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A novel splice site mutation of CRYBA3/A 1 gene associated with congenital cataract in a Chinese family 被引量:2
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作者 Meng-Han Wu Yin-Hui Yu +2 位作者 Qin-Long Hao Xiao-Hua Gong Ke Yao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第1期1-5,共5页
AIM: To identify the disease-causing mutation responsible for the presence of congenital cataract in a Chinese family. METHODS: The study recruited a four-generation Chinese pedigree affected by autosomal dominant c... AIM: To identify the disease-causing mutation responsible for the presence of congenital cataract in a Chinese family. METHODS: The study recruited a four-generation Chinese pedigree affected by autosomal dominant congenital cataract (ADCC). Family history and the history of cataract extraction were recorded. Blood samples were collected from individuals for DNA extraction. Direct sequencing of congenital cataract-associated genes was performed. Single-strand conformational polymorphism and bioinformatic analysis were conducted to further study the mutation. RESULTS: Direct sequencing revealed a novel splice site mutation of c.30-2 A〉G in the CRYBA3/A1 gene. The mutation co-segregated within all affected individuals in the family and was not found in unaffected members or 100 unrelated normal controls. These results were further confirmed by single-strand conformational polymorphism and bioinformatic analysis using the Human Splicing Finder and MaxEnt online software and Annovar computer software. CONCLUSION: c,30-2 A〉G mutation of CRYBA3/A1 gene is a novel mutation and broadens the genetic spectrum of ADCC, KEYWORDS: splice site mutation; congenital cataract; CRYBA3/A1 gene 展开更多
关键词 splice site mutation congenital cataract CRYBA3/A1 gene
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Congenital nephrogenic diabetes insipidus arginine vasopressin receptor 2 gene mutation at new site:A case report
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作者 Lu-Lu Yang Yan Xu +3 位作者 Jian-Li Qiu Qian-Yi Zhao Man-Man Li Hui Shi 《World Journal of Clinical Cases》 SCIE 2022年第36期13443-13450,共8页
BACKGROUND Congenital nephrogenic diabetes insipidus(CNDI)is a rare hereditary disorder.It is associated with mutations in the arginine vasopressin receptor 2(AVPR2)gene and aquaporin 2(AQP2)gene,and approximately 270... BACKGROUND Congenital nephrogenic diabetes insipidus(CNDI)is a rare hereditary disorder.It is associated with mutations in the arginine vasopressin receptor 2(AVPR2)gene and aquaporin 2(AQP2)gene,and approximately 270 different mutation sites have been reported for AVPR2.Therefore,new mutations and new manifestations are crucial to complement the clinical deficiencies in the diagnosis of this disease.We report a case of a novel AVPR2 gene mutation locus and a new clinical manifestation.CASE SUMMARY We describe the case of a 48-d-old boy who presented with recurrent fever and diarrhea 5 d after birth.Laboratory tests showed electrolyte disturbances and low urine specific gravity,and imaging tests showed no abnormalities.Genetic testing