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
In this study,we used the modified CRISPR/Cas9 system to produce targeted point mutations in cauliflower.Acetolactate synthase(ALS)and Centromere-specific histone H3 variant(CENH3)genes were selected as the base-editi...In this study,we used the modified CRISPR/Cas9 system to produce targeted point mutations in cauliflower.Acetolactate synthase(ALS)and Centromere-specific histone H3 variant(CENH3)genes were selected as the base-editing targets and hypocotyls of cauliflower were used as explants.For ALS gene,a C-to-T conversion in the Pro182 codon(CCT)can alter the encoded amino acid,likely resulting in herbicide resistance,and a C-to-T mutation in the Leu133 codon(CTT)in the CENH3 gene may produce a haploid inducer.Results indicated that the transformation efficiency was 1.8%–4.5%and the mutation efficiencies for the ALS and CENH3 genes were approximately 22%and 87%,respectively.The ALS mutant cauliflower showed strong herbicide resistance,with possible immediate implications for broadleaf weed control in cauliflower fields.展开更多
Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cycli...Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cyclin D cdk4,cyclin D cdk6 complex and have been implicated in a wide variety of cancer types,including the germline of patients with familial melanoma.In order to investigate and compare the status of p16,p15 gene in primary tumors and cell lines,we examined 357 primary tumors and 29 cell lines derived from diverse tumor types.In addition to analysis of these primary tumors and cell lines,blood specimens from 91 patients either with sporadic multiple cancers or from cancer prone families were also analyzed.The data showed the following:1)Homozygous deletions of p16,p15 were comparatively rare and far less common than previously reported,although hemizygous deletions were observed in a significant fraction of many tumor types;2)the incidence of p16,p15 deletions(either homozygous deletions or heterozygous deletions)varied significantly among different tumor types;3)most deletions involved in both p16 and p15 genes;4)sequence variations in the coding sequence of p16,p15 were comparatively rare among these tumor types,though mutations and polymorphisms were identified;5)some tumors which showed LOH at 9p,containing p16 and p15 gene,did not show deletions or point mutations in the p16,p15 gene.6)In a subset of retinoblastoma and osteosarcoma where no Rb gene mutations were present a significant fraction was found to contain p16,p15 gene deletions.展开更多
Genetic mutations are important molecular biomarkers for cancer diagnosis and surveillance. Therefore, the development of methods for mutation detection characterized with straightforward, highly specific and sensitiv...Genetic mutations are important molecular biomarkers for cancer diagnosis and surveillance. Therefore, the development of methods for mutation detection characterized with straightforward, highly specific and sensitive to low-level mutations within various sequence contexts is extremely needed. Although some of the currently available methods have shown very encouraging results, their discrimination efficiency is still very low. Herein, we demonstrate a fluorescent probe coupled with blocker and property of melting temperature discrimination, which is able to identify the presence of known or unknown single-base variations at abundances down to 0.1% within 20 min. The discrimination factors between the perfect-match target and single-base mismatched target are determined to be 10.15–38.48. The method is sequence independent, which assures a wide range of application. The new method would be an ideal choice for high-throughput in vitro diagnosis and precise clinical treatment.展开更多
Point mutations can be used as biomarkers to perform diagnosis for diseases. In this study, a nanorobot for low-abundance point mutation enrichment was constructed using DNA origami. The novel design achieved limits o...Point mutations can be used as biomarkers to perform diagnosis for diseases. In this study, a nanorobot for low-abundance point mutation enrichment was constructed using DNA origami. The novel design achieved limits of detection of 0.1% and 1% for synthesized DNA samples and clinical gene samples, respectively. Resettability was a key property of this method, which also involved a simpler process, lower cost and shorter detection duration than traditional enrichment methods. This novel DNA nanorobot may enable the detection of tumor markers, potentially facilitating early cancer diagnosis.展开更多
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
Following the publication of Liu et al.(2024),an error was identified in Figure 4B,in which the image representing the lung from the E529G group was inadvertently duplicated with the image of the lung from the WT grou...Following the publication of Liu et al.(2024),an error was identified in Figure 4B,in which the image representing the lung from the E529G group was inadvertently duplicated with the image of the lung from the WT group during figure preparation.展开更多
