| 摘要: |
| 为检测10 个半滑舌鳎(Cynoglossus semilaevis)家系MHCⅡB(Cyse-DAB)基因的多态性水平、MHCⅡ类B 位点数目以及平衡选择的作用, 作者利用多聚酶链式反应(PCR)和直接测序的方法对10 个半滑舌鳎家系MHCⅡB 基因位点遗传变异和平衡选择进行了研究。用特异性引物和PCR 扩增的半滑舌鳎MHCⅡB 基因片段大约397 bp, 包含一部分第一外显子, 全部第一内含子和全部第二外显子。10个半滑舌鳎家系中, 每家系选取5 个体, 每个体5 个克隆序列分析发现60 个不同序列, 代表60 个等位基因, 其中有28 个是新发现的, 已提交到GenBank。同源分析表明60 个等位基因相似性为89.36%。共50 个个体中, 有6 个存在5 个不同等位基因, 表明在半滑舌鳎至少存在3 个座位。有9 个家系的MHCⅡB 序列多肽结合区(PBR)的非同义替换(dN)显著高于同义替换(dS)。 |
| 关键词: 半滑舌鳎(Cynoglossus semilaevis) 多态性 MHCⅡB 平衡选择 |
| DOI：10.11759//hykx20140803002 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目 (31360638); 云南省教育厅科学研究基金重大专项项目(ZD2013009); 云南省中青年学术和技术带头人后备人才资助项目(2015HB059); 红河学院中青年学术带头人后备人才资助项目(2014HB0203); 红河学院硕博资助项目(14bs11) |
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| Polymorphisms and balancing selection in the half-smooth tongue sole, Cynoglossus semilaevis |
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| Abstract: |
| In order to detect the polymorphism, number of alleles, and equilibrium selection of the MHC II B (Cyse-DAB) gene ofthe half smooth tongue sole, Cynoglossus semilaevis, we measured the genetic variation and balancing selection at MHC IIB loci in 10 half-smooth tongue sole by polymorphism chain reaction and the direct sequence method. We cloned and sequenced a 397bp fragment of the MHC class IIB exon2. An amplified fragment spanned the partial exon1, complete intron1, and exon2. Five clones and five fry per individual (n = 50, 10 groups) were selected for MHC IIB sequence analysis. A total of 60 sequences were discovered which revealed 60 alleles, 28 of which were first found in this study and have been submitted to Genbank. The homology similarity was 89.36% among the sixty sequences. Five distinct sequences were presented in each of six individuals which denoted that there were at least three loci in half-smooth tongue sole MHC class IIB genes. Non-synonymous (dN) substitution was significantly higher than synonymous (dS) in the peptide-binding region of the MHC IIB gene in nine of the ten half-smooth tongue sole groups. |
| Key words: half-smooth tongue sole Cynoglossus semilaevis polymorphism MHC IIB balancing selection |
