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《河北农业大学学报》2021,44(1):114-119
对1株H7N9亚型禽流感毒株A/environment/Hebei/621/2017(H7N9)简称EN621进行基因测序和序列分析,研究其遗传进化趋势和分子生物学特征。结果显示,该毒株血凝素(Hemagglutinin,HA)和神经氨酸酶(Neuraminidase,NA)分别与人源流感毒株的HA和NA属于同一进化支进化而来,EN621毒株HA蛋白的裂解位点存在多个连续碱性氨基酸,符合典型高致病性AIV特征;HA蛋白上有4个糖基化位点与人源流感毒株HA蛋白糖基化位点一致,且第226位氨基酸为Q,优先与禽类α-2,3唾液酸受体结合;NA蛋白上有6个潜在糖基化位点与人源流感毒株NA蛋白糖基化位点一致;NP蛋白第184氨基酸位点由A突变为K,对于AIV的复制和致病性有着密切联系。本研究提示EN621毒株存在感染人的潜在可能性,应加强H7N9亚型禽流感病毒的监测,建立相应的防范机制,保障公共安全。 相似文献
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[目的]了解山东省猪流感病毒(Swine influenza virus,SIV)的流行状况及其进化趋势,为有效防控山东猪流感(Swine influenza,SI)提供理论依据.[方法]从山东各地疑似发生SI的猪群中采集猪鼻拭子,接种于10日龄SPF鸡胚,盲传3代后进行病毒分离、亚型鉴定,并对八片段基因进行克隆测序及遗传进化分析.[结果]从150份猪鼻拭子中分离得到一株SIV,命名为A/Swine/LXB/1016/2012,经鉴定属于H9N2亚型.A/Swine/LXB/1016/2012 (H9N2)毒株HA基因的裂解位点为VSSR/GL,无多个连续性碱基插入,属于低致病性流感病毒;而其受体结合位点与A/chicken/Heilongjiang/35/2000、A/duck/HK/168/1977、A/duck/HK/702/1979、A/duck/HK/Y439/1997、A/northernshoveler/Missouri/298/2009、A/swine/Korea/S452/2004和A/turkey/Wiaconsin/1966毒株一致,同时具有禽源流感病毒和猪源流感病毒的特征.遗传进化树分析结果也表明,A/Swine/LXB/1016/2012(H9N2)毒株与A/turkey/Wisconsin/1966、A/swine/Korea/S452/2004毒株的亲缘关系最近,可能来自相同的祖先.[结论]A/Swine/LXB/1016/2012毒株同时具有禽源流感和猪源流感的特征,推断该毒株是一株禽流感病毒向猪体适应的毒株. 相似文献
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[目的]明确广西鸡源H9N2亚型禽流感病毒(AIV)的分子遗传变异规律及其对公共卫生安全的影响,为H9亚型禽流感(AI)的防控提供参考依据.[方法]从广西某肉鸡养殖场采集病料,经SPF鸡胚接种进行病毒分离,对初步鉴定为H9亚型AIV分离株的HA、NA、PB2、PB1、PA、NP、M和NS等8个基因片段进行克隆测定及遗传进化分析,同时对分离毒株的生物学特性进行测定.[结果]从广西发病鸡群中分离获得一株H9N2亚型AIV,命名为A/chicken/Guangxi/BT1/2016(H9N2).分离毒株A/chicken/Guangxi/BT1/2016(H9N2)HA基因的裂解位点为PSRSSR↓GLF,具有典型的低致病性AIV(LPAIV)分子特征,在遗传进化关系上属于4.2.5分支,与国内常用H9N2亚型AIV疫苗株所属的4.2.3分支存在一定差异;其他7个基因也分别来源于不同的AIV亚型.分离毒株A/chicken/Guangxi/BT1/2016 (H9N2)同时具备与α-2,3唾液酸和α-2,6唾液酸受体结合的特性,且具有感染人类的潜在风险;其感染鸡群后病毒分布主要集中在气管、肺脏和脾脏,可通过呼吸道和消化道同时排毒,且在攻毒后第1d即开始排毒,第5d为排毒高峰.[结论]从广西发病鸡群中分离获得的A/chicken/Guangxi/BT1/2016(H9N2)属于LPAIV,是由不同亚型AIV重组产生的H9N2亚型新毒株,可导致鸡群疫苗免疫失败,且具有感染人类的潜在风险. 相似文献
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【目的】明确犬源H9N2亚型流感病毒的分子变异特征及致病性,为今后探究流感病毒的禽—犬跨种传播机制提供科学依据。【方法】从流浪犬中分离H9N2亚型流感病毒,利用RT-PCR扩增其8个基因节段进行BLAST同源比对,然后基于国内外的22株参考毒株进行遗传进化分析,并通过小鼠滴鼻感染试验评估分离毒株的致病性。【结果】从采集的393份犬鼻拭子样品中分离获得1株H9N2亚型流感病毒,命名为A/canine/Guangxi/LZ11/2018(简写为LZ11)。分离毒株LZ11为三重组毒株,其中,HA、NA和NS基因属于BJ/94类谱系,PB2和M基因属于G1类谱系,PB1、PA和NP基因属于F/98类谱系;病毒基因组成属于近年我国广泛流行的S基因型。分离毒株LZ11的HA蛋白在第324~331位存在1个裂解位点(PSRSSR↓GL),符合低致病性流感病毒的特征;HA蛋白还出现226Q→L突变,具有优先结合人类α-2,6唾液酸受体的能力;NA蛋白在119E、151D、276E、292R和... 相似文献