revealed a novel X-linked recessive missense mutation,c.283(exon 2)C>T(p.P95S).This mutation results in the substitution of a proline residue with a serine residue in the AVPR2 protein sequence.The diagnosis of CNDI was confirmed based on the AVPR2 gene mutation.The treatment strategy for this patient was divided into two stages,including physical cooling supplemented with appropriate amounts of water in the early stage and oral hydrochlorothiazide(1-2 mg/kg)after a clear diagnosis.After follow-up of one and a half years,the patient gradually improved.CONCLUSION AVPR2 gene mutations in new loci and new clinical symptoms help clinicians understand this disease and shorten the diagnosis cycle. 展开更多
关键词 Congenital nephrogenic diabetes insipidus Arginine vasopressin receptor 2 gene mutation New site DIARRHEA Case report
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Rapid Detection of rpoB Gene Mutations in Rif-resistant M.tuberculosis Isolates by Oligonucleotide Microarray 被引量:8
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作者 AI-HUA SUN XING-LI FAN +3 位作者 LI-WEI LI LI-FANG WANG WEN-YING AN JIE YAN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2009年第3期253-258,共6页
Objective To detect the specific mutations in rpoB gene of Mycobacterium tuberculosis by oligonucleotide microarray. Methods Four wild-type and 8 mutant probes were used to detect rifampin resistant strains. Target DN... Objective To detect the specific mutations in rpoB gene of Mycobacterium tuberculosis by oligonucleotide microarray. Methods Four wild-type and 8 mutant probes were used to detect rifampin resistant strains. Target DNA of M. tuberculosis was amplified by PCR, hybridized and scanned. Direct sequencing was performed to verify the results of oligonucleotide microarray Results Of the 102 rifampin-resistant strains 98 (96.1%) had mutations in the rpoB genes. Conclusion Oligonucleotide microarray with mutation-specific probes is a reliable and useful tool for the rapid and accurate diagnosis of rifampin resistance in M. tuberculosis isolates. 展开更多
关键词 Mycobacterium tuberculosis Rifampin resistance rpoB gene / site mutation Oligonucleotide microarray/detection
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Bilateral papilledema caused by chronic infantile neurological cutaneous and articular syndrome in a child with a novel (p. D305N) mutation in NLRP3 gene: a case report 被引量:1
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作者 Li Li Huanfen Zhou +4 位作者 Wei Shi Xiaotun Ren Xiaohua Tan Lirong Tian Chunxia Peng 《Annals of Eye Science》 2021年第3期80-88,共9页
The rare disease of chronic infantile neurological cutaneous and articular(CINCA)syndrome,is caused by the over-secretion of interleukin(IL)-1βdue to a gain-of-function NLRP3 gene mutation in the autosomal chromosome... The rare disease of chronic infantile neurological cutaneous and articular(CINCA)syndrome,is caused by the over-secretion of interleukin(IL)-1βdue to a gain-of-function NLRP3 gene mutation in the autosomal chromosome which often involves in eyes.In this report,we studied a 9-year-old girl with CINCA.The eyes were also involved and