鸡蛔虫凉山州分离株线粒体ATP6基因的序列测定和种系发育分析

利用PCR技术,对分离自四川省凉山州17个鸡蛔虫分离株的线粒体ATP合成酶F0亚单位6基因(ATP6)的全序列进行扩增和分析。测序结果显示,所获得的鸡蛔虫ATP6全序列长度均为597bp,有25个变异位点,共检测到11个单倍型,种内变异为0.0~2.4%。种系发育树显示,所有鸡蛔虫分离株聚在同一分支,能与其他蛔虫相鉴别。结果表明,鸡蛔虫的ATP6基因序列种内变异小,种间差异大,故可作为分子标记用于鸡蛔虫的种间鉴定;鸡蛔虫凉山州分离株存在一定的遗传变异和遗传多样性。本研究结果为鸡蛔虫的分子分类、分子流行病学调查和种群遗传的进一步研究奠定了基础。     

湖南省鸡蛔虫线粒体cox1和nad1基因的序列测定及种系发育分析

本研究旨在阐明湖南省鸡蛔虫分离株线粒体细胞色素c氧化酶第I亚基(cox1)基因部分序列(pcox1)和烟酰胺腺嘌呤二核苷酸(NADH)脱氢酶亚单位l基因(nad1)部分序列(pnad1)的遗传变异情况,并用pcox1和pnad1序列构建鸡蛔虫与其它科蛔虫的种群遗传关系。作者应用聚合酶链反应(PCR)扩增鸡蛔虫虫株的pcox1和pnad1,应用ClustalX1.81程序对序列进行比对,然后用Phylip3.67程序MP法和Mega4.0程序NJ法绘制种系发育树,并用Puzzle5.2程序构建最大似然树。所获得的pcox1和pnad1序列长度均为394和408bp,种系发育树表明,20个分离株鸡蛔虫位于同一分枝。由于鸡蛔虫pcox1和pnad1序列种内相对保守,种间差异较大,故可作为种间遗传变异研究的标记。本研究系首次报道鸡蛔虫的pcox1和pnad1序列,从而为鸡蛔虫的分类鉴定以及进一步的分子流行病学调查和群体遗传研究奠定了基础。     

基于nad5基因分析白狮蛔虫种系发育关系

为分析白狮蛔虫湖南动物园分离株线粒体nad5的遗传差异,并利用nad5序列分析白狮蛔虫与其他蛔虫的种系遗传关系,应用PCR技术对白狮蛔虫线粒体nad5的部分序列进行克隆和序列测定,利用Clustal X2.0程序对测序所得序列进行比对,再运用Mega4.1程序进行NJ法绘制种系发育树。结果表明:所获得nad5序列长度基本一致,约530 bp,15个样品分离株之间的同源性为97.4%~99.8%,通过构建系统种系发育,结果显示15个白狮蛔虫分离株与狮弓蛔虫位于同一大分支,与其他蛔虫所属分支具有较远的距离,得到较为明显的鉴别。狮弓蛔虫nad5序列种内较为保守,但种间差异明显,nad5基因可以作为理想的分子标记应用于狮弓蛔虫的分子鉴定和种间遗传变异研究,从而为狮弓蛔虫的群体遗传研究奠定基础。     

鸡蛔虫线粒体cox1基因的克隆及序列分析

本研究旨在阐明鸡蛔虫分离株线粒体细胞色素c氧化酶第Ⅰ亚基(cox1)基因部分序列(pcox1)的遗传变异情况,并用pcox1序列构建其与其他蛔虫的进化关系。应用聚合酶链反应(PCR)扩增鸡蛔虫虫株的pcox1,将测定获得序列应用Clustal X 1.81程序进行比对,然后用Phylip 3.67程序MP法和Mega 4.0程序NJ法绘制种系发育树,并用Puzzle 5.2程序构建最大似然树。所获得的pcox1序列长度一致,均为250 bp,种内变异在0~2.5%之间。种系发育分析表明,8个鸡蛔虫分离株位于同一分枝。由于鸡蛔虫pcox1序列种内相对保守,种间差异较大(6.9%~15.3%),故可作为种间遗传变异研究的标记,研究结果为进一步研究鸡蛔虫的群体遗传结构奠定了基础。     

