patch and a Klippel-Trenaunay phenotype;and another an extensive lateralised telangiectatic nevus,a nevus anemicus,an extensive nevus cesius,a large hypermelanotic patch and a Sturge-Weber-Klippel-Trenaunay phenotype.1 These cases were diagnosed as unclassifiable PPV and phacomatosis cesioflammea;instead,their clinical features are compatible with phacomatosis melanorosea(PMR)and phacomatosis melanocesioflammea(PMCF),respectively.
基金Supported by The Science and Technology Department of Sichuan Province,No.2021JDKP0015.
文摘BACKGROUND The aim of this study was to investigate the complex heterozygous mutations of ANK1 and SPTA1 in the same individual and improve our understanding of hereditary spherocytosis(HS)in children.We also hope to promote the application of gene detection technology in children with HS,with the goals of identifying more related gene mutations,supporting the acquisition of improved molecular genetic information to further reveal the pathogenesis of HS in children,and providing important guidance for the diagnosis,treatment,and prevention of HS in children.CASE SUMMARY A 1-year and 5-month-old patient presented jaundice during the neonatal period,mild anemia 8 months later,splenic enlargement at 1 year and 5 months,and brittle red blood cell permeability.Genetic testing was performed on the patient,their parents,and sister.Swiss Model software was used to predict the protein structure of complex heterozygous mutations in ANK1 and SPTA1.Genetic testing revealed that the patient harbored a new mutation in the ANK1 gene from the father and a mutation in the SPTA1 gene from the mother.Combined with the clinical symptoms of the children,it is suggested that the newly discovered complex heterozygous mutations of ANK1 and SPTA1 may be the cause,providing important guidance for revealing the pathogenesis,diagnosis,treatment,and promotion of gene detection technology in children with HS.CONCLUSION This case involves an unreported complex heterozygous mutation of ANK1 and SPTA1,which provides a reference for exploring HS.
基金National Natural Science Foundation of China(No.81873396)Capital Health Development Research Project(No.2018-2-4065)Project of China-Japan Friendship Hospital(No.2018-HX-26)。
文摘Owing to significantly prolonged survival,targeted therapy has become standardized recommendation for advanced non-small cell lung cancer patients with mutated driver genes.However,the genetic status of lung cancer patients is dynamic.By dynamically monitoring the evolution of genes status,differential genes and concomitant genes related to progressive disease could be confirmed early,so as to achieve a more accurate and comprehensive insight of the whole process management of targeted therapy for lung cancer patients.Under the guidance of accurate genetic testing results,it is helpful to provide patients with more effective,long-term,and stable individualized targeted therapy.
文摘In Senegal in particular, ovarian cancer, which is one of the most common gynecological cancers, accounts for 2.8% of deaths. The most important risk factor is genetic, with 10% of cases occurring in a context of genetic predisposition. The sequencing of the human genome, which has led to the discovery of millions of sequence variations, makes it possible to study variations within sequences. These variations are limited to Single Nucleotide Polymorphisms (SNPs) and this common form of polymorphism occurs approximately every 1000 bases in the human genome and 1.8 million SNPs are currently listed according to [1]. The aim of this study is to gain a better understanding of the impact of mutations in the D-loop region of mtDNA on ovarian cancer in Senegalese women. This study involved searching for mutations in our study population after DNA extraction and sequencing. Mutations were found after a comparison of our sequences with the Cambridge reference sequence (NC_012920). The mutations found in the DNA studied extend from position 7 to position 16568 and most of these mutations are located in the hypervariate zones (HV1 and HV2). Heteroplasmy with three mutant alleles was also found in certain variants. Common mutations were found in both healthy and cancerous tissues, with almost identical frequencies in both types of tissue. This enabled us to understand the spread of tumor cells throughout the ovary.