presented bilateral papilledema.Genetic testing revealed that the symptoms were caused by a novel gene mutation site(c.913G>A,p.D305N)in conservative domain exon-3 of NLRP3 which is gain-function gene of CINCA.The patient had the characteristic facial features,frontal fossa and saddle nose,manifested the generalized urticaria-like skin rash at two weeks after birth,periodic fever 6 months after birth,sensorineural deafness at 7 years old,and bilateral papilledema,aseptic meningitis and knee arthropathy at 9 years old.White cell counts,C-reactive protein increased and intracranial pressure raised to 300 mmH2O.The meningeal thickening enhanced by gadolinium in magnetic resonance imaging(MRI).Based on clinical features and genetic test,the girl was diagnosed bilateral papilledema secondary to CINCA and administered prednisone and lowered intracranial pressure medicine to resolve symptoms.With 3-year follow-up,patient had no inflammatory flare-up with visual acuity improvement.The finding of novel genetic mutation site(p.D305N)in NLRP3 gene expanded genotype spectrum associated with CINCA.This case also expanded the cause spectrum of papilledema and it highlighted systemic disease history for patients with bilateral papilledema. 展开更多
关键词 PAPILLEDEMA chronic infantile neurological cutaneous and articular syndrome(CINCA syndrome) novel genetic mutation site IL-1 blockage agent
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Mutation-induced spatial differences in neuraminidase structure and sensitivity to neuraminidase inhibitors
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作者 杨志伟 郝东晓 +3 位作者 车一卓 杨嘉辉 张磊 张胜利 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第1期145-153,共9页
Neuraminidase (NA), a major surface glycoprotein of influenza virus with well-defined active sites, is an ideal plat- form for the development of antiviral drugs. However, a growing number of NA mutations have drug ... Neuraminidase (NA), a major surface glycoprotein of influenza virus with well-defined active sites, is an ideal plat- form for the development of antiviral drugs. However, a growing number of NA mutations have drug resistance to today's inhibitors. Numerous efforts are made to explore the resistance mechanisms through understanding the structural changes in mutated NA proteins and the associated different binding profiles of inhibitors, via x-ray, nuclear magnetic resonance, electron microscopy, and molecular dynamics methods. This review presents the architectural features of mutated NA proteins, as well as the respective inhibitor sensitivities arising from these spatial differences. Finally, we summarize the resistance mechanisms of today's neuraminidase inhibitors and the outlook tbr the development of novel inhibitors. 展开更多
关键词 mutation active sites NEURAMINIDASE inhibitor sensitivity
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A novel splice mutation of HERG in a Chinese family with long QT syndrome
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作者 尚云鹏 谢旭东 +4 位作者 王兴祥 陈君柱 朱建华 陶谦民 郑良荣 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2005年第7期626-630,共5页
