比较染色体涂色显示小熊猫(Ailurus fulgens)具有高度保守的核型  

Comparative Chromosome Painting Shows the Red Panda (Ailurus fulgens) Has A Highly Conserved Karyotype

作　　者：田颖[1] 佴文惠[1] 王金焕[1] 杨云飞[1] 杨凤堂[1] 

机构地区：[1]中国科学院昆明动物研究所,昆明650223

出　　处：《Acta Genetica Sinica》2002年第2期124-127,T001,共5页

基　　金：国家杰出青年基金 (3 0 0 2 5 0 2 6)资助项目的部分研究内容~~

摘　　要：以狗的整条染色体特异探针 ,通过比较染色体涂色 (ComparativeChromosomePainting) ,建立了小熊猫和狗的比较染色体图谱。狗的 38条常染色体探针在小熊猫染色体上共检出 71个同源片段。其中狗的 18条常染色体每一条在小熊猫染色体上各有 1个同源片段 ,其余的 2 0条常染色体每一条在小熊猫染色体上各有 2至 5个同源片段。广泛的染色体结构重排造成了小熊猫与狗的核型差异 :至少需要经过 2 8次断裂 ,4 9次融合 ,4次倒位才能将狗的核型 (2n =78)“转变”为小熊猫的核型 (2n =36 )。结合已发表的狗与家猫的比较染色体图谱 ,我们推测 :小熊猫与家猫之间共存在 2 6个同源片段 ,二者的核型之间显示了较高的同源性。通过比较分析狗的染色体同源片段在小熊猫与家猫染色体上的分布和排列 ,可以看出 :4次染色体易位 ,2次倒位造成了小熊猫与家猫的核型差异。我们的工作进一步证实了利用基因组高度重排的物种 (如 :狗 )的染色体特异探针与核型保守的物种 (如 :家猫、水貂、小熊猫 )进行比较染色体涂色研究 ,不但可以准确快速地鉴别物种进化过程中所发生的染色体间的结构重排 ,而且还可揭示染色体内的结构重组。We have established a comparative chromosome map between red panda ( Ailurus fulgens, 2n=36) and dog by chromosome painting with biotin labelled chromosome specific probes of the dog. Dog probes specific for the 38 automates delineated 71 homologous segments in the metaphase chromosomes of red panda. Of the 38 autosomal paints, 18 probes each delineated one homologous segment in red panda genome, while the other 20 ones each detected two to five homologous segments. The dog X chromosome specific paint delineated the whole X chromosome of the red panda. The results indicate that at least 28 fissions (breaks), 49 fusions and 4 inversions were needed to 'convert' the dog karyotype to that of the red panda, suggesting that extensive chromosome rearrangements differentiate the karyotypes of red panda and dog. Based on the established comparative chromosome homologies of dog and domestic cat, we could infer that there were 26 segments of conserved synteny between red panda and domestic cat. Comparative analysis of the distribution patterns of conserved segments defined by dog paints in red panda and domestic cat genomes revealed at least 2 cryptic inversions in two large chromosomal regions of conserved synteny between red panda and domestic cat. The karyotype of red panda shows high degree of homology with that of domestic cat.

关 键 词：小熊猫 狗 家猫 比较染色体涂色 核型进化 

分 类 号：Q953.3[生物学—动物学]