Skirball Institute of Biomolecular Medicine, Department of Cell Biology, NYU Langone Medical Center, New York, NY 10016, USA; Helen L. and Martin S. Kimmel Center for Biology and Medicine, NYU Langone Medical Center, New York, NY 10016, USA; Laura and Isaac Perlmutter Cancer Center, NYU Langone Medical Center, New York, NY 10016, USA; Sanford I. Weill Department of Medicine, Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10021, USA.
Skirball Institute of Biomolecular Medicine, Department of Cell Biology, NYU Langone Medical Center, New York, NY 10016, USA; Helen L. and Martin S. Kimmel Center for Biology and Medicine, NYU Langone Medical Center, New York, NY 10016, USA; Department of Biochemistry and Molecular Pharmacology, NYU Langone Medical Center, New York, NY 10016, USA.
Cell Rep. 2020 Mar 17;30(11):3597-3604.e3. doi: 10.1016/j.celrep.2020.02.073.
Cultured pluripotent cells accumulate detrimental chromatin alterations, including DNA methylation changes at imprinted genes known as loss of imprinting (LOI). Although the occurrence of LOI is considered a stochastic phenomenon, here we document a genetic determinant that segregates mouse pluripotent cells into stable and unstable cell lines. Unstable lines exhibit hypermethylation at Dlk1-Dio3 and other imprinted loci, in addition to impaired developmental potential. Stimulation of demethylases by ascorbic acid prevents LOI and loss of developmental potential. Susceptibility to LOI greatly differs between commonly used mouse strains, which we use to map a causal region on chromosome 13 with quantitative trait locus (QTL) analysis. Our observations identify a strong genetic determinant of locus-specific chromatin abnormalities in pluripotent cells and provide a non-invasive way to suppress them. This highlights the importance of considering genetics in conjunction with culture conditions for assuring the quality of pluripotent cells for biomedical applications.
培养的多能细胞会积累有害的染色质改变，包括印记基因的 DNA 甲基化变化，即印记丢失（LOI）。虽然 LOI 的发生被认为是一种随机现象，但在这里我们记录了一个遗传决定因素，它将小鼠多能细胞分为稳定和不稳定的细胞系。不稳定的细胞系在 Dlk1-Dio3 和其他印记基因座表现出过度甲基化，此外还表现出发育潜能受损。通过抗坏血酸刺激去甲基化酶可防止 LOI 和发育潜能丧失。LOI 的易感性在常用的小鼠品系之间差异很大，我们使用这些品系进行染色体 13 上的数量性状基因座（QTL）分析，以定位因果区域。我们的观察结果确定了多能细胞中特定基因座染色质异常的一个强有力的遗传决定因素，并提供了一种非侵入性的抑制它们的方法。这突出表明，在保证多能细胞用于生物医学应用的质量时，必须结合培养条件考虑遗传学。
