Department of Agricultural Biotechnology and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-742, Korea.
BMB Rep. 2013 Jun;46(6):310-5. doi: 10.5483/bmbrep.2013.46.6.185.
The gene order on the X chromosome of eutherians is generally highly conserved, although an increase in the rate of rearrangement has been reported in the rodent lineage. Conservation of the X chromosome is thought to be caused by selection related to maintenance of dosage compensation. However, we herein reveal that the cattle (Btau4.0) lineage has experienced a strong increase in the rate of X-chromosome rearrangement, much stronger than that previously reported for rodents. We also show that this increase is not matched by a similar increase on the autosomes and cannot be explained by assembly errors. Furthermore, we compared the difference in two cattle genome assemblies: Btau4.0 and Btau6.0 (Bos taurus UMD3.1). The results showed a discrepancy between Btau4.0 and Btau6.0 cattle assembly version data, and we believe that Btau6.0 cattle assembly version data are not more reliable than Btau4.0.
真兽类 X 染色体上的基因顺序通常高度保守，尽管在啮齿动物谱系中已报道重排率增加。X 染色体的保守性被认为是与维持剂量补偿相关的选择所导致的。然而，我们在此揭示牛（Btau4.0）谱系经历了 X 染色体重排率的强烈增加，比以前报道的啮齿动物要强得多。我们还表明，这种增加与常染色体上的类似增加不匹配，不能用组装错误来解释。此外，我们比较了两个牛基因组组装之间的差异：Btau4.0 和 Btau6.0（Bos taurus UMD3.1）。结果表明 Btau4.0 和 Btau6.0 牛组装版本数据之间存在差异，我们认为 Btau6.0 牛组装版本数据并不比 Btau4.0 更可靠。