Background It is still unclear whether viral genetic variability influences response to interferon(IFN) α treatment Recent reports suggest that IFN α effects may be associated with hepatitis B virus(HBV) post ...Background It is still unclear whether viral genetic variability influences response to interferon(IFN) α treatment Recent reports suggest that IFN α effects may be associated with hepatitis B virus(HBV) post transcriptional regulation This study was designed to explore the heterogeneity of HBV post transcriptional regulatory elements (HPRE) and the relationship between the diversity of HPRE and the response to IFN α treatment Methods The HPRE sequences from 31 Chinese patients infected with HBV were determined by directly sequencing of polymerase chain reaction (PCR) product, and comparing them to those from Caucasian patients Subsequently, eukaryotic expression vectors containing HPRE at various points were constructed and transfected into HepG2 cells, which were then exposed to recombinant human cytokines Results The T to C point mutation at nt 1504 and the C to T (G) at nt 1508 in HPRE were found in 21 and 19 patients with chronic hepatitis B, respectively; the C to T point mutation at nt 1509 was found in 17 patients These point mutations did not exist in the HPRE of the Caucasian patients The activity of the CAT gene obviously increased in the case of T to C point mutation at nt 1504, but did not change in the case of the C to T (G) mutations at nt 1508 and 1509 The activity of the CAT gene at these point mutations of HPRE could be inhibited by IFN α/γ and tumor necrosis factor (TNF) α except for the point mutations at nt 1508 of HPRE which may escape the suppression role of IFN α on HPRE Conclusions There are point mutations between the HPRE of Chinese and Caucasian HBV patients, which might be correlated with response to IFN α The variation of HPRE might affect the function of HPRE and influence the regulative function of IFN α other than that of IFN γ or TNF α on HPRE展开更多
Objective To study the relation between point mutations at nt3243 and nt8344 of muscle mitochondrial DNA from patients with mitochondrial encephalomyopathies and phenotypes. Methods DNA was extracted from muscle speci...Objective To study the relation between point mutations at nt3243 and nt8344 of muscle mitochondrial DNA from patients with mitochondrial encephalomyopathies and phenotypes. Methods DNA was extracted from muscle specimens from 5 patients with mitochondrial encephalomyopathies and amplified by PCR method, using corresponding oligonucleotide primers. DNA fragments were digested with restriction enzymes BglⅠ and ApaⅠ, then the digested DNA fragments were analyzed with an electrophoresis method.Results The point mutation at nt3243 of mtDNA was found in 2 patients, one with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) and another with myoclonic epilepsy with ragged red fibers (MERRF). The point mutation at nt8344 was found in 2 patients with MERRF, including the one with point mutation at nt3243.Conclusion The point mutation of DNA at nt3243 correlated with MELAS and nt8344 correlated with MERRF. In addition, the detection of point mutations at both nt3243 and nt8344 in a patient with MERRF shows the association of mutation with diversity in clinical manifestations of mitochondrial encephalomyopathies.展开更多
The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide.Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridizati...The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide.Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridization facilitates host-jumping.However,the pervasive clonal lineages of M.oryzae observed in natural fields contradict this expectation.A better understanding of the roles of recombination and the fungi-specific repeat-induced point mutation(RIP)in shaping its evolutionary trajectory is essential to bridge this knowledge gap.Here we systematically investigate the RIP and recombination landscapes in M.oryzae using a whole genome sequencing data from 252 population samples and 92 cross progenies.Our data reveal that the RIP can robustly capture the population history of M.oryzae,and we provide accurate estimations of the recombination and RIP rates across different M.oryzae clades.Significantly,our results highlight a parent-of-origin bias in both recombination and RIP rates,tightly associating with their sexual potential and variations of effector proteins.This bias suggests a critical trade-off between generating novel allelic combinations in the sexual cycle to facilitate host-jumping and stimulating transposon-associated diversification of effectors in the asexual cycle to facilitate host coevolution.These findings provide unique insights into understanding the evolution of blast fungus.展开更多
Porcine reproductive and respiratory syndrome(PRRS)is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus(PRRSV),resulting in substantial economic losses in the swine industry.Modifyin...Porcine reproductive and respiratory syndrome(PRRS)is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus(PRRSV),resulting in substantial economic losses in the swine industry.Modifying the CD163 SRCR5 domain,either through deletion or substitution,can eff1ectively confer resistance to PRRSV infection in pigs.However,large fragment modifications in pigs inevitably raise concerns about potential adverse effects on growth performance.Reducing the impact of genetic modifications on normal physiological functions is a promising direction for developing PRRSV-resistant pigs.In the current study,we identified a specific functional amino acid in CD163 that influences PRRSV proliferation.Viral infection experiments conducted on Marc145 and PK-15CD163 cells illustrated that the mE535G or corresponding pE529G mutations markedly inhibited highly pathogenic PRRSV(HP-PRRSV)proliferation by preventing viral binding and entry.Furthermore,individual viral challenge tests revealed that pigs with the E529G mutation had viral loads two orders of magnitude lower than wild-type(WT)pigs,confirming effective resistance to HP-PRRSV.Examination of the physiological indicators and scavenger function of CD163 verified no significant differences between the WT and E529G pigs.These findings suggest that E529G pigs can be used for breeding PRRSV-resistant pigs,providing novel insights into controlling future PRRSV outbreaks.展开更多