基金supported by the National High Level Hospital Clinical Research Funding(No.2022-PUMCHB-072)。
文摘Objective:This study investigated the clinical significance of DICER1 mutations in patients with distant metastatic follicular cell-derived thyroid cancer(FDTC).Methods:This study included 310 Chinese patients with distant metastatic FDTC.We analyzed the interactions between DICER1 mutations and other gene alterations and compared the clinicopathological characteristics of patients with pathogenic(P)or likely pathogenic(LP)DICER1 mutations(n=9),other gene alterations(n=253),and no gene alterations(n=37).To compare FDTCs with different drivers,isolated BRAFV600E,RAS mutations,and RET fusions were compared with isolated DICER1 mutations.Results:The prevalence of DICER1 mutations was 6.5%(20/310)in the patient cohort.Among patients with DICER1 mutations,45%(9/20)harbored P or LP DICER1 variants and 55%(11/20)harbored DICER1 variants of uncertain significance(VUS).The coexistence of DICER1 mutations and other gene alterations was detected in65%(13/20)of patients.Compared with VUS,P or LP DICER1 variants were almost mutually exclusive with early driver alterations(such as BRAFV600E)(11.1%vs.81.8%,P=0.002)and more coexisted with late-hit events,particularly TP53 mutations(44.4%vs.27.3%,P=0.642).Clinically,compared with the no alteration and other alteration groups,the DICER1 mutation group exhibited larger primary tumors,higher poorly differentiated thyroid cancer proportion,more extrathyroidal extension,more extrapulmonary metastases,and higher radioactive iodine-refractory proportion(all P<0.05).Cases with isolated DICER1 mutations differed from those with isolated BRAFV600E and RET fusions in terms of tumor size,poorly differentiated thyroid cancer proportion,and metastatic sites,but were similar to cases with isolated RAS mutations in the high proportion of follicular thyroid cancer,N0,and extrapulmonary metastases.Conclusions:Mutation of DICER1 gene is a non-negligible molecular event and it may represent an aggressive subset of FDTCs.DICER1 has RAS-like clinical characteristics and DICER1-mutant tumors exhibit more aggressive clinical behaviors compared with those with BRAFV600E and RET fusions.
基金Supported by the National Natural Science Foundation of China(no.82303057)Natural Science Foundation of Hubei Province of China(no.2023AFB521)“Chutian Scholars Program”of Hubei Province of China.
文摘Background:Strong sex disparities have been observed among patients with bladder cancer(BCa).FGFR3 is one of the most frequently mutated genes in bladder cancer,and there are inconsistencies in its frequency in male and female patients.Methods:Here,we conducted a meta-analysis comparing the FGFR3 somatic mutation frequency in men and women among 7351 patients with BCa from 18 cohorts.Results:We showed that female patients had a 1.32 times higher risk of having FGFR3 somatic mutations than males.This difference was attributed to mutations occurring at the 2 most frequently mutated sites,S249 and Y375.Additionally,nonsense mutations were more likely to be found in women,whereas indel/frameshift mutations were almost exclusively found in men;however,no difference was noted for missense mutations.Conclusions:A female sex bias in FGFR3 somatic mutationswas observed in BCa.Well-powered individual participant data analyses addressing the possible confounding effects of other factors(eg,age,ethnicity,smoking status,muscle invasiveness,and molecular subtype),as well as analyses integrating omics and functional investigations,are warranted to further validate and explain the mechanisms of the current findings.
基金supported by the National Key Research and Development Program of China (2023YFC3605504)the Innovation Fund for Medical Sciences from the Chinese Academy of Medical Sciences (2021-I2M-1-003)the National High-Level Hospital Clinical Research Funding (2022-PUMCH-D-002 and 2022-PUMCH-B-098)
文摘Background: Methylmalonate semialdehyde dehydrogenase(ALDH6A1), encoded by the ALDH6A1 gene, is essential for the metabolic degradation of valine and thymine.Genetic alterations in ALDH6A1 lead to methylmalonate semialdehyde dehydrogenase deficiency(MMSDD), a rare disease with only five reported disease mutations, focusing on its molecular foundation but lacking in-depth mechanistic investigations. Therefore, the structural and biochemical properties of the ALDH6A1mutants have not yet been thoroughly examined.Methods: Wild-type(WT) and mutant ALDH6A1 were constructed as plasmids and purified after prokaryotic expression to obtain conformationally homogeneous and pure protein. The structures of ALDH6A1 mutants(P62S, Y172H & R535C, S262Y,P421S, and G446R) were solved using cryo-electron microscopy. Based on the results of ALDH6A1 WT, enzyme activity and thermal stability experiments of their mutants were performed to explore the ALDH6A1's biochemical characteristics.Results: This study presents a structural analysis of the ALDH6A1 mutants, P62S,Y172H & R535C, S262Y, P421S, and G446R at resolutions of 3.70, 2.92, 3.12, 3.47,and 3.00 Å, respectively. However, the electronic density of ALDH6A1 P421S is poor,and it is difficult to fit into this density. Furthermore, the root-mean-square deviation(r.m.s.d.) of ALDH6A1 WT with these mutants was significant. This study revealed a tetrameric structure with closely interacting monomers, except for ALDH6A1 P62S,which forms a dimer, and is consistent with the principles of the aldehyde dehydrogenase family. Moreover, these disease mutations also affect enzyme activity and thermal stability.Conclusions: Our findings shed light on disease mutations that contribute to the properties of ALDH6A1 and lead to the genesis of MMSDD from structural and biochemical perspectives, which holds promise as a potential theoretical basis for this rare disease.