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Eighteen codons in the HA1 domain of the hemagglutinin genes of human influenza A subtype H3 appear to be under positive selection to change the amino acid they encode. Retrospective tests show that viral lineages undergoing the greatest number of mutations in the positively selected codons were the progenitors of future H3 lineages in 9 of 11 recent influenza seasons. Codons under positive selection were associated with antibody combining site A or B or the sialic acid receptor binding site. However, not all codons in these sites had predictive value. Monitoring new H3 isolates for additional changes in positively selected codons might help identify the most fit extant viral strains that arise during antigenic drift. 相似文献
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CHEN Hua-lan 《农业科学学报》2019,18(7):1419-1420
正Animal influenza viruses continuously circulate in their reservoirs in nature and pose severe threat to humans and animals; therefore, understanding and control of animal influenza viruses will have important implication to public 相似文献
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猪流行性感冒 ,当地俗称猪流感 ,是对养猪业危害较大的传染病之一。笔者根据临诊经验 ,总结出该病有三大特点 :一是高热 ,病初体温 39.5~ 40 .5℃ ,随后上升至41.5℃ ;二是反复发作 ,当停药 2 4h后 ,体温很快回升至41.5~ 42℃ ;三是病程较长 ,大部分病例需经治疗 2周左右 ,才能康复。1 流行情况该病对不同年龄、品种、性别的猪均可感染。一年四季均可发生。在信阳地区 ,该病的多发、高发期是夏季。这与有些资料报道多发于寒冷季节与早春不大相同 ,越是高温季节 ,越是该病的流行期 ,所以群众称之为“夏季热”病。该病有较强的传染性 ,同群… 相似文献
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为了解鸭源H4N6亚型禽流感病毒A/duck/Shanghai/Y20/2006(DK/SH/Y20/06)的来源、特征及其分子演化规律,进一步丰富水禽流感病毒的基因库,对该病毒8个基因片段分别进行了扩增和序列测定,利用分子生物学软件对测序结果进行序列分析,并与GenBank登录的相关病毒进行了遗传演化分析。结果表明,DK/SH/Y20/06的HA基因切割位点附近的氨基酸序列(PEKASR↓GLF)符合低致病力AIV的特征,其分子遗传演化关系属于欧亚分支;NA基因与A/mallard/Yanchen/2005(H4N6)在同一分支内,核苷酸序列同源性为98.3%;而PB2、PB1、NP、PA基因与目前在国内流行的H6亚型禽流感病毒关系密切;M基因与A/environment/Korea/CSM05/2004(H3N1)处于同一分支;而NS基因与A/wild duck/Korea/YS44/2004(H1N2)同源性最高。且DK/SH/Y20/06的8个基因与美洲H4N6亚型AIV分离株均不处在同一遗传进化分支上,相互之间遗传关系较远。可见,DK/SH/Y20/06可能是由H4N6、H6N2、H6N5、H3N1和H1N2等不同亚型来源的基因在鸭体内经过复杂重组演变的一株重组病毒。 相似文献
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In serums of unusually isolated Pacific islanders whose only exposure to influenza occurred during the era of the 1918 pandemic the residual neutralizing antibody was greatest to the PR/8 and BH strains of human type A influenza virus, significantly lower to swine influenza virus, and absent to equine or later human type A virus strains. The pandemic virus was thus antigenically closer to human type A strains isolated during the middle 1930's than to other known influenza virus types. 相似文献
