Reprogrammed pluripotent stem cells (PSCs) are valuable for research and potentially for cell replacement therapy. However, only a fraction of reprogrammed PSCs are developmentally competent. Genomic stability and accurate DNA synthesis are fundamental for cell development and critical for safety. We analyzed whether defects in DNA replication contribute to genomic instability and the diverse differentiation potentials of reprogrammed PSCs. Using a unique single-molecule approach, we visualized DNA replication in isogenic PSCs generated by different reprogramming approaches, either somatic cell nuclear transfer (NT-hESCs) or with defined factors (iPSCs). In PSCs with lower differentiation potential, DNA replication was incompletely reprogrammed, and genomic instability increased during replicative stress. Reprogramming of DNA replication did not correlate with DNA methylation. Instead, fewer replication origins and a higher frequency of DNA breaks in PSCs with incompletely reprogrammed DNA replication were found. Given the impact of error-free DNA synthesis on the genomic integrity and differentiation proficiency of PSCs, analyzing DNA replication may be a useful quality control tool.

中文翻译：

---

具有低分化潜力的多能干细胞含有不完全重编程的DNA复制


重编程的多能干细胞（PSC）对于研究很有价值，并且有可能用于细胞替代疗法。然而，只有一小部分经过重编程的 PSC 具有发育能力。基因组稳定性和准确的 DNA 合成是细胞发育的基础，也是安全的关键。我们分析了 DNA 复制缺陷是否会导致基因组不稳定以及重编程 PSC 的多样化分化潜力。使用独特的单分子方法，我们可视化了通过不同重编程方法（体细胞核移植（NT-hESC）或具有特定因子（iPSC））生成的同基因 PSC 中的 DNA 复制。在分化潜力较低的 PSC 中，DNA 复制不完全重编程，并且在复制应激期间基因组不稳定性增加。 DNA 复制的重编程与 DNA 甲基化无关。相反，在DNA复制不完全重编程的PSC中发现了更少的复制起点和更高的DNA断裂频率。考虑到无差错 DNA 合成对 PSC 基因组完整性和分化能力的影响，分析 DNA 复制可能是一种有用的质量控制工具。