基金Key Health Science and Technology Development Project of Nanjing City,Jiangsu Province,No.ZKX19038.
文摘BACKGROUND The SETD1B gene is instrumental in human intelligence and nerve development.Mutations in the SETD1B gene have been linked in recent studies to neurodevelopmental disorders,seizures,and language delay.CASE SUMMARY This study aimed to analyze the clinical manifestations and treatment of three patients suffering from mental retardation,epilepsy,and language delay resulting from a new mutation in the SETD1B gene.Three individuals with these symptoms were selected,and their clinical symptoms,gene test results,and treatment were analyzed.This article discusses the impact of the SETD1B gene mutation on patients and outlines the treatment approach.Among the three patients(two females and one male,aged 8,4,and 1,respectively),all exhibited psychomotor retardation,attention deficit,and hyperactivity disorder,and two had epilepsy.Antiepileptic treatment with sodium tripolyvalproate halted the seizures in the affected child,although mental development remained somewhat delayed.Whole exome sequencing revealed new mutations in the SETD1B gene for all patients,specifically with c.5473C>T(p.Arg1825trp),c.4120C>T(p.Gln1374*,593),c.14_15insC(p.His5Hisfs*33).CONCLUSION Possessing the SETD1B gene mutation may cause mental retardation accompanied by seizures and language delay.Although the exact mechanism is not fully understood,interventions such as drug therapy,rehabilitation training,and family support can assist patients in managing their symptoms and enhancing their quality of life.Furthermore,genetic testing supplies healthcare providers with more precise diagnostic and therapeutic guidance,informs families about genetic disease risks,and contributes to understanding disease pathogenesis and drug research and development.
基金This work was supported by the Natural Science Foundation of Guangdong Province(Grant No.2019A1515011354).
文摘Genome sequencing has revealed frequent mutations in Ras homolog family member A(RHOA)among various cancers with unique aberrant profiles and pathogenic effects,especially in peripheral T-cell lymphoma(PTCL).The discrete positional distribution and types of RHOA amino acid substitutions vary according to the tumor type,thereby leading to different functional and biological properties,which provide new insight into the molecular pathogenesis and potential targeted therapies for various tumors.However,the similarities and discrepancies in characteristics of RHOA mutations among various histologic subtypes of PTCL have not been fully elucidated.Herein we highlight the inconsistencies and complexities of the type and location of RHOA mutations and demonstrate the contribution of RHOA variants to the pathogenesis of PTCL by combining epigenetic abnormalities and activating multiple downstream pathways.The promising potential of targeting RHOA as a therapeutic modality is also outlined.This review provides new insight in the field of personalized medicine to improve the clinical outcomes for patients.
基金supported by the Applied Basic Research Programs of Science and Technology Commission Foundation of Jiangsu Province(No.BE2015684).