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【目的】从分子生物学角度了解H9N2亚型禽流感病毒在湖南省洞庭湖区的变异特点和进化规律。【方法】对近年来洞庭湖区分离的12株H9N2亚型禽流感毒株的全基因进行分段克隆测序,应用Mega 5软件包对病毒基因进行多序列比对和进化树的绘制与分析。【结果】12株H9N2亚型禽流感毒株HA裂解位点均没有多个连续的碱性氨基酸插入,属于低致病性病毒。12株H9N2亚型禽流感病毒HA、NA基因进化比较同步,均处于DK/HK/Y280/97分支,而6个内部基因(M、PB2、PB1、PA、NA、NS)与高致病性禽流感H5亚型毒株呈现不同程度重组现象,且与H7N9亚型毒株基因的核苷酸同源性很高,很有可能为其提供内部基因。【结论】湖南省洞庭湖地区H9亚型禽流感病毒的遗传演化较为复杂,存在广泛的基因重组现象。 相似文献
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Tumpey TM Basler CF Aguilar PV Zeng H Solórzano A Swayne DE Cox NJ Katz JM Taubenberger JK Palese P García-Sastre A 《Science (New York, N.Y.)》2005,310(5745):77-80
The pandemic influenza virus of 1918-1919 killed an estimated 20 to 50 million people worldwide. With the recent availability of the complete 1918 influenza virus coding sequence, we used reverse genetics to generate an influenza virus bearing all eight gene segments of the pandemic virus to study the properties associated with its extraordinary virulence. In stark contrast to contemporary human influenza H1N1 viruses, the 1918 pandemic virus had the ability to replicate in the absence of trypsin, caused death in mice and embryonated chicken eggs, and displayed a high-growth phenotype in human bronchial epithelial cells. Moreover, the coordinated expression of the 1918 virus genes most certainly confers the unique high-virulence phenotype observed with this pandemic virus. 相似文献
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Pinheiro VB Taylor AI Cozens C Abramov M Renders M Zhang S Chaput JC Wengel J Peak-Chew SY McLaughlin SH Herdewijn P Holliger P 《Science (New York, N.Y.)》2012,336(6079):341-344
Genetic information storage and processing rely on just two polymers, DNA and RNA, yet whether their role reflects evolutionary history or fundamental functional constraints is currently unknown. With the use of polymerase evolution and design, we show that genetic information can be stored in and recovered from six alternative genetic polymers based on simple nucleic acid architectures not found in nature [xeno-nucleic acids (XNAs)]. We also select XNA aptamers, which bind their targets with high affinity and specificity, demonstrating that beyond heredity, specific XNAs have the capacity for Darwinian evolution and folding into defined structures. Thus, heredity and evolution, two hallmarks of life, are not limited to DNA and RNA but are likely to be emergent properties of polymers capable of information storage. 相似文献