The emergence of influenza virus A pandemic H1N1 in April 2009 marked the first pandemic of the 21st century.In this study,we observed significant differences in the polymerase activities of two clinical 2009 H1N1 inf...The emergence of influenza virus A pandemic H1N1 in April 2009 marked the first pandemic of the 21st century.In this study,we observed significant differences in the polymerase activities of two clinical 2009 H1N1 influenza A virus isolates from Chinese and Japanese patients.Sequence comparison of the three main protein subunits(PB2,PB1,and PA)of the viral RNA-dependent RNA polymerase complex and subsequent mutational analysis revealed that a single amino acid substitution(E206K)was responsible for the observed impaired replication phenotype.Further in vitro experiments showed that presence of PAE206K decreased the replication of influenza A/WSN/33 virus in mammalian cells and a reduction in the virus’s pathogenicity in vivo.Mechanistic studies revealed that PAE206K is a temperature-sensitive mutant associated with the inability to transport PB1–PA complex to the nucleus at high temperature(39.5℃).Hence,this naturally occurring variant in the PA protein represents an ideal candidate mutation for the development of live attenuated influenza vaccines.展开更多
AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors....AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors. METHODS The overexpression and point mutations of tumor suppressor gene p53 in 38 cases of HCC were detected by a sensitive antigen retrieval fluid (ARF) immunohistochemical method and polymerase chain re- action(PCR)-restriction fragment length polymorphism (RFLP),and single strand conformation polymorphism (SSCP)-silver staining analysis. RESULTS The results showed that 16 of 38 HCCs had positive p53 protein (42.1%),7 HCCs had p53 mutation at 249 (18.4 % ) and 2 HCCS had point muta- tion within exon 7 other than 249. Among 9 cases of HCC with mutations,8 cases demonstrated positive p53 protein,its coincidental rate was 88.9%. The overexpression and mutations of p53 were significantly related to the differentiation and metastasis of HCCs. The frequency of p53 mutations was consistent with high prevalence of HBV and a moderate aflatoxin B1 (AFB1) exposure in our area. CONCLUSIONS The results suggest that AFB1 acts synergistically with HBV in the generation of p53 mutations. Furthermore,dietary exposure to AFB1 may mainly contribute to the tumor specific mutation at codon 249,while HBV may account for other scattered mutations in HCC.展开更多
Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinat...Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinate dehydrogenase inhibitor(SDHI),has been found as a promising fungicide for the efficient control of SCLB,however,resistance of C.heterostrophus to Pyd has not been studied well.Here,five Pyd-resistant mutants were generated through fungicide adaptation.Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD,with three genotypes:ChSdhB^(H277Y),ChSdhB^(I279T)and ChSdhD^(H133Y),exhibiting two distinct categories of resistance:high resistance(HR)and moderate resistance(MR),among which the resistance factors were 214.22 and 44.33-53.67,respectively.These mutants were more pathogenic than the wild-type parental strains,but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants,indicating a significant fitness cost associated with resistance to Pyd.In addition,this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram.However,no cross-resistance was found between Pyd and other classes of fungicides,including prochloraz,fludioxonil,iprodione or pyraclostrobin.Homology modeling and molecular docking further confirmed that point mutations of ChSdhB^(H277Y),ChSdhB^(I279T),and ChSdhD^(H133Y)could reduce binding affinity between Pyd and its target subunits from-74.07,-74.07,-152.52 kcal mol^(-1)to-3.90,-4.95,-9.93 kcal mol^(-1),respectively.These findings not only provided valuable insights for managing SCLB caused by C.heterostrophus,but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd.展开更多
Chronic pancreatitis(CP)is a progressive and irreversible fibroinflammatory disease that markedly increases susceptibility to pancreatic cancer and remains without effective targeted therapies.Among the genetic contri...Chronic pancreatitis(CP)is a progressive and irreversible fibroinflammatory disease that markedly increases susceptibility to pancreatic cancer and remains without effective targeted therapies.Among the genetic contributors to CP,the carboxypeptidase A1 p.Ser282Pro(CPA1^(S282P))variant has been proposed to promote disease through misfolding-induced endoplasmic reticulum stress(ERS),although the broader pathogenic landscape remains incompletely defined.This study generated a rabbit model mimicking the human CPA1S282P mutation using the SpRY-ABE-8.17 system.Homozygous CPA1^(S282P)rabbits exhibited characteristic human CP phenotypes following alcohol induction,including visceral pain,elevated serum lipase and amylase,inflammatory cell infiltration,and extensive pancreatic fibrosis.Biochemical analyses confirmed that the p.S282P mutation induced CPA1 misfolding and elevated the expression of ERS markers GRP78 and CHOP in both transfected HEK293T cells and homozygous mutant rabbits.Notably,the CPA1^(S282P)mutation markedly disrupted intra-pancreatic lipid homeostasis,contributing to the development of CP in mutant rabbits.This study successfully established the first rabbit model of CP that accurately recapitulates CP caused by a defined human point mutation.Additionally,this study provides insights into a previously unrecognized link between CPA1 and intra-pancreatic lipid metabolism,offering a foundation for identifying novel therapeutic targets for human CP.展开更多
Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological el...Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological element trends were analyzed using theβ-z-h three-parameter indication method.The Mann-Kendall,Pettitt,moving T,and Yamamoto methods were used to test the mutation point of hydrological elements.The Budyko framework was used to quantitatively assess the impacts of climate change and multiple human activities on runoff reduction.The results showed that(1):Precipitation(PRE),potential evapotranspiration(E0),and temperature(TEM)showed increasing trends;runoff in the Huangfuchuan,Gushanchuan,Kuye River,Tuwei River,Wuding River,Qingjian River,and Yanhe River catchments showed decreasing trends(HFC,GSC,KYR,TWR,WDR,QJR,YR);whereas runoff in the Jialu River(JLR)catchment showed a“V-shaped”trend from 1980 to2020.(2)Runoff was positively correlated with PRE and negatively correlated with E0and the subsurface index(n),with the elasticity coefficients of PRE,E0,and n showing an increasing trend in the change period.(3)Human activities were a key factor in runoff reduction,although the impact of different human activities showed spatial variations.This study provides a scientific foundation for achieving the sustainable development of water resources in mining areas.展开更多
AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of C...AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of China, these factors are not so important in the etiology of HCC. Therefore, the point mutation of p53 exon7 may also be different than that in HCC-prevalent areas of China. The aim of this study is to investigate the status and carcinogenic role of the point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province, a non-HCC-prevalent area in China. METHODS: PCR PCR-SSCP and PCR-RFLP were applied to analyze the homozygous deletion and point mutation of p53 exon7 in HCC samples from Anhui, which were confirmed by DNA sequencing and Genbank comparison. RESULTS: In the 38 samples of hepatocellular carcinoma, no homozygous deletion of p53 exon7 was detected and point mutations of p53 exon7 were found in 4 cases, which were found to be heterozygous mutation of codon 249 with a mutation rate of 10.53%(4/38). The third base mutation(G-T) of p53 codon 249 was found by DNA sequencing and Genbank comparison. CONCLUSION: The incidence of point mutation of p53 codon 249 is lower in hepatocellular carcinoma and the heterozygous mutation of p53 exon7 found in these patients only indicate that they have genetic susceptibility to HCC. p53 codon 249 is a hotspot of p53 exon7 point mutation, suggesting that the point mutation of p53 exon 7 may not play a major role in the carcinogenesis of HCC in Anhui Province, a non-HCC-prevalent area in China.展开更多
AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H.pylori)and determine their association with therapeutic failure.METHODS PCR products of 23S rRNA gene V domain ...AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H.pylori)and determine their association with therapeutic failure.METHODS PCR products of 23S rRNA gene V domain of 74 H.pylori isolates;34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC)population:TumacoColombia,and 5 from a high-risk population:TuquerresColombia)and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres)were sequenced using capillary electrophoresis.The concordance between mutations of V domain 23S rRNA gene of H.pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H.pylori mutationsand clarithromycin resistance.RESULTS23S rRNA gene from H.pylori was amplified in 56/74 isolates,of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres,respectively).In 17 resistant isolates(13 from Tumaco and 4 from Túquerres)the following mutations were found:A1593 T1,A1653 G2,C1770 T,C1954 T1,and G1827 C in isolates from Tumaco,and A2144 G from Túquerres.The mutations T2183 C,A2144 G and C2196 T in H.pylori isolates resistant to clarithromycin from Colombia are reported for the first time.No association between the H.pylori mutations and in vitro clarithromycin resistance was found.However,therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H.pylori(κ=0.71).CONCLUSION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23S rRNA gene in clarithromycinresistant H.pylori.展开更多
Generation of mouse models carrying a defined point mutation,especially disease-related point mutations,is of considerable interest for research in biology and medicine.The standard method based on embryonic stem cell...Generation of mouse models carrying a defined point mutation,especially disease-related point mutations,is of considerable interest for research in biology and medicine.The standard method based on embryonic stem cell（ESC）-mediated homologous recombination（HR）is time-and labor-consuming.展开更多
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partly funded by the project of technology innovation ability from Beijing Academy of Agriculture and Forestry Sciences (Grant Nos. KJCX20200401, KJCX20200205 and KJCX20200113)the Natural Science Foundation of China (Grant No. 31972401)
文摘In this study,we used the modified CRISPR/Cas9 system to produce targeted point mutations in cauliflower.Acetolactate synthase(ALS)and Centromere-specific histone H3 variant(CENH3)genes were selected as the base-editing targets and hypocotyls of cauliflower were used as explants.For ALS gene,a C-to-T conversion in the Pro182 codon(CCT)can alter the encoded amino acid,likely resulting in herbicide resistance,and a C-to-T mutation in the Leu133 codon(CTT)in the CENH3 gene may produce a haploid inducer.Results indicated that the transformation efficiency was 1.8%–4.5%and the mutation efficiencies for the ALS and CENH3 genes were approximately 22%and 87%,respectively.The ALS mutant cauliflower showed strong herbicide resistance,with possible immediate implications for broadleaf weed control in cauliflower fields.
