Instituto Nacional de Pesquisas da Amazônia, Coordenação de Biodiversidade, Laboratory of Animal Genetics, Av. André Araújo 2936, Petrópolis, Manaus CEP: 69067-375, AM, Brazil.
Institute for Applied Ecology, Faculty of Science and Technology, University of Canberra, Canberra, ACT 2616, Australia.
Genes (Basel). 2019 Apr 9;10(4):288. doi: 10.3390/genes10040288.
Amazonian puffing snakes ( Colubridae) are snakes widely distributed in the Neotropical region. However, chromosomal data are scarce in this group and, when available, are only limited to karyotype description using conventional staining. In this paper, we focused on the process of karyotype evolution and trends for sex chromosomes in two Amazonian Puffer Snakes ( and ). We performed an extensive karyotype characterization using conventional and molecular cytogenetic approaches. The karyotype of (presented here for the first time) exhibits a 2n = 36, similar to that previously described in . Both species have highly differentiated ZZ/ZW sex chromosomes, where the W chromosome is highly heterochromatic in but euchromatic in . Both W chromosomes are homologous between these species as revealed by cross-species comparative genomic hybridization, even with heterogeneous distributions of several repetitive sequences across their genomes, including on the Z and on the W chromosomes. Our study provides evidence that W chromosomes in these two species have shared ancestry.
亚马孙膨腹蛇（ Colubridae）是一种广泛分布于新热带地区的蛇类。然而，该类群的染色体数据非常有限，而且可用的数据仅局限于使用常规染色方法对核型进行描述。在本文中，我们专注于研究两种亚马孙膨腹蛇（ 和 ）的染色体进化过程和性染色体的演化趋势。我们使用常规和分子细胞遗传学方法对其进行了广泛的核型特征描述。 （本文首次报道）的核型为 2n = 36，与先前在 中描述的核型相似。这两个物种的 ZZ/ZW 性染色体高度分化，其中 W 染色体在 中高度异染色质化，但在 中是常染色质化的。通过种间比较基因组杂交揭示，这两个物种的两条 W 染色体是同源的，即使在它们的基因组中，包括在 Z 和 W 染色体上，有几个重复序列的不均匀分布。我们的研究提供了证据表明这两个物种的 W 染色体具有共同的祖先。