Congenital long QT syndrome (LQTS) is a genetically heterogeneous disease in which six ion-channel genes have been identified. The phenotype-genotype relationships of the HERG (human ether-a-go-go-related gene) mutati... Congenital long QT syndrome (LQTS) is a genetically heterogeneous disease in which six ion-channel genes have been identified. The phenotype-genotype relationships of the HERG (human ether-a-go-go-related gene) mutations are not fully understood. The objective of this study is to identify the underlying genetic basis of a Chinese family with LQTS and to characterize the clinical manifestations properties of the mutation. Single strand conformation polymorphism (SSCP) analyses were conducted on DNA fragments amplified by polymerase chain reaction from five LQT-related genes. Aberrant conformers were analyzed by DNA sequencing. A novel splice mutation in C-terminus of HERG was identified in this Chinese LQTS family,leading to the deletion of 11-bp at the acceptor splice site of Exon9 [Exon9 IVS del (-12→-2)]. The mutation might affect,through deficient splicing, the putative cyclic nucleotide binding domain (CNBD) of the HERG K+ channel. This mutation resulted in a mildly affected phenotype. Only the proband had a history of syncopes, while the other three individuals with long QT interval had no symptoms. Two other mutation carriers displayed normal phenotype. No sudden death occurred in the family. The 4 affected individuals and the two silent mutation carriers were all heterozygous for the mutation. It is the first splice mutation of HERG reported in Chinese LQTS families. Clinical data suggest that the CNBD mutation may be less malignant than mutations occurring in the pore region and be partially dominant over wild-type function. 展开更多
关键词 HERG gene Long QT syndrome Cardiac arrhythmia C-TERMINUS Acceptor splice site mutation
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Detection of a novel panel of 24 genes with high frequencies of mutation in gastric cancer based on next-generation sequencing
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作者 Hui-Hui Zeng Ze Yang +3 位作者 Ye-Bei Qiu Shoaib Bashir Yin Li Meng Xu 《World Journal of Clinical Cases》 SCIE 2022年第15期4761-4775,共15页
BACKGROUND Gastric cancer is a leading cause of cancer-related mortality worldwide.Many somatic mutations have been identified based on next-generation sequencing;they likely play a vital role in cancer treatment sele... BACKGROUND Gastric cancer is a leading cause of cancer-related mortality worldwide.Many somatic mutations have been identified based on next-generation sequencing;they likely play a vital role in cancer treatment selection.However,nextgeneration sequencing has not been widely used to diagnose and treat gastric cancer in the clinic.AIM To test the mutant gene frequency as a guide for molecular diagnosis and personalized therapy in gastric cancer by use of next-generation sequencing.METHODS We constructed a panel of 24 mutant genes to detect somatic nucleotide variations and copy number variations based on a next-generation sequencing technique.Our custom panel included high-mutation frequency cancer