四种犬科(Canidae)动物线粒体DNA分子进化  

THE MITOCHONDRIAL DNA EVOLUTION OF FOUR SPECIES OF CANIDAE

作　　者：兰宏[1] 施立明[1] 

机构地区：[1]中国科学院昆明动物研究所细胞与分子进化开放研究实验室,昆明650223

出　　处：《动物学报》1996年第1期87-95,共9页ACTA ZOOLOGICA SINICA

摘　　要：以９种限制性内切酶分析家犬、狼、赤狐、貉共７只动物的线粒体ＤＮＡ限制性片段长度多态性（ｍｔＤＮＡ ＲＦＬＰ），通过双酶解法构建各种动物的限制性内切酶图谱，用 ＵＰＧ法、 ＮＪ法和简略法分析这些动物之间的遗传关系．结果表明：１．犬的个体差异小，而赤狐的个体间遗传分化程度非常高，２．犬和狼的亲缘关系很近，应是同一种动物；３．在属间关系中，犬属与狐属的关系较接近，貉属是一个较早分化的独立分支．Animal mitochondrial DNA (mtDNA) is a circular molecule of about 16, 500 base pairs. Because mtDNA is maternally inherited and its rate of nucleotide substitution is more rapid than that of the nuclear DNA, mtDNA polymorphism, as revealed by restriction endonuclease analysis and nucleotide sequence data of polymorphic sites, have become a useful tool in investigating variations within a species. The mtDNA RFLP analysis uses two kinds of data: fragment comparison or site comparison. Phylogenetic relationship from site data is more reliable, even though mapping the sites is a little tedious. Nowadays, only those papers that obtain data from site comparison are acceptable internationally. For a long time, there have been 2 major strategies commonly used for clustering, the un-weighted pair-group (UPG) clustering method and the neighbor joining (NJ) method. The former is more understandable while the latter more accurate in details. A combination of these 2 methods is recommended for constructing the molecular dendrogram from the genetic distance matrix. However, at present, scientists have recognized that information from the discrete characters is more reliable. The characters are independent from each other. Each of them is treated separately in certain computational algorithm, out of which the parsimony method and the maximum likelihood are the most effective ones. By using these methods, the phylogenetic tree that reflects the evolutionary relationship among taxa can be constructed. This approach is called 'Numeral Cladistics'. The family Canidae of the order Carnivora, includes four genus in China: Cants, Vulpes, Nyctereutes and Cuon. Early study of taxonomy described the classification of canids, but some phylogenetic questions still left unsolved. Recent reports on mitochondrial DNA restriction fragment length polymorphism (RFLP) showed that Cuon mesomelas was very rich in intraspecific genetic diversity, and that interspecific hybridization was popular between Cants lupus and C. latrans. However, we h

关 键 词：食肉目 犬科 线粒体DNA 分子进化 

分 类 号：Q959.838[生物学—动物学]