PDF(Pubmed)
Abstract：
Satellite DNA (satDNA) consists of sequences of DNA that form tandem repetitions across the genome, and it is notorious for its diversity and fast evolutionary rate. Despite its importance, satDNA has been only sporadically studied in reptile lineages. Here, we sequenced genomic DNA and PCR-amplified microdissected W chromosomes on the Illumina platform in order to characterize the monomers of satDNA from the Henkel\'s leaf-tailed gecko U. henkeli and to compare their topology by in situ hybridization in the karyotypes of the closely related Günther\'s flat-tail gecko U. guentheri and gold dust day gecko P. laticauda. We identified seventeen different satDNAs; twelve of them seem to accumulate in centromeres, telomeres and/or the W chromosome. Notably, centromeric and telomeric regions seem to share similar types of satDNAs, and we found two that seem to accumulate at both edges of all chromosomes in all three species. We speculate that the long-term stability of all-acrocentric karyotypes in geckos might be explained from the presence of specific satDNAs at the centromeric regions that are strong meiotic drivers, a hypothesis that should be further tested.
摘要：
卫星DNA（satDNA）由在整个基因组中形成串联重复的DNA序列组成，它以其多样性和快速进化速度而臭名昭著。尽管它很重要,仅在爬行动物谱系中对satDNA进行了零星研究。这里,我们在Illumina平台上对基因组DNA和PCR扩增的显微解剖的W染色体进行了测序，以表征汉高叶尾壁虎的satDNA单体，并通过原位杂交在密切相关的Günther的平尾壁虎和金尘日壁虎的核型中比较其拓扑结构。我们确定了十七个不同的satDNAs；其中十二个似乎在着丝粒中积累，端粒和/或W染色体。值得注意的是,着丝粒和端粒区域似乎共享类似类型的satDNA，我们发现了两个似乎在所有三个物种的所有染色体的两个边缘积累。我们推测壁虎中全顶心核型的长期稳定性可能是由于在着丝粒区域存在特定的satDNAs，这些satDNAs是强大的减数分裂驱动因素，一个应该进一步检验的假设。