driver and tumour suppressor genes.Mutated genes were also analyzed using the cBioPortal database.The clinical annotation of important variant mutation sites was evaluated in the ClinVar database.We searched for candidate drugs for targeted therapy and immunotherapy from the OncoKB database.RESULTS In our study,the top 16 frequently mutated genes were TP53(58%),ERBB2(28%),BRCA2(23%),NF1(19%),PIK3CA(14%),ATR(14%),MSH2(12%),FBXW7(12%),BMPR1A(12%),ERBB3(11%),ATM(9%),FGFR2(8%),MET(8%),PTEN(6%),CHD4(6%),and KRAS(5%).TP53 is a commonly mutated gene in gastric cancer and has a similar frequency to that in the cBioPortal database.33 gastric cancer patients(51.6%)with microsatellite stability and eight patients(12.5%)with microsatellite instability-high were investigated.Enrichment analyses demonstrated that high-frequency mutated genes had transmembrane receptor protein kinase activity.We discovered that BRCA2,PIK3CA,and FGFR2 gene mutations represent promising biomarkers in gastric cancer.CONCLUSION We developed a powerful panel of 24 genes with high frequencies of mutation that could detect common somatic mutations.The observed mutations provide potential targets for the clinical treatment of gastric cancer. 展开更多
关键词 Gastric cancer Next-generation sequencing mutated genes Target sites Microsatellite instability
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Somatic TP53 mutations and comparison of different TP53 functional domains in human cancers:data analysis from the IARC TP53 database and the National Cancer Institute GDC data portal
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作者 Juan Du Hong-Jian Gong Han Xiao 《Medical Data Mining》 2021年第1期10-19,共10页
P53 gene mutations have been known to be highly related to the majority of human cancers.The colocation of biologists and bioinformaticians have constructed many databases for cancer research.Although the relationship... P53 gene mutations have been known to be highly related to the majority of human cancers.The colocation of biologists and bioinformaticians have constructed many databases for cancer research.Although the relationship between the presence of TP53 mutation and cancers has been reported in various studies,few reports TP53 mutation distribution in different functional domains.Hence,we use 2 databases(The TP53 Mutation Database of the International Agency for the Research on Cancer and The Genomic Data Commons data portal)to compare survival rate with and without TP53 mutations in a certain cancer,as well as to find most frequent mutation sites in different functional domains of the TP53 protein.Our study shows that most somatic mutations of TP53 and high mutation rate sites are concentrated in the DNA-binding domain,and the survival of certain cancers varies with and without P53. 展开更多
关键词 Somatic mutations TP53 domains mutation distribution Tumor site distribution
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RAD51基因突变的首诊卵巢癌患者真实患病体验质性研究
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作者 陶渝 陶帅 王晓川 《中国计划生育学杂志》 2024年第1期10-14,共5页