文摘Aberrations of chromosome 9 p21 22 are involved in the genesis of many forms of cancer.The gene p16 and p15 have been assigned to this region.Both p16 and p15 are an inhibitor of cyclin D cdk4,cyclin D cdk6 complex and have been implicated in a wide variety of cancer types,including the germline of patients with familial melanoma.In order to investigate and compare the status of p16,p15 gene in primary tumors and cell lines,we examined 357 primary tumors and 29 cell lines derived from diverse tumor types.In addition to analysis of these primary tumors and cell lines,blood specimens from 91 patients either with sporadic multiple cancers or from cancer prone families were also analyzed.The data showed the following:1)Homozygous deletions of p16,p15 were comparatively rare and far less common than previously reported,although hemizygous deletions were observed in a significant fraction of many tumor types;2)the incidence of p16,p15 deletions(either homozygous deletions or heterozygous deletions)varied significantly among different tumor types;3)most deletions involved in both p16 and p15 genes;4)sequence variations in the coding sequence of p16,p15 were comparatively rare among these tumor types,though mutations and polymorphisms were identified;5)some tumors which showed LOH at 9p,containing p16 and p15 gene,did not show deletions or point mutations in the p16,p15 gene.6)In a subset of retinoblastoma and osteosarcoma where no Rb gene mutations were present a significant fraction was found to contain p16,p15 gene deletions.
文摘Genetic mutations are important molecular biomarkers for cancer diagnosis and surveillance. Therefore, the development of methods for mutation detection characterized with straightforward, highly specific and sensitive to low-level mutations within various sequence contexts is extremely needed. Although some of the currently available methods have shown very encouraging results, their discrimination efficiency is still very low. Herein, we demonstrate a fluorescent probe coupled with blocker and property of melting temperature discrimination, which is able to identify the presence of known or unknown single-base variations at abundances down to 0.1% within 20 min. The discrimination factors between the perfect-match target and single-base mismatched target are determined to be 10.15–38.48. The method is sequence independent, which assures a wide range of application. The new method would be an ideal choice for high-throughput in vitro diagnosis and precise clinical treatment.
基金funded by the National Key R&D Program of China (Nos. 2018YFA0903500, 2018YFC0114600)the National Natural Science Foundation of China (Nos. 51703073, 22077042)the Fundamental Research Funds for the Central University (No.2021yjs CXCY114, China)。
文摘Point mutations can be used as biomarkers to perform diagnosis for diseases. In this study, a nanorobot for low-abundance point mutation enrichment was constructed using DNA origami. The novel design achieved limits of detection of 0.1% and 1% for synthesized DNA samples and clinical gene samples, respectively. Resettability was a key property of this method, which also involved a simpler process, lower cost and shorter detection duration than traditional enrichment methods. This novel DNA nanorobot may enable the detection of tumor markers, potentially facilitating early cancer diagnosis.
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.
文摘Following the publication of Liu et al.(2024),an error was identified in Figure 4B,in which the image representing the lung from the E529G group was inadvertently duplicated with the image of the lung from the WT group during figure preparation.
文摘Background It is still unclear whether viral genetic variability influences response to interferon(IFN) α treatment Recent reports suggest that IFN α effects may be associated with hepatitis B virus(HBV) post transcriptional regulation This study was designed to explore the heterogeneity of HBV post transcriptional regulatory elements (HPRE) and the relationship between the diversity of HPRE and the response to IFN α treatment Methods The HPRE sequences from 31 Chinese patients infected with HBV were determined by directly sequencing of polymerase chain reaction (PCR) product, and comparing them to those from Caucasian patients Subsequently, eukaryotic expression vectors containing HPRE at various points were constructed and transfected into HepG2 cells, which were then exposed to recombinant human cytokines Results The T to C point mutation at nt 1504 and the C to T (G) at nt 1508 in HPRE were found in 21 and 19 patients with chronic hepatitis B, respectively; the C to T point mutation at nt 1509 was found in 17 patients These point mutations did not exist in the HPRE of the Caucasian patients The activity of the CAT gene obviously increased in the case of T to C point mutation at nt 1504, but did not change in the case of the C to T (G) mutations at nt 1508 and 1509 The activity of the CAT gene at these point mutations of HPRE could be inhibited by IFN α/γ and tumor necrosis factor (TNF) α except for the point mutations at nt 1508 of HPRE which may escape the suppression role of IFN α on HPRE Conclusions There are point mutations between the HPRE of Chinese and Caucasian HBV patients, which might be correlated with response to IFN α The variation of HPRE might affect the function of HPRE and influence the regulative function of IFN α other than that of IFN γ or TNF α on HPRE
文摘Objective To study the relation between point mutations at nt3243 and nt8344 of muscle mitochondrial DNA from patients with mitochondrial encephalomyopathies and phenotypes. Methods DNA was extracted from muscle specimens from 5 patients with mitochondrial encephalomyopathies and amplified by PCR method, using corresponding oligonucleotide primers. DNA fragments were digested with restriction enzymes BglⅠ and ApaⅠ, then the digested DNA fragments were analyzed with an electrophoresis method.Results The point mutation at nt3243 of mtDNA was found in 2 patients, one with mitochondrial encephalomyopathy, lactic acidosis and stroke-like episodes (MELAS) and another with myoclonic epilepsy with ragged red fibers (MERRF). The point mutation at nt8344 was found in 2 patients with MERRF, including the one with point mutation at nt3243.Conclusion The point mutation of DNA at nt3243 correlated with MELAS and nt8344 correlated with MERRF. In addition, the detection of point mutations at both nt3243 and nt8344 in a patient with MERRF shows the association of mutation with diversity in clinical manifestations of mitochondrial encephalomyopathies.