犬弓首蛔虫线粒体cox1基因的克隆及序列分析

本研究旨在阐明我国犬弓首蛔虫(Toxocara canis)湖南分离株线粒体细胞色素c氧化酶第I亚基(cox1)基因部分序列(pcox1)的遗传变异情况,并用其与其它弓首蛔虫的pcox1序列构建进化关系。应用PCR扩增犬弓首蛔虫虫株的pcox1,将所获得的序列应用Mafft 7.122程序进行比对,然后用Phy ML 3.1程序ML法绘制种系发育树。本实验扩增所获得的pcox1序列长度一致,均为394 bp,种内变异在0~2.5%之间,种间差异为8.2%~11.6%。种系发育分析结果表明,12个犬弓首蛔虫分离株位于同一分支。由于犬弓首蛔虫pcox1序列种内相对保守,种间差异较大,故可作为种间鉴定检测研究的遗传标记,本研究结果为犬弓首蛔虫的分类、鉴定和群体遗传结构奠定了基础。     

基于线粒体pcox1分析头槽绦虫种系发育关系

为阐明鱼头槽绦虫线粒体中的细胞色素c氧化酶第一亚基部分序列(pcox1)的遗传多态性,研究鱼头槽绦虫种系发育关系,以湖南省部分地区鱼头槽绦虫为研究对象,通过聚合酶链式反应(PCR)对其线粒体pcox1基因进行扩增并测序。序列分析比对后,结合Gen Bank收录的头槽绦虫以及其他科绦虫的序列,共同构建系统进化树,以此分析鱼头槽绦虫种内与种间的遗传关系。结果表明:湖南各分离株的pcox1长度为389～412 bp,各分离株间的同源性为93%～100%,与Gen Bank中收录的鱼头槽绦虫的同源性为99.2%～100%,序列均位于进化树同一分支上;本次收集的21株分离株与其他种绦虫序列的同源性为70.3%～80.0%,且进化树分支相距较远。结果说明鱼头槽绦虫的pcox1在不同地区种内均相对保守,种间差异较大,可以作为种间遗传变异研究的分子标记。     

猎豹狮弓蛔虫线粒体cox1基因的序列测定及系统发育分析

以来源于湖南省长沙生态动物园猎豹体内的狮弓蛔虫为研究对象,利用保守引物,通过聚合酶链反应(PCR),扩增猎豹狮弓蛔虫线粒体细胞色素c氧化酶I亚基基因(cox1)部分序列(pcox1),并用pcox1序列构建与其他相关蛔虫的进化关系。将获得的序列,用Clustal X 1.83程序进行比对,用Phy ML 3.0程序中的最大似然树法(ML)绘制种系进化树。结果显示:样品pcox1序列长度均为367 bp,种内相对保守(1.4%～6.8%),种间变异显著(9.7%～21.4%);种系发育关系指示,猫科动物狮弓蛔虫分离株位于同一分支,犬科动物狮弓蛔虫分离株位于另一分支。由于狮弓蛔虫cox1序列种内相对保守,种间差异较大,故可作为狮弓蛔虫种间遗传变异研究的标记。     

陕西省榆林地区鸡蛔虫核糖体18S rRNA与ITS-2序列分析及种系发育关系研究

为了探究陕西省榆林地区鸡蛔虫核糖体18S rRNA、ITS-2基因序列特征及其种系发育关系,试验以采集于该地区的28条鸡蛔虫为样品,PCR扩增其18S rRNA、ITS-2基因的部分序列,测序后分别对鸡蛔虫18S rRNA、ITS-2基因序列的碱基组成进行分析,计算A、T、G和C的含量,并对这两个基因的遗传多样性进行分析,比较其种内、种间差异,构建种系发育树。结果表明：测序所获得的鸡蛔虫18S rRNA、ITS-2基因序列的长度分别为637,350 bp;其中18S rRNA基因序列的A、T、G和C的含量分别为24.5%～25.2%、26.1%～26.4%、28.3%～28.7%和20.3%～20.9%,A+T含量为50.6%～51.6%,G+C含量为48.6%～49.6%,种内差异为0～1.6%;与猪蛔虫(MF358962)、人蛔虫(LC422643)、犬弓首蛔虫(FJ418788)及狮弓蛔虫(JF837179)种间差异为5.18%～61.38%;ITS-2基因序列中的A、T、G和C的含量分别为28.9%～29.1%、38.0%～38.6%、19.1%～19.7%与12.9%～13....     