目的:了解DNA重组修复基因(RAD51)突变的首诊卵巢癌(OC)患者真实患病体验,为后续制定干预措施提供理论依据.方法:采用目的抽样的方法抽取2022年1-12月在北京市某三级甲等医院妇科收治的RAD51基因突变、未开展治疗的OC患者作为研究对象,... 目的:了解DNA重组修复基因(RAD51)突变的首诊卵巢癌(OC)患者真实患病体验,为后续制定干预措施提供理论依据.方法:采用目的抽样的方法抽取2022年1-12月在北京市某三级甲等医院妇科收治的RAD51基因突变、未开展治疗的OC患者作为研究对象,采用现象学方法进行半结构化访谈并现场录音,应用Colaizzi现象学7步分析法对访谈资料进行分析、提炼主题.结果:本研究归纳提炼出3个主题,即积极与消极并存、希望专业指导和行为观念转变.RAD51基因突变OC患者存在明显的负性情绪,也有积极心态养成的趋势,存在自我行为观念转变,有意愿监督易感亲属行为,对OC的认知程度较低,希望得到专业指导.结论:RAD51基因突变OC患者存在负性情绪及认知不足的情况,医护人员应及时关注RAD51基因突变OC患者的负性情绪,促进其积极心态的养成,纠正患者的不良认知.医疗机构应尽早构建OC基因检测咨询体系,为患者提供专业基因检测后续指导. 展开更多
关键词 卵巢癌 DNA重组修复基因 基因突变 患病体验 质性研究
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线粒体DNA含量及10398位点在健康及宫颈癌人群中的分析
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作者 丰大利 张丽瑾 黄华忠 《中国现代医生》 2024年第21期86-89,共4页
目的探讨血清中线粒体DNA(mitochondrial DNA,mtDNA)含量和10398位点突变情况检测的临床意义。方法收集2020年1月至12月在宜昌市第二人民医院体检的314名健康女性纳入健康体检组,同时收集2020年1月至2023年12月在宜昌市第二人民医院就诊... 目的探讨血清中线粒体DNA(mitochondrial DNA,mtDNA)含量和10398位点突变情况检测的临床意义。方法收集2020年1月至12月在宜昌市第二人民医院体检的314名健康女性纳入健康体检组,同时收集2020年1月至2023年12月在宜昌市第二人民医院就诊的82例宫颈癌患者纳入宫颈癌组。检测两组纳入者的血清样本mtDNA含量及10398位点基因型,并比较两组纳入者的指标差异。结果宫颈癌组患者的mtDNA含量高于健康体检组,差异有统计学意义(P<0.05);两组纳入者在10398位点基因型差异无统计学意义(P>0.05)。健康体检组中≥45岁的女性mtDNA含量更高,差异有统计学意义(P<0.05);mtDNA在不同10398位点的分布差异无统计学意义(P>0.05)。宫颈癌组中≥45岁的患者mtDNA含量更高,差异有统计学意义(P<0.05);不同临床分期、不同病理类型患者的mtDNA含量差异无统计学意义(P>0.05),mtDNA在不同10398位点中的含量差异无统计学意义(P>0.05)。结论mtDNA含量检测对健康体检人群与宫颈癌人群均有一定的意义,两组纳入者的mtDNA含量均与年龄相关,均随着年龄增长而升高;宫颈癌患者的mtDNA含量明显高于健康体检者;10398位点的血清mtDNA含量检测对两组人群的意义不大;宫颈癌人群的mtDNA含量及10398位点分布与病理、临床分期均无关。mtDNA含量检测可考虑作为宫颈癌诊断的血清标志物。 展开更多
关键词 线粒体DNA 10398位点突变 宫颈癌 健康人群
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猪瘟病毒C株表位突变毒株的构建及拯救
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作者 刘元杰 徐璐 +9 位作者 朱元源 徐嫄 张乾义 李翠 李明 夏应菊 王琴 刘业兵 赵启祖 邹兴启 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第2期698-705,共8页
本研究旨在突变猪瘟病毒C株WH303位点,构建感染性克隆,为猪瘟病毒C株标记疫苗的研究提供候选毒株。本试验以猪瘟病毒C株为研究材料,经重叠PCR方法突变WH303位点,再分别连接至C株和C-flag株全长感染性克隆。体外转录RNA,转染PK15细胞,细... 本研究旨在突变猪瘟病毒C株WH303位点,构建感染性克隆,为猪瘟病毒C株标记疫苗的研究提供候选毒株。本试验以猪瘟病毒C株为研究材料,经重叠PCR方法突变WH303位点,再分别连接至C株和C-flag株全长感染性克隆。体外转录RNA,转染PK15细胞,细胞连续传代完成病毒的拯救和增殖。结果显示,经特异性限制内切酶酶切反应验证,感染性克隆构建成功。经RT-PCR、过氧化物酶单层细胞试验检测,表明病毒成功拯救。病毒细胞传代至17代,检测到病毒,表明病毒可以稳定传代。综上,本研究成功构建了C株WH303突变感染性克隆MC和MC-flag,并成功拯救MC株,得到可以稳定传代的病毒株。 展开更多
关键词 猪瘟病毒 C株 WH303位点 突变 感染性克隆
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影响H9N2亚型禽流感病毒生物学特性的关键氨基酸位点分析
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作者 周婉婷 彭程 +3 位作者 蒋文明 宋厚辉 刘朔 刘华雷 《中国动物检疫》 CAS 2024年第8期20-27,共8页
H9N2亚型禽流感病毒是在我国家禽中流行最为广泛的亚型,严重影响养禽业健康发展,具有感染哺乳动物的能力。可感染人类的H5N1、H7N9、H10N8和H3N8等新型流感病毒中多次发现H9N2亚型禽流感病毒的内部基因,而这些感染人类的新型流感病毒对... H9N2亚型禽流感病毒是在我国家禽中流行最为广泛的亚型,严重影响养禽业健康发展,具有感染哺乳动物的能力。可感染人类的H5N1、H7N9、H10N8和H3N8等新型流感病毒中多次发现H9N2亚型禽流感病毒的内部基因,而这些感染人类的新型流感病毒对公共卫生安全造成了巨大威胁。文章围绕H9N2亚型禽流感病毒,总结了影响该亚型病毒致病性、受体结合、复制能力以及在家禽或哺乳动物中与传播有关的关键功能氨基酸位点突变的研究进展,以期进一步解析H9N2亚型禽流感病毒及其内部基因在新型流感病毒产生过程中的机制和作用。 展开更多
关键词 禽流感病毒 H9N2 氨基酸位点 生物学特性 突变
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定向引入N⁃糖基化位点促进芳基醇氧化酶热稳定性及底物亲和力
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作者 曹查 朱作华 +3 位作者 龚文兵 周映君 谢纯良 彭源德 《食品研究与开发》 CAS 2024年第7期165-173,共9页
