【摘要】 2008年5月至2009年5月间对渤海鱼类寄生线虫的幼虫进行了采集。通过形态学观察,从172条(5种)鱼类体内共鉴定出612条异尖属线虫的幼虫。每条幼虫分布提出基因组DNA,利用PCR技术扩增出ITS区,并用限制性内切酶(HinfⅠ,TaqⅠand HhaⅠ)进行酶切分析。随后选择有代表性的样品进行ITS-1,ITS-2,以及线粒体DNA SSU序列分析。对612个样品进行酶切分析后,发现两种不同的基因型,其中603个样品为派氏异尖线虫Anisakis pegreffii,9个样品为重组基因型。因此渤海鱼类中派氏异尖线虫为优势种,占所检测样品的98.5%。对重组基因型的ITS-1和IT S-2进行序列分析表明有两种不同的重组基因型,重组基因型Ⅰ(RecⅠ)与以前报道的杂交种相同,在ITS-1的280和296部位有C/T的杂合;而重组基因型Ⅱ代表一种新的重组基因型,它只在296部位有C/T的杂合。线粒体DNA SSU序列分析表明两种重组基因型的序列与派氏异尖线虫完全相同。该结果表明重组基因型有可能是一种祖先多态性的保留。更多还原

【Abstract】 A total of 612 larval specimens of Anisakis from 172 fishes( representing 5 species) from the Bohai Sea,China from May 2008 to May 2009 was identified based on morphological characters. From the genomic DNA of all individual specimens,a region of nuclear ribosomal DNA was amplified by polymerase chain reaction( PCR),follow ed by restriction endonuclease digestion with endonucleases( Hinf Ⅰ,T aq Ⅰ and H ha Ⅰ). Subsequently,IT S-1 and IT S-2,and mtDNA SSU gene of the selected samples w ere sequenced. The RFLP patterns of the 612 samples indicated two different genotypes representing Anisakis pegreffii( n = 603) and recombinant genotype( n = 9). Thus,Anisakis pegreffii was the dominant species,accounting for 98. 5 % of the total number of specimens examined herein. The sequence analysis of IT S-1 and IT S-2 in the recombinant genotype revealed two different genotypes,the recombinant subtype Ⅰ( Rec Ⅰ) representing"hybrid"with heterozygotes C /T at positions 280 and 296 of the aligned sequences reported previously,whereas recombinant subtype Ⅱ( Rec Ⅱ) representing an un-described recombinant with heterozygote C / T at position 296 of the aligned sequences. MtDNA SSU sequencing indicated the sequences of Rec Ⅰ and Rec Ⅱ have same parental origin from Anisakis pegreffii. The result supported that the recombinant subtypes might be the retention of ancestral polymorphism.更多还原