湖南湘西地区鸡蛔虫遗传多样性及种系发育关系研究

为研究湖南省湘西地区鸡蛔虫的遗传多样性及种系发育关系,试验以采集于湖南省湘西自治州20条鸡蛔虫为研究对象,采用PCR扩增其线粒体细胞色素c氧化酶亚基Ⅲ(Cytochrome c oxidase subunit Ⅲ,cox3)和核糖体18S rRNA的部分序列。结果显示:PCR扩增获得的鸡蛔虫cox3、18S rRNA基因序列的长度分别为399 bp、637 bp,种内差异分别为0～1.5%、0～1.6%,种间差异分别为13.0%～40.1%、5.18%～61.38%;构建了基于cox3、18S rRNA基因序列的种系发育树,来自于湖南省湘西地区的鸡蛔虫均处于发育树的同一分支上。研究表明来自于湖南湘西地区的鸡蛔虫间尽管存在一定程度的基因变异和遗传多样性,但它们之间的亲缘关系较近。     

陕西省榆林地区犬弓首蛔虫的流行情况调查及其遗传多样性与种系发育关系分析

为了调查陕西省榆林地区犬弓首蛔虫的流行情况，并研究其基因变异、遗传多样性及种系发育关系，试验采用饱和盐水漂浮法对采自该地区的402份犬粪便进行虫卵检查，利用IBM SPSS Statistics 22软件对虫卵检测数据进行统计和分析，并采用χ²检验分析各地区、各类型犬感染犬弓首蛔虫的差异性；PCR扩增犬弓首蛔虫的cox1、18S rRNA基因序列并测序；运用Clustal X与DNAStar软件分析2个基因的碱基组成与遗传多样性；运用Clustal X及PhyML 3.0软件分析犬弓首蛔虫的种系发育关系。结果表明：陕西省榆林地区犬对弓首蛔虫的总感染率为20.65%,其中宠物犬的感染率为8.42%,而流浪犬的感染率为33.00%,各地区、各类型犬感染犬弓首蛔虫的情况存在一定差异；cox1基因序列长度为1 044 bp, A+T含量为61.5%～62.2%,G+C含量为37.8%～38.5%,种内差异为0～1.3%,种间差异为9.87%～14.37%;18S rRNA基因序列长度为598 bp, A+T含量为50.0%～50.5%,G+C含量为49.5%～50.0%,...     

Phylogenetic relationships in three species of canine Demodex mite based on partial sequences of mitochondrial 16S rDNA

Background – The historical classification of Demodex mites has been based on their hosts and morphological features. Genome sequencing has proved to be a very effective taxonomic tool in phylogenetic studies and has been applied in the classification of Demodex. Mitochondrial 16S rDNA has been demonstrated to be an especially useful marker to establish phylogenetic relationships. Hypothesis/Objectives – To amplify and sequence a segment of the mitochondrial 16S rDNA from Demodex canis and Demodex injai, as well as from the short‐bodied mite called, unofficially, D. cornei and to determine their genetic proximity. Methods – Demodex mites were examined microscopically and classified as Demodex folliculorum (one sample), D. canis (four samples), D. injai (two samples) or the short‐bodied species D. cornei (three samples). DNA was extracted, and a 338 bp fragment of the 16S rDNA was amplified and sequenced. Results – The sequences of the four D. canis mites were identical and shared 99.6 and 97.3% identity with two D. canis sequences available at GenBank. The sequences of the D. cornei isolates were identical and showed 97.8, 98.2 and 99.6% identity with the D. canis isolates. The sequences of the two D. injai isolates were also identical and showed 76.6% identity with the D. canis sequence. Conclusion – Demodex canis and D. injai are two different species, with a genetic distance of 23.3%. It would seem that the short‐bodied Demodex mite D. cornei is a morphological variant of D. canis.     