基金funded by the National Natural Science Foundation of China(32270664 and 32170327)the National Key Research and Development Program of China(2023YFD2200102 and 2023YFD2200104)Jiangsu Collaborative Innovation Center for Modern Crop Production。
文摘The fungal disease caused by Magnaporthe oryzae is one of the most devastating diseases that endanger many crops worldwide.Evidence shows that sexual reproduction can be advantageous for fungal diseases as hybridization facilitates host-jumping.However,the pervasive clonal lineages of M.oryzae observed in natural fields contradict this expectation.A better understanding of the roles of recombination and the fungi-specific repeat-induced point mutation(RIP)in shaping its evolutionary trajectory is essential to bridge this knowledge gap.Here we systematically investigate the RIP and recombination landscapes in M.oryzae using a whole genome sequencing data from 252 population samples and 92 cross progenies.Our data reveal that the RIP can robustly capture the population history of M.oryzae,and we provide accurate estimations of the recombination and RIP rates across different M.oryzae clades.Significantly,our results highlight a parent-of-origin bias in both recombination and RIP rates,tightly associating with their sexual potential and variations of effector proteins.This bias suggests a critical trade-off between generating novel allelic combinations in the sexual cycle to facilitate host-jumping and stimulating transposon-associated diversification of effectors in the asexual cycle to facilitate host coevolution.These findings provide unique insights into understanding the evolution of blast fungus.
基金Major Scientific and Technological Projects in Agricultural Biological Breeding of China(2023ZD0404302)Youth Program of National Natural Science Foundation of China(32202754)。
文摘Porcine reproductive and respiratory syndrome(PRRS)is a globally prevalent contagious disease caused by the positive-strand RNA PRRS virus(PRRSV),resulting in substantial economic losses in the swine industry.Modifying the CD163 SRCR5 domain,either through deletion or substitution,can eff1ectively confer resistance to PRRSV infection in pigs.However,large fragment modifications in pigs inevitably raise concerns about potential adverse effects on growth performance.Reducing the impact of genetic modifications on normal physiological functions is a promising direction for developing PRRSV-resistant pigs.In the current study,we identified a specific functional amino acid in CD163 that influences PRRSV proliferation.Viral infection experiments conducted on Marc145 and PK-15CD163 cells illustrated that the mE535G or corresponding pE529G mutations markedly inhibited highly pathogenic PRRSV(HP-PRRSV)proliferation by preventing viral binding and entry.Furthermore,individual viral challenge tests revealed that pigs with the E529G mutation had viral loads two orders of magnitude lower than wild-type(WT)pigs,confirming effective resistance to HP-PRRSV.Examination of the physiological indicators and scavenger function of CD163 verified no significant differences between the WT and E529G pigs.These findings suggest that E529G pigs can be used for breeding PRRSV-resistant pigs,providing novel insights into controlling future PRRSV outbreaks.
基金funded by grants from Beijing Natural Science Foundation(M22031)National Key R&D Program of China(2022YFF1203200,2022YFE0202600)+1 种基金Chinese Academy of Medical Sciences(2016-12M-1-014)National Natural Science Foundation of China(81871669,32070173,31471329 and 31601151).
文摘The emergence of influenza virus A pandemic H1N1 in April 2009 marked the first pandemic of the 21st century.In this study,we observed significant differences in the polymerase activities of two clinical 2009 H1N1 influenza A virus isolates from Chinese and Japanese patients.Sequence comparison of the three main protein subunits(PB2,PB1,and PA)of the viral RNA-dependent RNA polymerase complex and subsequent mutational analysis revealed that a single amino acid substitution(E206K)was responsible for the observed impaired replication phenotype.Further in vitro experiments showed that presence of PAE206K decreased the replication of influenza A/WSN/33 virus in mammalian cells and a reduction in the virus’s pathogenicity in vivo.Mechanistic studies revealed that PAE206K is a temperature-sensitive mutant associated with the inability to transport PB1–PA complex to the nucleus at high temperature(39.5℃).Hence,this naturally occurring variant in the PA protein represents an ideal candidate mutation for the development of live attenuated influenza vaccines.
