Flexibility in the order of action and in the enzymology of the nuclease, polymerases, and ligase of vertebrate nonhomologous DNA end joining: relevance to cancer, aging,and the immune system

• 来源期刊: 细胞研究（英文版）
• 年，卷（期）: 2008,（1）
• 页码范围: 125-133
• 页数: 9页
• 语种: 英文
• DOI: 10.1038/cr.2007.108

摘要

Nonhomologous DNA end joining (NHEJ) is the primary pathway for repair of double-strand DNA breaks in hu-man cells and in multicellular eukaryotes. The causes of double-strand breaks often fragment the DNA at the site of damage, resulting in the loss of information there. NHEJ does not restore the lost information and may resect ad-ditional nucleotides during the repair process. The ability to repair a wide range of overhang and damage configura-tions reflects the flexibility of the nuclease, polymerases, and ligase of NHEJ. The flexibility of the individual com-ponents also explains the large number of ways in which NHEJ can repair any given pair of DNA ends. The loss of information locally at sites of NHEJ repair may contribute to cancer and aging, but the action by NHEJ ensures that entire segments of chromosomes are not lost.