芳基醇氧化酶在木质素降解过程中发挥重要作用,N-糖基化修饰影响其酶学性质。该文旨在通过研究刺芹侧耳(Pleurotus eryngii)来源的芳基醇氧化酶N-糖基化,来提高其热稳定性和底物亲和力。利用毕赤酵母GS115表达系统和定点突变技术,构建表... 芳基醇氧化酶在木质素降解过程中发挥重要作用,N-糖基化修饰影响其酶学性质。该文旨在通过研究刺芹侧耳(Pleurotus eryngii)来源的芳基醇氧化酶N-糖基化,来提高其热稳定性和底物亲和力。利用毕赤酵母GS115表达系统和定点突变技术,构建表达6种芳基醇氧化酶突变体蛋白,并对纯化后的野生型和突变体酶进行酶学性质和热稳定性分析。结果表明,芳基醇氧化酶N89和N249糖基化位点突变导致最适温度和70℃时酶热稳定性降低;在这个过程中,将其引入新的糖基化位点后的突变体,其最适酸碱度没有变化,最适温度以及70℃下的热稳定程度都明显优于野生型;以藜芦醇为底物时,突变体[AAO(F-X-N-X-T)]与底物亲和力最高。N-糖基化主要影响芳醇氧化酶的热稳定性,其中N89和N249位点的N-糖基化对酶的热稳定性起重要作用;引入N-糖基化位点[AAO(F-X-N-X-T)]能获得具有高活力和高稳定性的芳醇氧化酶。 展开更多
关键词 芳基醇氧化酶 N-糖基化 定点突变 重组表达 酶学性质
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麦芽糖酶-葡萄糖淀粉酶D246A异源表达及性质表征
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作者 高雨晴 董钢印 +3 位作者 张洪瑞 马占山 方丽 詹冬玲 《吉林大学学报(理学版)》 CAS 北大核心 2024年第3期742-749,共8页
以大型真菌灵芝中的麦芽糖酶-葡萄糖淀粉酶(MGAM)为研究对象,采用同源序列比对、同源模建、底物对接和定点突变等方法成功构建酶活力显著降低的突变体D246A.酶学性质表征结果表明:最适反应温度由野生型(wild type,WT)的65℃减少至60℃,... 以大型真菌灵芝中的麦芽糖酶-葡萄糖淀粉酶(MGAM)为研究对象,采用同源序列比对、同源模建、底物对接和定点突变等方法成功构建酶活力显著降低的突变体D246A.酶学性质表征结果表明:最适反应温度由野生型(wild type,WT)的65℃减少至60℃,突变体耐热能力下降;最适pH值由WT的6.0升高至7.0,有利于工程菌生长;半衰期由WT的2.0 h下降至1.5 h,酶稳定性降低.酶动力学结果表明:突变体D246A酶动力学曲线符合Michaelis方程,与WT相比,K_(m)值变大,表明酶与底物亲和力下降;V_(max)约降低至原来的1/4. 展开更多
关键词 定点突变 异源表达 性质表征 麦芽糖酶-葡萄糖淀粉酶
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用于降解邻苯二甲酸酯的红球菌来源酰胺酶RhoⅡ突变改造
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作者 黄慧芹 徐友强 +2 位作者 李微微 张成楠 李秀婷 《食品科学技术学报》 EI CAS CSCD 北大核心 2024年第4期125-134,共10页
邻苯二甲酸酯(phthalate esters,PAEs)具有生理毒性,去除毒性的关键在于侧链酯键的完全水解。红球菌源酰胺酶RhoⅡ是作用于邻苯二甲酸单酯酯键的水解酶,但不能水解PAEs。采用计算机模拟和定点突变的方法,对RhoⅡ进行改造,以实现水解PAE... 邻苯二甲酸酯(phthalate esters,PAEs)具有生理毒性,去除毒性的关键在于侧链酯键的完全水解。红球菌源酰胺酶RhoⅡ是作用于邻苯二甲酸单酯酯键的水解酶,但不能水解PAEs。采用计算机模拟和定点突变的方法,对RhoⅡ进行改造,以实现水解PAEs的目的。将RhoⅡ与邻苯二甲酸单丁酯(monobutyl phthalate,MBP)进行分子对接,结果显示,RhoⅡ以Lys200、Arg185的R基稳定MBP的羧基,MBP与RhoⅡ的两个单体均形成氢键相互作用。位点突变表明,Asp39、Lys127和Cys160构成了RhoⅡ的催化三联体,作为活性中心存在于酶的疏水凹槽内。此外,通过定点突变获得了具有水解PAEs的突变酶F44N,与原酶相比,其水解邻苯二甲酸二丁酯(dibutyl phthalate,DBP)、邻苯二甲酸二异丁酯(diisobutyl phthalate,DIBP)的能力显著提升,这是由于苯丙氨酸突变为天门冬酰胺后,明显削弱了酶对底物的空间位阻作用,使酶的底物结合空腔体积增大,DBP、DIBP能够与酶进行结合,实现酯键水解。结合突变前后对接结果推测,突变影响酶的底物结合空腔,导致突变酶不能有效催化邻苯二甲酸单酯。通过验证RhoⅡ的催化活性中心,突变关键位点,实现了RhoⅡ底物谱的改变,希望可以丰富催化水解PAEs的酶资源,促进相关水解酶更好的应用。 展开更多
关键词 酰胺水解酶 邻苯二甲酸单酯 分子对接 催化三联体 定点突变
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杂草对除草剂抗性机理研究进展
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作者 张玲玲 徐凡 +2 位作者 李嘉文 陈芷莹 郑明奇 《农药学学报》 CAS CSCD 北大核心 2024年第4期703-715,共13页
随着除草剂持续、广泛地使用,杂草的抗性不断增强,新的抗性机理不断被发现。本文总结了近10年来杂草在靶标抗性(target-site resistance,TSR)和非靶标抗性(non-target-site resistance,NTSR)机理方面的重要研究进展。TSR机理主要包括乙... 随着除草剂持续、广泛地使用,杂草的抗性不断增强,新的抗性机理不断被发现。本文总结了近10年来杂草在靶标抗性(target-site resistance,TSR)和非靶标抗性(non-target-site resistance,NTSR)机理方面的重要研究进展。TSR机理主要包括乙酰乳酸合成酶、乙酰辅酶A羧化酶和5-烯醇丙酮酰莽酸-3-磷酸合酶等多个除草剂靶标酶上发生的新抗性突变,以及应对更强除草剂选择压力的靶标酶多位点突变和多靶标同工酶突变等。此外,本文也针对细胞色素P450(CYP81)酶、醛酮还原酶和ABC转运蛋白(EcABCC8)等NTSR机理在对草甘膦抗性中的作用进行了详细描述。本文不仅有助于全面、深入理解杂草抗性分子机理和抗性进化规律,在科学使用除草剂和创制新作用机理的除草剂等方面也具有一定的启示作用。 展开更多
关键词 杂草 除草剂 靶标抗性 非靶标抗性 抗性突变 细胞色素P450
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一种筛选水稻Mutmap+突变位点的简易方法
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作者 王延妍 李颖颖 +4 位作者 王子瑞 毛馨晨 唐家琪 于恒秀 张超 《扬州大学学报(农业与生命科学版)》 CAS 北大核心 2024年第1期27-32,共6页
