Hyrien Olivier
Institut de Biologie de l'Ecole Normale Supérieure, Centre National de la Recherche Scientifique UMR8197 and Institut National de la Santé et de la Recherche Médicale U1024, 75005 Paris, France
J Cell Biol. 2015 Jan 19;208(2):147-60. doi: 10.1083/jcb.201407004.
Replication of mammalian genomes starts at sites termed replication origins, which historically have been difficult to locate as a result of large genome sizes, limited power of genetic identification schemes, and rareness and fragility of initiation intermediates. However, origins are now mapped by the thousands using microarrays and sequencing techniques. Independent studies show modest concordance, suggesting that mammalian origins can form at any DNA sequence but are suppressed by read-through transcription or that they can overlap the 5' end or even the entire gene. These results require a critical reevaluation of whether origins form at specific DNA elements and/or epigenetic signals or require no such determinants.
哺乳动物基因组的复制起始于被称为复制起点的位点，由于基因组规模庞大、遗传识别方法的能力有限以及起始中间体的稀少和脆弱性，这些位点在历史上一直难以定位。然而，现在利用微阵列和测序技术已定位了数以千计的复制起点。独立研究显示出一定程度的一致性，这表明哺乳动物的复制起点可以在任何DNA序列处形成，但会受到通读转录的抑制，或者它们可能与5'端甚至整个基因重叠。这些结果需要对复制起点是在特定DNA元件和/或表观遗传信号处形成，还是不需要此类决定因素进行批判性的重新评估。