文摘Approximately 30%–40%of growth hormone–secreting pituitary adenomas(GHPAs)harbor somatic activating mutations in GNAS(αsubunit of stimulatory G protein).Mutations in GNAS are associated with clinical features of smaller and less invasive tumors.However,the role of GNAS mutations in the invasiveness of GHPAs is unclear.GNAS mutations were detected in GHPAs using a standard polymerase chain reaction(PCR)sequencing procedure.The expression of mutation-associated maternally expressed gene 3(MEG3)was evaluated with RT-qPCR.MEG3 was manipulated in GH3 cells using a lentiviral expression system.Cell invasion ability was measured using a Transwell assay,and epithelial–mesenchymal transition(EMT)-associated proteins were quantified by immunofluorescence and western blotting.Finally,a tumor cell xenograft mouse model was used to verify the effect of MEG3 on tumor growth and invasiveness.The invasiveness of GHPAs was significantly decreased in mice with mutated GNAS compared with that in mice with wild-type GNAS.Consistently,the invasiveness of mutant GNASexpressing GH3 cells decreased.MEG3 is uniquely expressed at high levels in GHPAs harboring mutated GNAS.Accordingly,MEG3 upregulation inhibited tumor cell invasion,and conversely,MEG3 downregulation increased tumor cell invasion.Mechanistically,GNAS mutations inhibit EMT in GHPAs.MEG3 in mutated GNAS cells prevented cell invasion through the inactivation of the Wnt/β-catenin signaling pathway,which was further validated in vivo.Our data suggest that GNAS mutations may suppress cell invasion in GHPAs by regulating EMT through the activation of the MEG3/Wnt/β-catenin signaling pathway.
基金funded by the National Natural Science Foundation of China(31972281)。
文摘Cyperus difformis L.is a troublesome weed in paddy fields and has attracted attention due to its resistance to acetohydroxyacid synthase(AHAS)inhibitors.It was found that the amino acid mutation in AHAS was the primary cause for the resistance of Cyperus difformis.However,the effect of different mutations on AHAS function is not clear in Cyperus difformis.To confirm the effect of mutations on AHAS function,six biotypes were collected,including Pro197Arg,Pro197Ser,Pro197Leu,Asp376Glu,Trp574Leu and wild type,from Hunan,Anhui,Jiangxi and Jiangsu provinces,China and the function of AHAS was characterized.The AHAS in vitro inhibition assay results indicated that the mutations decreased the sensitivity of AHAS to pyrazosulfuron-ethyl,in which the I_(50)(the half maximal inhibitory concentration)of wild type AHAS was 0.04μmol L^(-1)and Asp376Glu,Pro197Leu,Pro197Arg,Pro197Ser and Trp574Leu mutations were 3.98,11.50,40.38,38.19 and 311.43μmol L^(-1),respectively.In the determination of enzyme kinetics parameters,the Km and the maximum reaction velocity(Vmax)of the wild type were 5.18 mmol L^(-1)and 0.12 nmol mg^(-1)min^(-1),respectively,and the Km values of AHAS with Asp376Glu,Trp574Leu,Pro197Leu and Pro197Ser mutations were 0.38-0.93 times of the wild type.The Km value of the Pro197Arg mutation was 1.14times of the wild type,and the Vmax values of the five mutations were 1.17-3.33-fold compared to the wild type.It was found that the mutations increased the affinity of AHAS to the substrate,except for the Pro197Arg mutation.At a concentration of 0.0032-100 mmol L^(-1)branched-chain amino acids(BCAAs),the sensitivity of the other four mutant AHAS biotypes to feedback inhibition decreased,except for the Pro197Arg mutation.This study elucidated the effect of different mutations on AHAS function in Cyperus difformis and provided ideas for further study of resistance development.
基金financially supported by Laoshan Laboratory(LSKJ202203203)the National Natural Science Founda-tion of China(31961123002,32270435)+4 种基金the Fundamental Research Funds for the Central Universities of China(202041001)the Shan-dong Provincial Natural Science Foundation(ZR2023QC191)the Postdoctoral Fellowship Program of CPSF under Grant Number GZC20232504the Multidisciplinary University Research Initiative Award from the US Army Research Office(W911NF-09-1-0444)National Institutes of Health award(R35-GM122566 to ML)and(R35-GM131767 to MEW).
文摘Bacteria with functional DNA repair systems are expected to have low mutation rates due to strong natural selection for genomic stability.However,our study of the wild-type Streptococcus pneumoniae D39,a pathogen responsible for many common diseases,revealed a high spontaneous mutation rate of 0.02 per genome per cell division in mutation-accumulation(MA)lines.This rate is orders of magnitude higher than that of other non-mutator bacteria and is characterized by a high mutation bias in the A/T direction.The high mutation rate may have resulted from a reduction in the overall efficiency of selection,conferred by the tiny effective population size in nature.In line with this,S.pneumoniae D39 also exhibited the lowest DNA mismatch-repair(MMR)efficiency among bacteria.Treatment with the antibiotic penicillin did not elevate the mutation rate,as penicillin did not induce DNA damage and S.pneumoniae lacks a stress response pathway.Our findings suggested that the MA results are applicable to within-host scenarios and provide insights into pathogen evolution.