文摘AIMS To examine the prevalance of p53 mutations in hepatocellular carcinoma (HCC) from Chongqing area and the relationship between the p53 mutations and clinicopathological features of HCC,as well as the risk factors. METHODS The overexpression and point mutations of tumor suppressor gene p53 in 38 cases of HCC were detected by a sensitive antigen retrieval fluid (ARF) immunohistochemical method and polymerase chain re- action(PCR)-restriction fragment length polymorphism (RFLP),and single strand conformation polymorphism (SSCP)-silver staining analysis. RESULTS The results showed that 16 of 38 HCCs had positive p53 protein (42.1%),7 HCCs had p53 mutation at 249 (18.4 % ) and 2 HCCS had point muta- tion within exon 7 other than 249. Among 9 cases of HCC with mutations,8 cases demonstrated positive p53 protein,its coincidental rate was 88.9%. The overexpression and mutations of p53 were significantly related to the differentiation and metastasis of HCCs. The frequency of p53 mutations was consistent with high prevalence of HBV and a moderate aflatoxin B1 (AFB1) exposure in our area. CONCLUSIONS The results suggest that AFB1 acts synergistically with HBV in the generation of p53 mutations. Furthermore,dietary exposure to AFB1 may mainly contribute to the tumor specific mutation at codon 249,while HBV may account for other scattered mutations in HCC.
基金supported by the National Key Research and Development Program of China(2023YFD1401504)the Open Project of Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests,China(PKLPRMGVP202402)+3 种基金the Programs for the Scientific Research Activities of Academic and Technical Leaders of Anhui Province,China(2020D251)the Development Fund for Talent Personnel of Anhui Agricultural University,China(rc342006)the University Synergy Innovation Program of Anhui Province,China(GXXT-2021-059)Anhui Province Agricultural Eco-Environmental Protection and Quality Safety Industry Technology System,China。
文摘Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinate dehydrogenase inhibitor(SDHI),has been found as a promising fungicide for the efficient control of SCLB,however,resistance of C.heterostrophus to Pyd has not been studied well.Here,five Pyd-resistant mutants were generated through fungicide adaptation.Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD,with three genotypes:ChSdhB^(H277Y),ChSdhB^(I279T)and ChSdhD^(H133Y),exhibiting two distinct categories of resistance:high resistance(HR)and moderate resistance(MR),among which the resistance factors were 214.22 and 44.33-53.67,respectively.These mutants were more pathogenic than the wild-type parental strains,but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants,indicating a significant fitness cost associated with resistance to Pyd.In addition,this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram.However,no cross-resistance was found between Pyd and other classes of fungicides,including prochloraz,fludioxonil,iprodione or pyraclostrobin.Homology modeling and molecular docking further confirmed that point mutations of ChSdhB^(H277Y),ChSdhB^(I279T),and ChSdhD^(H133Y)could reduce binding affinity between Pyd and its target subunits from-74.07,-74.07,-152.52 kcal mol^(-1)to-3.90,-4.95,-9.93 kcal mol^(-1),respectively.These findings not only provided valuable insights for managing SCLB caused by C.heterostrophus,but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd.
基金supported by the Jilin Provincial Department of Education Science and Technology Research Project(JJKH20231141K)Natural Science Foundation of Jilin Province of China(20230101154JC)Young Elite Scientists Sponsorship Program by CAST(2022QNRC001)。
文摘Chronic pancreatitis(CP)is a progressive and irreversible fibroinflammatory disease that markedly increases susceptibility to pancreatic cancer and remains without effective targeted therapies.Among the genetic contributors to CP,the carboxypeptidase A1 p.Ser282Pro(CPA1^(S282P))variant has been proposed to promote disease through misfolding-induced endoplasmic reticulum stress(ERS),although the broader pathogenic landscape remains incompletely defined.This study generated a rabbit model mimicking the human CPA1S282P mutation using the SpRY-ABE-8.17 system.Homozygous CPA1^(S282P)rabbits exhibited characteristic human CP phenotypes following alcohol induction,including visceral pain,elevated serum lipase and amylase,inflammatory cell infiltration,and extensive pancreatic fibrosis.Biochemical analyses confirmed that the p.S282P mutation induced CPA1 misfolding and elevated the expression of ERS markers GRP78 and CHOP in both transfected HEK293T cells and homozygous mutant rabbits.Notably,the CPA1^(S282P)mutation markedly disrupted intra-pancreatic lipid homeostasis,contributing to the development of CP in mutant rabbits.This study successfully established the first rabbit model of CP that accurately recapitulates CP caused by a defined human point mutation.Additionally,this study provides insights into a previously unrecognized link between CPA1 and intra-pancreatic lipid metabolism,offering a foundation for identifying novel therapeutic targets for human CP.
基金Department of Water Resources of Shaanxi Province of China,No.2023slkj-8National Natural Science Foundation of China,No.51779209。
文摘Studying runoff characteristics and quantifying human activities’impact on northern Shaanxi,a crucial mineral resource area in China,is crucial to alleviate water resource contradictions.In this study,hydrological element trends were analyzed using theβ-z-h three-parameter indication method.The Mann-Kendall,Pettitt,moving T,and Yamamoto methods were used to test the mutation point of hydrological elements.The Budyko framework was used to quantitatively assess the impacts of climate change and multiple human activities on runoff reduction.The results showed that(1):Precipitation(PRE),potential evapotranspiration(E0),and temperature(TEM)showed increasing trends;runoff in the Huangfuchuan,Gushanchuan,Kuye River,Tuwei River,Wuding River,Qingjian River,and Yanhe River catchments showed decreasing trends(HFC,GSC,KYR,TWR,WDR,QJR,YR);whereas runoff in the Jialu River(JLR)catchment showed a“V-shaped”trend from 1980 to2020.(2)Runoff was positively correlated with PRE and negatively correlated with E0and the subsurface index(n),with the elasticity coefficients of PRE,E0,and n showing an increasing trend in the change period.(3)Human activities were a key factor in runoff reduction,although the impact of different human activities showed spatial variations.This study provides a scientific foundation for achieving the sustainable development of water resources in mining areas.
