Uncoupling of DNA Replication and Centrosome Duplication Cycles Is a Primary Cause of Haploid Instability in Mammalian Somatic Cells
Uncoupling of DNA Replication and Centrosome Duplication Cycles Is a Primary Cause of Haploid Instability in Mammalian Somatic Cells
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DOI：
10.3389/fcell.2020.00721
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发表时间：
2020-05
影响因子：
5.5
通讯作者：
Koya Yoshizawa;Kan Yaguchi;Ryota Uehara
中科院分区：
文献类型：
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作者：
Koya Yoshizawa;Kan Yaguchi;Ryota Uehara
哺乳动物单倍体体细胞不稳定并且容易二倍化，但单倍体不稳定的原因仍然很大程度上未知。此前，我们发现哺乳动物单倍体体细胞由于DNA复制和中心体复制周期的解偶联而遭受慢性中心体损失。然而，由于缺乏恢复 DNA 复制和中心体复制之间耦合的方法，我们无法研究单倍体相关中心体丢失对单倍体不稳定性的潜在贡献。在这项研究中，我们开发了一种实验方法，允许通过 G1/S 期的长期延长来重新偶联 DNA 和中心体周期，而不会使用胸苷处理/释放周期损害细胞增殖。 G1/S 的慢性延长恢复了正常的有丝分裂中心体数量和有丝分裂控制，大大提高了 HAP1 细胞中单倍体状态的稳定性。当 cdk2 在延长的 G1/S 期间受到抑制时，或者当早期 G1 而不是 G1/S 长期延长时，单倍体状态的稳定性就会受到损害，这表明单倍体稳定性需要 DNA 和中心体周期的耦合，而不是细胞周期的普遍延长。我们的数据表明，中心体和DNA循环解偶联引起的慢性中心粒丢失是单倍体体细胞基因组不稳定的直接原因，并且还证明了通过哺乳动物体细胞中DNA和中心体循环之间的人工协调来调节单倍体稳定性的可行性。
Mammalian haploid somatic cells are unstable and prone to diploidize, but the cause of haploid instability remains largely unknown. Previously, we found that mammalian haploid somatic cells suffer chronic centrosome loss stemming from the uncoupling of DNA replication and centrosome duplication cycles. However, the lack of methodology to restore the coupling between DNA replication and centrosome duplication has precluded us from investigating the potential contribution of the haploidy-linked centrosome loss to haploid instability. In this study, we developed an experimental method that allows the re-coupling of DNA and centrosome cycles through the chronic extension of the G1/S phase without compromising cell proliferation using thymidine treatment/release cycles. Chronic extension of G1/S restored normal mitotic centrosome number and mitotic control, substantially improving the stability of the haploid state in HAP1 cells. Stabilization of the haploid state was compromised when cdk2 was inhibited during the extended G1/S, or when early G1 was chronically extended instead of G1/S, showing that the coupling of DNA and centrosome cycles rather than a general extension of the cell cycle is required for haploid stability. Our data indicate the chronic centriole loss arising from the uncoupling of centrosome and DNA cycles as a direct cause of genome instability in haploid somatic cells, and also demonstrate the feasibility of modulation of haploid stability through artificial coordination between DNA and centrosome cycles in mammalian somatic cells.