金丝猴毛首线虫线粒体cox1基因序列分析

为阐明金丝猴毛首线虫线粒体细胞色素c氧化酶Ⅰ亚基(cox1)基因部分(pcox1)序列的遗传变异情况,以长沙生态动物园金丝猴体内分离的毛首线虫作为研究对象,根据cox1序列构建其与其他毛首线虫的进化发育关系。使用PCR方法扩增金丝猴毛首线虫线粒体cox1,然后将所测得的序列应用Clustal X 1.81程序进行比对,最后用Mega 5.0程序NJ法绘制种系发育树。结果显示,本实验扩增获得的6条毛首线虫分离株cox1序列长度一致,均为411 bp,种内变异为0。种系发育分析结果表明,这6条毛首线虫分离株位于同一分支。鉴于金丝猴毛首线虫的cox1基因种内保守,而种间差异大(24.0%~34.1%),因此可以作为种间鉴定检测研究的遗传标记。本研究结果为进一步研究金丝猴毛首线虫的群体遗传结构奠定了基础。

基于cox1基因对中国青藏高原地区细粒棘球绦虫遗传多态性的研究

通过对中国青藏高原地区细粒棘球绦虫的遗传多态性分析,了解该地区细粒棘球绦虫的遗传变异情况,为细粒棘球蚴病的防治提供基础材料。基于线粒体cox1基因全序列(1 609bp)分析中国青藏高原地区47个细粒棘球绦虫分离株的序列变异情况,并结合NCBI数据库中已公布的中国青藏高原和中东地区所有细粒棘球绦虫cox1基因全长序列,对比分析两个种群的遗传多态性特征。结果显示,47个样品均被确定为G1基因型,分为10个单倍型(C1~C10),其中优势单倍型C1与中东优势单倍型相同,且该单倍型呈世界性分布。中国青藏高原地区细粒棘球绦虫的单倍型多样性(Hd)与核苷酸多样性(π)较低,明显低于中东种群,两个地区Tajima’s D和Fu’s Fs检验值均为负值,遗传结构差异不显著。研究结果表明:中国青藏高原细粒棘球绦虫可能是由一个起源于中东的有效种群进入该地区后,经历了近期群体扩张或遗传瓶颈,在高原地区天然的地理隔离作用下,逐渐发展成了现在的种群。

用cox1基因片段的PCR鉴别亚洲带绦虫和牛带绦虫

目的:用cox1基因片段的PCR技术对亚洲带绦虫和牛带绦虫的快速鉴别。方法:用亚洲带绦虫和牛带绦虫线粒体cox1基因片段的特异性引物以及带绦虫cox1基因片段的通用引物,对贵州省都匀地区和从江地区的带绦虫虫卵和节片DNA进行常规PCR扩增,扩增产物经琼脂糖凝胶电泳检测和核酸序列测定,并用NC-BI Blast对扩增产物的核酸序列与NCBI数据库中带绦虫的cox1基因进行比对。结果:5株都匀带绦虫DNA样品经亚洲带绦虫cox1基因片段的特异性引物PCR,均扩增出约260 bp的产物,PCR产物的核酸序列与NCBI数据库中亚洲带绦虫线粒体cox1基因片段的同源性为100%;2株从江带绦虫的DNA样品用亚洲带绦虫特异性引物和牛带绦虫特异性引物的PCR均未见扩增产物,而通用引物PCR则扩增出约1 000 bp的产物,核酸序列与NCBI数据库中牛带绦虫线粒体cox1基因片段的同源性为99%,在牛带绦虫特异性引物的结合位点存在一个碱基差异。结论:常规PCR扩增特异性的cox1基因片段可快速鉴定亚洲带绦虫;从江牛带绦虫株的cox1基因特异性片段部分存在变异,导致与特异性引物结合能力的差异,可采用cox1基因通用引物PCR结合测序进行鉴定。

