A new light on DNA replication from the inactive X chromosome

作者：Aladjem Mirit I^*; Fu Haiqing

来源：BioEssays, 2014, 36(6): 591-597.

DOI：10.1002/bies.201400021

• cell cycle
• chromatin
• DNA replication
• epigenetics
• inactive X chromosome

While large portions of the mammalian genome are known to replicate sequentially in a distinct, tissue-specific order, recent studies suggest that the inactive X chromosome is duplicated rapidly via random, synchronous DNA synthesis at numerous adjacent regions. The rapid duplication of the inactive X chromosome was observed in high-resolution studies visualizing DNA replication patterns in the nucleus, and by allele-specific DNA sequencing studies measuring the extent of DNA synthesis. These studies conclude that inactive X chromosomes complete replication earlier than previously thought and suggest that the strict order of DNA replication detected in the majority of genomic regions is not preserved in non-transcribed, silent chromatin. These observations alter current concepts about the regulation of DNA replication in non-transcribed portions of the genome in general and in the inactive X-chromosome in particular.

• 出版日期2014-6