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This paper comparatively analyzes the density of nucleotide sequences potentially predisposed to the formation of noncanonical DNA structures (G4 quadruplexes) on the hemagglutinin (HA) and neuraminidase (NA) genes of the avian influenza A virus (H5N1) and the env and pol genes of the bovine leucosis virus. The higher genetic heterogeneity of the HA gene in comparison with the NA gene coincided with the high frequency of the nucleotide sequences predisposed to the formation of G4 quadruplexes. The same tendency was observed when comparing the distribution of potential G4 quadruplexes in the env and pol genes of the bovine leucosis virus. We discuss a possible relation between the increased density of the noncanonical DNA structures in the genes whose products interact with the receptor system of target cells of a retrovirus infection and their genetic heterogeneity maintained in the host-pathogen system. 相似文献
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[目的]明确广西猪源H9N2亚型流感病毒的遗传特征及分子生物学特性(抗原性、耐药性和致病性),为广西猪源H9N2亚型流感病毒的防控提供科学依据.[方法]以分离自广西百色地区的2株猪源H9N2亚型流感病毒(SW/GX/P2/2011株和SW/GX/P3/2011株)为研究对象,运用RT-PCR扩增其全基因组的8个基因片段(HA、NA、NP、M、NS、PB1、PB2和PA基因),经克隆测序后进行核苷酸序列及氨基酸位点分析.[结果]2株广西猪源H9N2亚型流感病毒的核苷酸序列开放阅读框(ORF)分别是PB2:2280 bp、PB1:2274 bp、PA:2151 bp、HA:1683 bp、NP:1497 bp、NA:1410 bp、M:982 bp和NS:838 bp.2株广西猪源H9N2亚型流感病毒全基因组仅M基因核苷酸序列与猪源H9N2亚型流感病毒的相似性较高,而HA、NA、NP、NS、PA、PB2和PB1基因核苷酸序列均与禽源H9N2亚型流感病毒的相似性较高,在基因型分类上属于G57基因型,为我国广泛流行的H9N2亚型基因型.2株广西猪源H9N2亚型流感病毒的HA蛋白发生R180Q、T213A、D216E、M224L、N285S和V287T突变,NA蛋白抗原决定簇S331V、W403S和Q431K也发生突变;NA蛋白在N2亚型的耐药性关键位点119E、151D、292R、276E和294N位点未发生突变,但在NA蛋白抗原区存在S331V、K367E和Q432K突变,且M2氨基酸位点发生S31N突变.2株广西猪源H9N2亚型流感病毒HA蛋白连接HA1和HA2的氨基酸均为RSSR↓GLF;HA蛋白存在1个因P315S突变而新增的潜在糖基化位点(NCS);NA蛋白未缺失NA潜在糖基化位点,也未出现NA蛋白颈部杆状结构63~65 aa缺失现象,在NA潜在糖基化位点中69、86、146、200和234 aa处非常保守,但发生W402S突变.[结论]从广西百色分离获得的2株猪源H9N2亚型流感病毒(SW/GX/P2/2011株和SW/GX/P3/2011株)虽为低致病力毒株,但在流感病毒基因重组过程中发挥重要作用,且其致病性有增强趋势,已对金刚烷胺类药物产生耐药性.因此,应加强广西地区哺乳动物H9N2亚型流感病毒的监控,并警惕其跨种间传播. 相似文献
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Fernald RD 《Science (New York, N.Y.)》2006,313(5795):1914-1918
Light has been exploited for information by organisms through the evolution of photoreceptors and, ultimately, eyes in animals. Only a handful of eye types exist because the physics of light constrains photodetection. In the past few years, genetic tools have revealed several parallel pathways through which light guides behavior and have provided insights into the convergent evolution of eyes. The gene encoding opsin (the primary phototransduction protein) and some developmental genes had very early origins and were recruited repeatedly during eye evolution. Eye lens proteins arose separately and make up a diverse group, many of which were co-opted from other functions. A major challenge now is understanding how newly discovered pathways for processing light evolved and how they collaborate with eyes to harvest information from light. 相似文献