贵州黔南5条带绦虫的分类研究

目的用形态学方法和分子生物学方法对贵州黔南地区5条带绦虫进行分类学鉴定。方法在观察虫体头节、孕节等形态的基础上,采用带绦虫线粒体细胞色素C氧化酶亚单位1(cy-tochrome c oxidase subunit 1,cox1)基因片段的特异性引物对虫体DNA进行PCR扩增,产物经琼脂糖凝胶电泳分析。结果 5条带绦虫头节近方形,有4个吸盘,无顶突和小钩,孕节子宫每侧分支数为18～24支。以Tasia为引物的PCR扩增产物经琼脂糖凝胶电泳,均出现约260bp的条带,而以Tsag引物均未见扩增产物。结论经鉴定,所采集的4株都匀绦虫和1株独山绦虫均为亚洲带绦虫,提示贵州都匀、独山地区为亚洲带绦虫流行区。

实时荧光PCR法检测食品中梅花鹿成分

采用实时荧光聚合酶链式反应技术检测食品中梅花鹿成分。通过对梅花鹿基因序列对比分析,选取种间差异大、种内差异小的线粒体细胞色素C氧化酶亚基Ⅰ基因序列作为靶序列,利用Primer Express、Oligo和DNAMAN等软件设计了梅花鹿特异性的引物和Taq Man探针,并用已知样本对引物和Taq Man探针的物种特异性、检测灵敏度进行验证和检测。实验结果表明,引物和探针对梅花鹿成分检测的特异性良好,与其他物种DNA无非目标扩增,对梅花鹿DNA的扩增效率为91.68%,该方法的检测灵敏度达0.42 pg/反应。

Cloning,Sequencing and Molecular Phylogenetic Analysis of the Mitochondrial Cytochrome Oxidase Ⅰ Gene of Chilo suppressalis

[Objective] The research aimed at cloning and analyzing mitochondrial cytochrome oxidase I gene（cox 1）of C.suppressalis.[Method] The mitochondrial cox 1 gene of C.suppressalis was cloned with PCR method and sequenced.Then,cox1 sequences of other 21 Lepidopteran species were obtained by blasting the GenBank with cox 1 gene sequence of C.suppressalis.Finally,homology comparison and molecular phylogenitic analysis among the 22 Lepidopteran species were conducted.[Result] The open reading frame of cox 1 gene from C.suppressalis contained 1 531 nucleotides encoding a putative protein of 510 amino acids.The cox1 gene used a start codon CGA,and an incomplete termination codon composed of only T.Based on the amino acid sequences of cox 1,the molecular phylogenetic tree of Lepidoptera was reconstructed using the maximum likelihood（ML）method.The molecular phylogenetic tree was similar to the morphological phylogenetic tree mainly,but also showed some differences.[Conclusion] The result will provide reference for further research on expression and application of cox 1 gene.

Molecular Phylogeny of Pamphagidae(Acridoidea,Orthoptera) from China Based on Mitochondrial Cytochrome Oxidase I Sequences

Phylogenetic relationships of Pamphagidae were examined using cytochrome oxidase subunit I（cox1） gene sequences.Eleven species of Pamphagidae from 7 genera were sequenced to obtain mt DNA data,along with 2 species from the Gen Bank nucleotide database.The results of sequence comparisons showed the cox1 gene is 1 534 bp in length,including 326 varible sites and 211 parsimonious information sites.The percentage of A ＋T is 67.1% in the nucleotide sequences,showing a strong AT bias.Genetic distances among subfamilies are 0.08.Using Locusta migratoria as outgroup,the phylogenetic trees were reconstructed with NJ,MP,ML and Bayesian inferences,and the results showed that the clustering results were approximately identical to that of classical morphological classification.Thrinchinae and Pamphaginae were a monophyletic group,respectively.Two species of the genus Asiotmethis of Prionotropisinae did not get together with other species of Prionotropisinae,classification position of Asiotmethis should be further discussed by both genetic markers and morphological features.The current genus Filchnerella of Prionotropisinae was not a monophyletic group.

肉制品中鸵鸟源性成分的实时荧光PCR检测

通过实时荧光PCR技术检测肉制品中鸵鸟源性成分。根据鸵鸟线粒体细胞色素C氧化酶亚基Ⅰ基因(COX1)序列,用Primer Express和DNAMAN软件设计特异性的引物和Taq Man探针,并用阳性样本进行验证。结果表明,引物和探针对鸵鸟源性成分的特异性良好,与常见物种DNA无非目标扩增,该方法的检测灵敏度达0.27 pg/反应,适用于鸵鸟源性成分的鉴定,从而建立了肉制品中鸵鸟源性成分的实时荧光PCR鉴定方法 。