基金Supported by National High Level Hospital Clinical Research Funding,No.2023-NHLHCRF-YYPPLC-TJ-03.
文摘BACKGROUND RAS,BRAF,and mismatch repair(MMR)/microsatellite instability(MSI)are crucial biomarkers recommended by clinical practice guidelines for colorectal cancer(CRC).However,their characteristics and influencing factors in Chinese patients have not been thoroughly described.AIM To analyze the clinicopathological features of KRAS,NRAS,BRAF,and PIK3CA mutations and the DNA MMR status in CRC.METHODS We enrolled 2271 Chinese CRC patients at the China-Japan Friendship Hospital.MMR proteins were tested using immunohistochemical analysis,and the KRAS/NRAS/BRAF/PIK3CA mutations were determined using quantitative polymerase chain reaction.Microsatellite status was determined using an MSI detection kit.Statistical analyses were conducted using SPSS software and logistic regression.RESULTS The KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 44.6%,3.4%,3.7%,and 3.9% of CRC patients,respectively.KRAS mutations were more likely to occur in patients with moderate-to-high differentiation.BRAF mutations were more likely to occur in patients with right-sided CRC,poorly differentiated,or no perineural invasion.Deficient MMR(dMMR)was detected in 7.9% of all patients and 16.8% of those with mucinous adenocarcinomas.KRAS,NRAS,BRAF,and PIK3CA mutations were detected in 29.6%,1.1%,8.1%,and 22.3% of patients with dMMR,respectively.The dMMR was more likely to occur in patients with a family history of CRC,aged<50 years,right-sided CRC,poorly differentiated histology,no perineural invasion,and with carcinoma in situ,stage I,or stage II tumors.CONCLUSION This study analyzed the molecular profiles of KRAS,NRAS,BRAF,PIK3CA,and MMR/MSI in CRC,identifying key influencing factors,with implications for clinical management of CRC.
基金This work was supported by the Grant from Tianjin Municipal Natural Science Foundations (No. 033607311).
文摘Objective： To investigate the association between the mutations in lipoprotein lipase gene and hypertriglyceridemia （HTG）. Methods： The lipoprotein lipase （LPL） gene was screened for mutations in 386 Chinese subjects with （108 cases in the HTG group） or without HTG （278 cases in the control group）, by single-strand conformation polymorphism （SSCP） analysis and DNA sequencing. Results： One novel silent mutation L103L, one missense mutation P207L, three splicing mutations Int3/3＇ -ass/C（-6）→T, and the common S447X polymorphism has been identified in the whole coding region and exon-intron junctions of the LPL gene were examined. Heterozygous P207L found in the HTG group was the first case reported in Asia and subsequently another P207L heterozygote was found in the proband＇s family, all of which suggested that P207L was one of the causes of familial combined hyperlipidemia, but was not so prevalent as that in French Canadian. Int3/3＇-ass/C（-6）→T was found in both groups in the present study although it was regarded as a pathogenic variant to HTG earlier on. Moreover about the beneficial polymorphism S447X, there was also some supportive evidence that the levels of triglycerides （TG） in S447X carriers were significantly lower than noncarders in the subjects without HTG. Conclusions： The association between the LPL variants and HTG is quite complicated and versatile, genotyping of LPL in a larger-scale screening should be necessary and justifiable.
基金Supported by the National Natural Science Foundation,No.81974124and Taishan Scholar Project,No.tsqn20161071.
