Trifonov Vladimir A, Stanyon Roscoe, Nesterenko Anastasia I, Fu Beiyuan, Perelman Polina L, O'Brien Patricia C M, Stone Gary, Rubtsova Nadezhda V, Houck Marlys L, Robinson Terence J, Ferguson-Smith Malcolm A, Dobigny Gauthier, Graphodatsky Alexander S, Yang Fengtang
Institute of Cytology and Genetics, Russian Academy of Sciences, Novosibirsk, 630090, Russia.
Chromosome Res. 2008;16(1):89-107. doi: 10.1007/s10577-007-1201-7.
The order Perissodactyla, the group of odd-toed ungulates, includes three extant families: Equidae, Tapiridae, and Rhinocerotidae. The extremely rapid karyotypic diversification in perissodactyls has so far prevented the establishment of genome-wide homology maps between these three families by traditional cytogenetic approaches. Here we report the first genome-wide comparative chromosome maps of African rhinoceroses, four tapir species, four equine species, and humans. These maps were established by multidirectional chromosome painting, with paint probes derived from flow-sorted chromosomes of Equus grevyi, Tapirus indicus, and Ceratotherium simum as well as painting probes from horse and human. The Malayan tapir (Tapirus indicus), Baird's tapir (T. bairdii), mountain tapir (T. pinchaque), lowland tapir (T. terrestris), and onager (E. hemionus onager), were studied by cross-species chromosome painting for the first time. Our results, when integrated with previously published comparative chromosome maps of the other perissodactyl species, have enabled the reconstruction of perissodactyl, ceratomorph, and equid ancestral karyotypes, and the identification of the defining evolutionary chromosomal rearrangements along each lineage. Our results allow a more reliable estimate of the mode and tempo of evolutionary chromosomal rearrangements, revealing a striking switch between the slowly evolving ceratomorphs and extremely rapidly evolving equids.
奇蹄目，即奇蹄有蹄类动物群体，包括三个现存科：马科、貘科和犀科。迄今为止，奇蹄目动物中极其快速的核型多样化使得通过传统细胞遗传学方法在这三个科之间建立全基因组同源图谱变得困难。在此，我们报告了非洲犀牛、四种貘、四种马科动物和人类的首张全基因组比较染色体图谱。这些图谱是通过多向染色体涂染建立的，涂染探针来自细纹斑马、印度貘和白犀的流式分选染色体，以及马和人类的涂染探针。马来貘（印度貘）、拜氏貘、山地貘、低地貘和中亚野驴首次通过跨物种染色体涂染进行了研究。我们的研究结果与之前发表的其他奇蹄目物种的比较染色体图谱相结合，使得重建奇蹄目、犀超科和马科的祖先核型成为可能，并确定了每个谱系中决定性的进化染色体重排。我们的研究结果使得对进化染色体重排的模式和速度进行更可靠的估计成为可能，揭示了进化缓慢的犀超科动物和进化极其快速的马科动物之间的显著转变。