利用基因组重测序技术进行基因定位目前已在水稻功能基因组学研究中得到广泛应用。其中,Mutmap+技术因无需进行杂交操作,且无需背景亲本的基因组信息,具有更广阔的应用前景。然而,目前Mutmap+技术筛选候选突变位点的方法依赖于复杂的数... 利用基因组重测序技术进行基因定位目前已在水稻功能基因组学研究中得到广泛应用。其中,Mutmap+技术因无需进行杂交操作,且无需背景亲本的基因组信息,具有更广阔的应用前景。然而,目前Mutmap+技术筛选候选突变位点的方法依赖于复杂的数据计算,要求研究者具有较高的生物信息学知识。根据Mutmap+的实验原理,设计一种简单的筛选候选突变位点的方法。该方法对混池测序的表型池与非表型池的突变指数分别加以限定,即表型池突变指数等于1,非表型池突变指数小于0.5。对测序所得突变位点进行简单排序,即可得到候选突变位点。运用该筛选方法,从6个水稻不育突变体成功克隆突变基因,并对其中1个突变体进行了细胞学表型的验证。该方法可简化Mutmap+技术的数据分析流程,便于将Mutmap+技术更好地运用到水稻功能基因组学研究中。 展开更多
关键词 水稻 Mutmap+ 突变位点筛选 基因克隆
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乳腺癌核仁磷蛋白乙酰化及其修饰位点突变体的构建和表达
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作者 郝经伟 潘婷 +6 位作者 李月 朱文斌 段文博 刘立琨 岳丽玲 刘云龙 高秀丽 《解剖学报》 CAS CSCD 2024年第2期196-202,共7页
目的明确女性乳腺癌中核仁磷蛋白(NPM)乙酰化修饰水平,并通过修饰位点突变体的构建探讨其功能。方法蛋白质修饰组学方法检测对比人乳腺癌组织及癌旁正常组织(各3例)NPM乙酰化水平及乙酰化位点;基因定点突变PCR构建NPM乙酰化突变体,限制... 目的明确女性乳腺癌中核仁磷蛋白(NPM)乙酰化修饰水平,并通过修饰位点突变体的构建探讨其功能。方法蛋白质修饰组学方法检测对比人乳腺癌组织及癌旁正常组织(各3例)NPM乙酰化水平及乙酰化位点;基因定点突变PCR构建NPM乙酰化突变体,限制性内切酶(DpnI)消化及大肠埃希菌转化获得特异性突变体重组质粒;双酶切与测序验证各突变体序列准确性;瞬时转染及RT-PCR方法检测各突变体过表达效果。Western blotting验证NPM乙酰化水平,蛋白质定量组学及生物信息学分析NPM乙酰化功能。结果乳腺癌组织样本中NPM第27及第32位赖氨酸乙酰化水平分别为癌旁正常组织的2.76及2.22倍;构建的NPM乙酰化位点突变体与野生型NPM分子量一致且出现预期突变位点;转染NPM各突变体的BT-549细胞相应NPM mRNA表达水平明显升高。随着野生型NPM表达水平增加,蛋白乙酰化水平增加,27位赖氨酸发生负向突变后,修饰水平下降。NPM乙酰化可使BT-549细胞中101种蛋白表达水平发生明显变化,上述蛋白在细胞大分子生物合成,以DNA为模板的转录过程,RNA生物合成以及RNA代谢过程中富集。结论乳腺癌NPM呈高乙酰化水平并可能在细胞大分子生物合成,转录过程,RNA生物合成以及RNA代谢过程中发挥关键功能。 展开更多
关键词 乳腺癌 核仁磷蛋白乙酰化 定点突变 蛋白质组学
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枯草芽孢杆菌YvdSR蛋白转运Na^(+)关键残基的研究
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作者 张凌霄 张正来 +1 位作者 郑秀桃 姜巨全 《东北农业大学学报》 CAS CSCD 北大核心 2024年第5期56-64,共9页
对枯草芽孢杆菌(Bacillus subtilis strain 168)双组分基因YvdSR表达的双组分蛋白YvdSR进行功能鉴定,得出YvdSR具有转运Na^(+)/Li^(+)功能,为探究YvdSR离子转运机制,分别对两种组分作同源序列比对,从每种组分中筛选出完全保守的酸性氨... 对枯草芽孢杆菌(Bacillus subtilis strain 168)双组分基因YvdSR表达的双组分蛋白YvdSR进行功能鉴定,得出YvdSR具有转运Na^(+)/Li^(+)功能,为探究YvdSR离子转运机制,分别对两种组分作同源序列比对,从每种组分中筛选出完全保守的酸性氨基酸残基并进行氨基酸残基定点突变。结果表明,YvdS和YvdR共有的E13在同源物中完全保守且突变为丙氨酸后均失去Na^(+)(Li^(+))/H^(+)逆向转运活性,说明两种组分的E13均是蛋白质行使功能不可或缺的,YvdS的E13A经回复突变后可恢复高水平Na^(+)(Li^(+))/H^(+)逆向转运活性,YvdR的E13A经回复突变后仍失去Na^(+)(Li^(+))/H^(+)逆向转运活性,表明YvdS和YvdR在Na^(+)(Li^(+))/H^(+)逆向转运中行使不同功能。 展开更多
关键词 Na^(+)/H^(+)逆向转运 YvdSR 膜蛋白 定点突变
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双乾肉羊PDK4基因的组织表达差异及多态性分析
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作者 缪立生 肖成 +7 位作者 杨少滢 栾祜 赵文军 沈宏旭 刘宇 曹阳 巩俊明 《黑龙江畜牧兽医》 CAS 北大核心 2024年第1期47-53,共7页
为了研究丙酮酸脱氢酶激酶4(pyruvate dehydrogenase kinase 4,PDK4)基因在双乾肉羊不同组织中的表达差异,以及基因外显子多态性对肉质性状的影响,试验以45只健康的8月龄双乾肉羊公羊为研究对象,屠宰后采集心脏、肝脏、脾脏、肺脏、肾... 为了研究丙酮酸脱氢酶激酶4(pyruvate dehydrogenase kinase 4,PDK4)基因在双乾肉羊不同组织中的表达差异,以及基因外显子多态性对肉质性状的影响,试验以45只健康的8月龄双乾肉羊公羊为研究对象,屠宰后采集心脏、肝脏、脾脏、肺脏、肾脏、十二指肠及背最长肌,利用PCR法与Sanger测序法结合的方式检测PDK4基因外显子中的单核苷酸多态性位点(SNP),并与肉质性状数据进行关联分析。结果表明:PDK4基因广泛分布于各组织中,在十二指肠组织中的相对表达量最高。PDK4基因第1外显子存在2个SNP位点,分别为Chr 4.14723148 T>C突变、Chr 4.14723208 T>C突变。Chr 4.14723148 T>C存在2种基因型,分别为CC和CT基因型;Chr 4.14723208 T>C存在3种基因型,分别是TT、TC和CC基因型。突变基因型分布符合哈代温伯格(Hardy-Weinberg)定律,突变个体在群体中处于稳定状态。Chr 4.14723148 T>C和Chr 4.14723208 T>C位点的多态性信息含量分别为0.94和0.61,均为高度多态(P>0.5),Chr 4.14723148 T>C突变中CC基因型为优势基因型,其个体压榨水分率显著低于CT基因型个体(P<0.05)。说明双乾肉羊群体稳定存在Chr 4.14723148突变位点,并且CC优势基因型个体肌肉水分保持能力更强,正向影响肉质性状。 展开更多
关键词 双乾肉羊 PDK4基因 突变位点 肉质性状 组织表达谱
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