文摘BACKGROUND Adaptor protein,phosphotyrosine interacting with PH domain and leucine zipper 1(APPL1)plays a crucial role in regulating insulin signaling and glucose metabolism.Mutations in the APPL1 gene have been associated with the development of maturity-onset diabetes of the young type 14(MODY14).Currently,only two mutations[c.1655T>A(p.Leu552*)and c.281G>A p.(Asp94Asn)]have been identified in association with this disease.Given the limited understanding of MODY14,it is imperative to identify additional cases and carry out comprehensive research on MODY14 and APPL1 mutations.AIM To assess the pathogenicity of APPL1 gene mutations in diabetic patients and to characterize the functional role of the APPL1 domain.METHODS Patients exhibiting clinical signs and a medical history suggestive of MODY were screened for the study.Whole exome sequencing was performed on the patients as well as their family members.The pathogenicity of the identified APPL1 variants was predicted on the basis of bioinformatics analysis.In addition,the pathogenicity of the novel APPL1 variant was preliminarily evaluated through in vitro functional experiments.Finally,the impact of these variants on APPL1 protein expression and the insulin pathway were assessed,and the potential mechanism underlying the interaction between the APPL1 protein and the insulin receptor was further explored.RESULTS A total of five novel mutations were identified,including four missense mutations(Asp632Tyr,Arg633His,Arg532Gln,and Ile642Met)and one intronic mutation(1153-16A>T).Pathogenicity prediction analysis revealed that the Arg532Gln was pathogenic across all predictions.The Asp632Tyr and Arg633His variants also had pathogenicity based on MutationTaster.In addition,multiple alignment of amino acid sequences showed that the Arg532Gln,Asp632Tyr,and Arg633His variants were conserved across different species.Moreover,in in vitro functional experiments,both the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were found to downregulate the expression of APPL1 on both protein and mRNA levels,indicating their pathogenic nature.Therefore,based on the patient’s clinical and family history,combined with the results from bioinformatics analysis and functional experiment,the c.1894G>T(at Asp632Tyr)and c.1595G>A(at Arg532Gln)mutations were classified as pathogenic mutations.Importantly,all these mutations were located within the phosphotyrosinebinding domain of APPL1,which plays a critical role in the insulin sensitization effect.CONCLUSION This study provided new insights into the pathogenicity of APPL1 gene mutations in diabetes and revealed a potential target for the diagnosis and treatment of the disease.
文摘The severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)belongs to the genus Beta coronavirus and the family of Coronaviridae.It is a positive-sense,non-segmented single-strand RNA virus.Four common types of human coronaviruses circulate globally,particularly in the fall and winter seasons.They are responsible for 10%-30% of all mild upper respiratory tract infections in adults.These are 229E,NL63 of the Alfacoronaviridae family,OC43,and HKU1 of the Betacoronaviridae family.However,there are three highly pathogenic human coronaviruses:SARS-CoV-2,Middle East respiratory syndrome coronavirus,and the latest pandemic caused by the SARS-CoV-2 infection.All viruses,including SARS-CoV-2,have the inherent tendency to evolve.SARS-CoV-2 is still evolving in humans.Additionally,due to the development of herd immunity,prior infection,use of medication,vaccination,and antibodies,the viruses are facing immune pressure.During the replication process and due to immune pressure,the virus may undergo mutations.Several SARS-CoV-2 variants,including the variants of concern(VOCs),such as B.1.1.7(Alpha),B.1.351(Beta),B.1.617/B.1.617.2(Delta),P.1(Gamma),and B.1.1.529(Omicron)have been reported from various parts of the world.These VOCs contain several important mutations;some of them are on the spike proteins.These mutations may lead to enhanced infectivity,transmissibility,and decreased neutralization efficacy by monoclonal antibodies,convalescent sera,or vaccines.Mutations may also lead to a failure of detection by molecular diagnostic tests,leading to a delayed diagnosis,increased community spread,and delayed treatment.We searched PubMed,EMBASE,Covariant,the Stanford variant Database,and the CINAHL from December 2019 to February 2023 using the following search terms:VOC,SARS-CoV-2,Omicron,mutations in SARS-CoV-2,etc.This review discusses the various mutations and their impact on infectivity,transmissibility,and neutralization efficacy.
文摘In recent years, there has been a global rise in cases of papillary thyroid carcinoma (PTC), the predominant form of thyroid cancer. Advances in molecular biology have intensified the focus on the genetic mutations associated with this malignancy. Researchers have conducted extensive investigations into these mutations to elucidate their roles in the initiation, progression, treatment, and prognosis of PTC. This review synthesizes studies on the genetic mutations implicated in PTC, examining specific mutated genes, mechanisms of mutation, correlations with clinicopathological features, and their influence on treatment outcomes and prognosis. The objective is to provide a theoretical framework for enhancing the diagnosis, treatment, and prognostic assessment of PTC in the future.