吸虫线粒体基因组及其应用研究进展

吸虫病(Trematodiasis)如血吸虫病、肝片形吸虫病等是一类重要的人兽共患寄生虫病,在我国和世界各地普遍流行,危害严重。本文将对吸虫线粒体基因组全序列分析的研究进展、应用和今后的发展方向作一综述。目前,已完成包括复殖亚纲10个种和单殖亚纲4个种总计14种吸虫线粒体基因组全序列测定。吸虫线粒体基因组碱基组成、基因结构与排列、基因变异等分析结果为线粒体功能基因组学研究、比较基因组学研究、分子分类学研究、物种起源、分子系统发育与进化分析及其疾病诊断等提供了重要依据和指导作用。线粒体基因组序列分析有助于解决一些新近发现的种如三平并殖吸虫、中华血吸虫等独立种的分类地位;而怡乐村并殖吸虫和佐渡并殖吸虫是大平并殖吸虫的同物异名吸虫。日本片形吸虫与大片形吸虫的cox1基因序列完全一致,这些日本片形吸虫应为大片形吸虫;大片形吸虫不同株虽然在cox1基因序列上无差异,但nad1基因却有8.3%变异性,这表明大片形吸虫不同株中可能存在隐蔽种。总之,线粒体基因组序列可为吸虫虫种与虫株的分类学地位的确定提供重要依据。同时,人们可根据线粒体基因组序列,通过PCR方法有效地对临床上易混淆的吸虫的种、株或群等作出确切的鉴别与诊断,从...     

Phylogenetic analysis of Fusobacterium necrophorum, Fusobacterium varium and Fusobacterium nucleatum based on gyrB gene sequences

The nucleotide sequences of the DNA gyrase B subunit gene (gyrB) of Fusobacterium necrophorum subsp. necrophorum, F. necrophorum subsp. funduliforme and F. varium were determined and analyzed together with those of F. nucleatum subsp. nucleatum and F. nucleatum subsp. vincentii. On the phylogenetic tree constructed, the strains of each fusobacterial species formed distinct clusters with deep sublines. The degree of sequence similarity within each cluster was 93.2% or more, whereas similarities between clusters ranged from 70.1 to 72.7%. These clusters were recovered with 100% bootstrap probabilities and are in very good agreement with the species of Fusobacterium. These data suggest that gyrB is an accurate genealogical marker for the classification of the fusobacterial taxa considered in this study.     

Phylogenetic analysis of Portuguese Feline Immunodeficiency Virus sequences reveals high genetic diversity

Feline Immunodeficiency Virus (FIV) is a Lentivirus responsible for an immunodeficiency like disease in domestic cats. Based on the genetic diversity of the V3-V5 region of env gene FIV is divided in five phylogenetic subtypes (A, B, C, D and E) with a world-wide distribution. To understand the subtype diversity of FIV in Portugal a serological survey was conducted during 1 year in the Veterinary Faculty Hospital, Lisbon, Portugal to identify seropositive animals. Two viral genomic regions were amplified by a nested PCR, sequenced and the phylogenetic relationships between 24 new Portuguese FIV sequences and other previously published FIV isolates were assessed. The introduction of these sequences induced a subclustering in subtype B including most of the new Portuguese sequences. Moreover, a new cluster emerged, with two highly divergent new sequences that might represent a new subtype. The study of these new FIV isolates showed the presence in Portugal of a unique viral population subclustering within subtype B and of sequences clearly divergent from the five known subtypes, providing a contribution for the understanding of FIV's genetic diversity.     

Phylogenetic analysis of the erythrocytic Anaplasma species based on 16S rDNA and GroEL (HSP60) sequences of A. marginale,A. centrale,and A. ovis and the specific detection of A. centrale vaccine strain

