Genetics of Male Fertility Group, