【作者】 王飞；

【导师】 赵志辉；

【作者基本信息】 吉林大学 ， 动物遗传育种与繁殖， 2007， 硕士

【摘要】 线粒体DNA D-Loop环区是动物线粒体的调控区和唯一的非编码区,它是线粒体基因组中序列和长度变异最大的区域。D-loop的碱基替换率比mtDNA分子的其他区域高5～10倍,是核单拷贝基因的25～100倍。细胞色素B(Cyt B)是线粒体呼吸链上电子传递的细胞色素之一,它包含8个跨膜区的螺旋,通过膜内或膜间区域相连结,哺乳动物线粒体细胞色素B(Cyt B)是构成线粒体氧化磷酸化系统复合体Ⅲ的蛋白质之一,也是其中唯一由线粒体基因组编码的蛋白质。本试验以延边黄牛、鲁西黄牛、草原红牛和日本黑牛为研究对象,根据牛线粒体DNA非编码区D-loop环全长序列和细胞色素B (Cyt B)基因部分编码区序列,结合生物信息学方法,检测了北方地区地方品种牛的线粒体D-Loop和细胞色素B基因的部分序列的多态性。通过DNAsp、MEGA3.1等分子进化软件分析发现,在11头日本黑牛群体中,存在9种D-loop单倍型,3种Cyt B单倍型,8头鲁西黄牛发现7种D-loop单倍型,2种Cyt B单倍型,11头草原红牛发现11种D-loop单倍型,5种Cyt B单倍型,10头延边黄牛9种D-loop单倍型,3种Cyt B单倍型。Kimura双参数遗传距离分析和构建分子进化树结果表明日本黑牛与延边黄牛、草原红牛存在较近的亲缘关系,而与鲁西黄牛亲缘关系较远,这与鲁西牛是由北方蒙古利亚牛系和南方瘤牛的混血种,鲁西牛与东南亚牛种亲缘关系较近的研究结论基本一致。日本黑牛489号个体与鲁西黄牛中D-loop单倍型H18、H19、H21有较近的亲缘关系。更多还原

【Abstract】 Mitochondron is unique extranuclear heredity factor in mammal and also the center of energy metabolism, which can biosynthesis fatty acid and some protein.Mitochondrial D-loop region is the unique noncoding region, which have maximal variation in mitochondrial genome, including sequence composition and length. Cytochrome B (CytB) is in charge of transferring electron on mitochondrial respiratory chain. It is also the unique coding protein in mitochondrial genome. In field of phylogenic evolution research, it is always an available molecular labeling. More and more mammalian phylogenesis was analyzed with CytB gene polymorphism recently.Mitochondrial DNA polymorphisms contributed to nucleotide and number variation that existed in mitochondrial DNA hypervariable region. There are five types of mutation, including transition, transversion, insertion, deletion and the coexistance of transition and transvertion.The kimura 2-parameter distances and base substitution, composition, variation were analyzed with MEGA software, the percentage differences among them were calculated with DNAstar software, and the polymorphic sites were analyzed with DNAsp software. The phylogenic trees constructed by three methods (UPGMA-tree,NJ-tree,ME-tree) which supported almost the same topology. The topology structures of different phylogenic trees were similar and discrepancies are not significant. It indicated that phylogenic trees wereaccurate.The polymorphism of D-loop complete sequence and CytB gene partial sequence with northern cattle strains including Luxi yellow, YanBian yellow, CaoYuan red and alien Japan black cattle were studied in this research. The relationship of four populations was analyzed with bioinformation methods.The results of mtDNA D-loop(CytB) polymorphism analysis showed that there were 7(2) haplotypes in 8 Luxi Yellow, the average haplotype diversity was 0.964±0.006 (0.536±0.123); 9(3) haplotypes in 11 Japan Black, the average haplotype diversity was 0.964±0.003(0.473±0.162); 9(3) haplotypes in 10 YanBian yellow, the average haplotype diversity was 0.978±0.003 (0.182±0.144); 11(5) haplotypes in 11 CaoYuan red, the average haplotype diversity was 1.000±0.005(0.644±0.152).D-loop Kimura 2-parameter distance between breeds were 0.0162, 0.0190, 0.0196, 0.0308, 0.0333, and 0.0354 respectively. By pairwise comparison, the closest distance was 0.0162 between Japan Black and YanBian yellow; the farest distance was 0.0354 between Luxi yellow and YanBian yellow. The phylogenic analysis revealed that the Luxi yellow cattle is the farest relation to the other breeds, the Japan black is more closely related to the YanBian yellow than to that of the other breeds.Cyt B Kimura 2-parameter distance between breeds is 0.0025, 0.0035, 0.0040, 0.0063, 0.0077, and 0.0078 respectively. By pairwise comparison,the Luxi yellow is also the most farthest relation to the other breeds. Japan black cattle 489,463 is special compared with the other cattle intraspecies. It suggests that maybe they are hybrid individuals.更多还原