Phenotypic criteria for the identification of erythrocytic ruminant Anaplasma species has relied on subjective identification methods such as host pathogenicity (virulence for cattle or sheep) and/or the location of Anaplasma inclusion bodies within the host's red cells. Sequence comparisons of new and available GenBank Accessions were investigated to elucidate the relationships among these closely related Anaplasma species. Twenty-one 16S rDNA and GroEL (HSP60) sequences from 13 Anaplasma marginale (South Africa, Namibia, Zimbabwe, Israel, USA, Australia and Uruguay), three A. centrale (South Africa and Japan), two A. ovis (USA and South Africa), and two unknown Anaplasma species isolated from wild ruminants (South Africa), were compared. 16S rDNA maximum-likelihood and distance trees separated all A. marginale (and the two wild ruminant isolates) from the two South African A. centrale (including original vaccine strain, Theiler, 1911). The Japanese A. centrale (Aomori) demonstrated the lowest sequence identity to the remaining erythrocytic Anaplasma species. A. ovis inter-species relationships could not be resolved through the 16S rDNA analyses, whereas strong bootstrap branch support is demonstrated in the GroEL distance tree using A. ovis OVI strain. All erythrocytic Anaplasma species and isolates were confirmed to belong to the same cluster showing strong branch support to Anaplasma (Ehrlichia) phagocytophilum with Ehrlichia (Cowdria) ruminantium and Rickettsia rickettsii serving as appropriate out-groups. Based on groEL sequences, a specific PCR method was developed which amplified A. centrale vaccine (Theiler, 1911) specifically. This study confirms the suitability of 16S rDNA sequences to define genera and demonstrates the usefulness of GroEL sequences for defining species of erythrocytic Anaplasma.     

贵州黎平黄牛线粒体DNA D-loop区全序列初步分析

为了解贵州黎平黄牛的遗传多样性及遗传背景,我们测定了20头黄牛的线粒体DNA D-loop区序列。结果检测到8种单倍型,其中4种为普通牛血统的单倍型,4种为瘤牛血统的单倍型,表明黎平黄牛同时受普通牛和瘤牛的影响。该研究对于黎平黄牛的保种及持续利用有着重要的理论指导意义。     

基于线粒体nad4基因探讨土耳其斯坦东毕吸虫的系统发生位置

为探讨土耳其斯坦东毕吸虫在血吸虫中的系统发生位置,本研究设计一对特异性引物,通过PCR方法对土耳其斯坦东毕吸虫(绵羊源)线粒体烟酰胺脱氢酶亚基Ⅳ基因(nad4)进行扩增和测序分析,并与GenBank中相关血吸虫nad4基因进行比对。结果显示,本研究克隆的该吸虫线粒体nad4基因序列大小约为1030bp,与已发表的其它血吸虫线粒体nad4基因的同源性为51.6%～66.7%,其系统发生位置属于非洲血吸虫种群。     

Phylogenetic relationships of rodent pinworms (genus Syphacia) in Japan inferred from mitochondrial CO1 gene sequences

Species of the genus Syphacia are considered to have generally co-evolved with their rodent hosts. This study determined partial sequences of the CO1 gene from several species in the genus Syphacia and discuss the relationships between pinworms and their hosts. Syphacia montana, which parasitizes Microtinae, was closely related to S. frederici and S. obvelata, which parasitize Murinae. Although both S. obvelata and S. ohtaorum parasitize rodents in the genus Mus, these two species were not found to be closely related to each other. Syphacia frederici, S. emileromani and S. agraria are all pinworms of the Apodemus species, but genetic affiliation between these three species was not indicated. These facts suggest that the co-evolutionary relationship between species of the genus Syphacia and their host rodents may not so strict and host switching has probably occurred during the course of evolution.     

山东地区2株基因Ⅶ型新城疫病毒的全基因组测序及其序列分析

测定了基因Ⅶ型新城疫(Newcastle disease,ND)强毒分离株Chicken/China/SD04/2011和Chicken/China/SDWF07/2011的全基因序列,将其与GenBank中已发表的29株基因Ⅶ型新城疫毒株的全基因序列进行比对,同源性在91％～97％之间.2株基因Ⅶ型分离株与中国标准强毒F48E8、国外标准强毒Herts/33及疫苗株chicken/N.Ireland/Ulster/67、B1、Clone30、LaSota、Mukteswar核苷酸序列同源性在83％～87％之间;其F蛋白前体F0裂解位点附近的氨基酸序列均为112RRQKRF117,符合NDV强毒株的特征;与单抗1E5反应阴性,结合对各蛋白的抗原位点的分析初步推测2株病毒的抗原性可能发生了变化.