东海带鱼不同群体遗传多样性研究

发布时间：2017-12-28 12:02

本文关键词：东海带鱼不同群体遗传多样性研究　出处：《浙江海洋大学》2017年硕士论文　论文类型：学位论文

【摘要】：带鱼(Trichiurus lepturus)隶属鲈形目(Perciformes),带鱼科(Trichiuridae),带鱼属(Trichiurus),是东海区最重要的经济鱼类,捕捞产量常年居于各种经济鱼类首位。本研究通过PCR技术扩增东海带鱼三个群体(群体A(122°32′E 29°55′N)、群体B(123°30′E 26°75′N)、群体C(124°24′E 27°26′N))线粒体COI和16S rRNA基因序列,对三个群体东海带鱼遗传多样性进行分析。在此基础上,利用直接测序法对舟山渔场-ZS(122°32′E 29°55′N)、温台渔场-WT(124°24′E 27°26′N)、鱼外渔场-YW(125°47′E 29°44′N)、闽东渔场-MD(122°54′E 26°41′N)带鱼群体的线粒体控制区及COI基因区域进行SNP位点挖掘与位点多态性进行研究。主要研究结果如下:1.对东海三个群体72尾带鱼线粒体COI和16S rRNA基因扩增,得到1130 bp的COI基因序列片段和554 bp的16S rRNA序列片段,其中COI基因片段的T、C、A、G和A+T含量分别为29.0%、28.9%、24.4%、17.7%和53.4%;16S rRNA基因片段的T、C、A、G和A+T含量分别为22.7%、27.6%、28.0%、21.7%和50.7%,A+T含量均略高于C+G,与其他硬骨鱼类线粒体DNA COI和16S rRNA基因片段的碱基组成特征相符。COI基因片段检测出43个单倍型、49个多态位点、转换/颠换率为6;16S rRNA基因片段检测出8个单倍型、8个多态位点、转换/颠换率为7,两种基因序列变异均未达到饱和状态,COI基因片段比16S rRNA基因片段变异丰富。使用邻接法构建的分子进化树揭示同一群体内大部分个体首先聚在一起,存在不同群体间带鱼个体聚合。分析结果表明,群体A遗传背景较群体B、群体C丰富,群体内部个体差异大于群体间差异,群体间基因交流频率较高,遗传分化不明显,基于线粒体COI和16S rRNA基因序列东海带鱼三个群体的遗传多样性偏低。2.通过带鱼线粒体控制区以及COI基因序列的比对筛选,获得10个候选SNP位点,设计10组引物扩增相应的基因区域,结果发现,观测杂合度(Ho)分布范围为0.0625~0.2812,期望杂合度(He)分布区间在0.1190~0.3989,Tl-10位点极显著偏离哈代-温伯格平衡(P0.01),其他9个SNP位点均符合连锁平衡,处于平衡状态(P0.05)。Tl-08、Tl-09位点的多态信息含量(PIC)分别为0.2713、0.3140,属于中度多态水平(PIC0.5),Tl-01、Tl-02、Tl-03、Tl-04、Tl-05、Tl-06、Tl-07位点的多态信息含量(PIC)处于0.1103~0.2125之间。
[Abstract]:Hairtail (Trichiurus lepturus) belong to Perciformes (Perciformes), Trichiuridae (Trichiuridae), Trichiurus (Trichiurus), is the most important economic fishes in the East China Sea, fishing production in all kinds of economic fish in the first year. In this study, we amplified three mitochondrial populations (group A (122 degree 32 'E 29 degree 55' N), group B (123 degree 30 'E 26 degree 75' N), and C C (124 124 24 'E N degree N' N) by PCR technology. On this basis, the Zhoushan fishing ground using -ZS direct sequencing (122 degrees 29 degrees 32 'E 55' N), Wenzhou fisheries -WT (124 degrees 27 degrees 24 'E 26' N), fish fishing -YW (125 degrees 29 degrees 47 'E 44' N, -MD (122) Mindong Fishing Ground 26 degrees 41 degrees 54 'E' N) mitochondrial control region and COI gene region of SNP loci of Trichiurus haumela mining research and polymorphism. The main results are as follows: 1. in the East China Sea three groups 72 tail hairtail mitochondrial COI and rRNA gene was amplified by 16S, 16S rRNA fragment of COI gene fragment of 1130 BP and 554 BP, the COI gene fragment, C, A, T, G and A+T contents were 29%, 28.9%, 24.4%, and 17.7% 53.4%; 16S rRNA gene fragment T, C, A, G and A+T were respectively 22.7%, 27.6%, 28%, 21.7% and 50.7%, the content of A+T was slightly higher than the C+G, features consistent with other teleost mitochondrial DNA COI and 16S rRNA gene fragments in base composition. The COI gene fragment detected 43 haplotypes, 49 polymorphic loci, the transition / transversion rate was 6; 16S rRNA gene fragment detected 8 haplotypes, 8 polymorphic loci, the transition / transversion rate was 7, two gene sequences were not saturated, COI gene fragment 16S rRNA gene fragment abundant variation. The molecular evolution tree constructed by the adjacency method reveals that most of the individuals in the same group are first gathered together, and there are different groups of fish individual aggregation. The analysis results show that the genetic background of A group in group B, group C is rich, individual differences within groups is greater than the difference between groups, the higher frequency of gene flow between populations, the genetic differentiation was not obvious, mitochondrial COI and 16S rRNA gene sequence of hairtail in three populations of low genetic diversity based on. The screening of 2. control region and COI gene sequence by hairtail mitochondrial alignment, obtained 10 candidate SNP loci, 10 groups of primers to amplify the gene region, the corresponding results, the observed heterozygosity (Ho) was in the range of 0.0625~0.2812, the expected heterozygosity (He) distribution in the range of 0.1190~0.3989, Tl-10 loci significantly deviated from Hardy - Weinberg the balance (P0.01), the other 9 SNP sites were consistent with linkage equilibrium in equilibrium (P0.05). The polymorphic information content (PIC) of Tl-08 and Tl-09 loci was 0.2713 and 0.3140, respectively, belonging to the moderate polymorphism level (PIC0.5), and the polymorphic information content (Tl-01) of Tl-01, Tl-02, Tl-03, Tl-04, Tl-05, Tl-06 and Tl-07 were between.
【学位授予单位】：浙江海洋大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S917.4

【相似文献】