Pleiotropic xenobiotics can trigger dynamic alterations in mammalian chromatin structure and function but many of these are likely non-adverse and simply reflect short-term changes in DNA transactions underlying normal homeostatic, adaptive and protective cellular responses. However, it is plausible that a subset of xenobiotic-induced perturbations of somatic tissue or germline epigenomes result in delayed-onset and long-lasting adverse effects, in particular if they occur during critical stages of growth and development. These could include reprogramming, dedifferentiation, uncontrolled growth, and cumulative toxicity effects through molecular memory of prior xenobiotic exposures or altered susceptibility to subsequent xenobiotic exposures. Here we discuss the current evidence for epigenetic mechanisms underlying latent responses to xenobiotics, and the potential for identifying molecular epigenetic changes that are prodromal to overt morphologic or functional toxicity phenotypes.

中文翻译：

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对异源生物潜在反应的染色质动力学

多效异源生物可以触发哺乳动物染色质结构和功能的动态改变，但其中许多可能是不利的，它们只是反映了正常体内稳态，适应性和保护性细胞反应基础上的DNA交易的短期变化。但是，有可能的是，异种生物引起的体细胞组织或种系表观基因组扰动的一个子集会导致延迟发作和长期不良影响，特别是如果它们发生在生长和发育的关键阶段。这些可能包括重新编程，去分化，不受控制的生长以及通过先前异种生物暴露的分子记忆或对随后异种生物暴露的敏感性改变的累积毒性效应。在这里，我们讨论了对异源生物潜在反应的表观遗传机制的最新证据，