Getting it done at the ends: Pif1 family DNA helicases and telomeres.
Getting it done at the ends: Pif1 family DNA helicases and telomeres.
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DOI：
10.1016/j.dnarep.2016.05.021
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发表时间：
2016-08
期刊：
影响因子：
3.8
通讯作者：
Zakian VA
中科院分区：
文献类型：
--
作者：
Geronimo CL;Zakian VA
广泛认识到，线性DNA分子的末端不能通过常规复制装置完全复制。不太为人所知的是，端粒DNA的半保守复制也给DNA复制带来了问题。这些问题可能源于端粒的非典型染色质结构，端粒DNA的GC丰富性使其易于形成DNA二级结构，以及由一条或两条DNA链的转录物形成的RNA-DNA杂交体。考虑到端粒的不同方面使其复制复杂化，多个DNA解旋酶促进端粒DNA的复制并不奇怪。本文综述了其中一类DNA解旋酶，即5′-3′ DNA解旋酶Pif 1家族。在芽殖酵母和裂殖酵母中，Pif 1家族解旋酶影响端粒DNA的端粒酶介导的和半保守的复制以及重组介导的端粒延长。
It is widely appreciated that the ends of linear DNA molecules cannot be fully replicated by the conventional replication apparatus. Less well known is that semi-conservative replication of telomeric DNA also presents problems for DNA replication. These problems likely arise from the atypical chromatin structure of telomeres, the GC-richness of telomeric DNA that makes it prone to forming DNA secondary structures, and from RNA-DNA hybrids, formed by transcripts of one or both DNA strands. Given the different aspects of telomeres that complicate their replication, it is not surprising that multiple DNA helicases promote replication of telomeric DNA. This review focuses on one such class of DNA helicases, the Pif1 family of 5′–3′ DNA helicases. In budding and fission yeasts, Pif1 family helicases impact both telomerase-mediated and semi-conservative replication of telomeric DNA as well as recombination-mediated telomere lengthening.