基金the Natural Science Foundation of Anhui Province,No.99044312(WY) and No.9741006(LX)Natural Science Foundation of Anhui Educational Commission,No.JL-97-077(WY).
文摘AIM: In hepatocellular carcinoma (HCC) prevalent areas of China, the point mutation of p53 exon7 is highly correlated with Hepatitis B virus(HBV) infection and aflatoxin B intake. While in non-HCC-prevalent areas of China, these factors are not so important in the etiology of HCC. Therefore, the point mutation of p53 exon7 may also be different than that in HCC-prevalent areas of China. The aim of this study is to investigate the status and carcinogenic role of the point mutation of p53 gene exon7 in hepatocellular carcinoma from Anhui Province, a non-HCC-prevalent area in China. METHODS: PCR PCR-SSCP and PCR-RFLP were applied to analyze the homozygous deletion and point mutation of p53 exon7 in HCC samples from Anhui, which were confirmed by DNA sequencing and Genbank comparison. RESULTS: In the 38 samples of hepatocellular carcinoma, no homozygous deletion of p53 exon7 was detected and point mutations of p53 exon7 were found in 4 cases, which were found to be heterozygous mutation of codon 249 with a mutation rate of 10.53%(4/38). The third base mutation(G-T) of p53 codon 249 was found by DNA sequencing and Genbank comparison. CONCLUSION: The incidence of point mutation of p53 codon 249 is lower in hepatocellular carcinoma and the heterozygous mutation of p53 exon7 found in these patients only indicate that they have genetic susceptibility to HCC. p53 codon 249 is a hotspot of p53 exon7 point mutation, suggesting that the point mutation of p53 exon 7 may not play a major role in the carcinogenesis of HCC in Anhui Province, a non-HCC-prevalent area in China.
基金Supported by Administrative Department of Science and Innovation of the Republic of Colombia-COLCIENCIAS,No.RC-1106-408-20549Institución Universitaria Escuela Nacional del DeporteRegistro Poblacional de Cáncer de Cali,Universidad del Valle,Cali,Colombia
文摘AIM To characterize punctual mutations in 23S rRNA gene of clarithromycin-resistant Helicobacter pylori(H.pylori)and determine their association with therapeutic failure.METHODS PCR products of 23S rRNA gene V domain of 74 H.pylori isolates;34 resistant to clarithromycin(29 from a low-risk gastric cancer(GC)population:TumacoColombia,and 5 from a high-risk population:TuquerresColombia)and 40 from a susceptible population(28 from Tumaco and 12 from Túquerres)were sequenced using capillary electrophoresis.The concordance between mutations of V domain 23S rRNA gene of H.pylori and therapeutic failure was determined using the Kappa coefficient and Mc Nemar's test was performed to determine the relationship between H.pylori mutationsand clarithromycin resistance.RESULTS23S rRNA gene from H.pylori was amplified in 56/74 isolates,of which 25 were resistant to clarithromycin(20 from Tumaco and 5 from Túquerres,respectively).In 17 resistant isolates(13 from Tumaco and 4 from Túquerres)the following mutations were found:A1593 T1,A1653 G2,C1770 T,C1954 T1,and G1827 C in isolates from Tumaco,and A2144 G from Túquerres.The mutations T2183 C,A2144 G and C2196 T in H.pylori isolates resistant to clarithromycin from Colombia are reported for the first time.No association between the H.pylori mutations and in vitro clarithromycin resistance was found.However,therapeutic failure of eradication treatment was associated with mutations of 23S rRNA gene in clarithromycin-resistant H.pylori(κ=0.71).CONCLUSION The therapeutic failure of eradication treatment in the two populations from Colombia was associated with mutations of the 23S rRNA gene in clarithromycinresistant H.pylori.
基金supported by the Ministry of Science and Technology of China (2014CB964803 and 2015AA020307)the National Natural Science Foundation of China (Nos. 31530048, 31601163 and 81672117)+1 种基金he Chinese Academy of Sciences (XDB19010204 and QYZDJ-SSW-SMC023)the Shanghai Municipal Commission for Science and Technology(16JC1420500, 17JC1400900 and 17140901500)
文摘Generation of mouse models carrying a defined point mutation,especially disease-related point mutations,is of considerable interest for research in biology and medicine.The standard method based on embryonic stem cell（ESC）-mediated homologous recombination（HR）is time-and labor-consuming.
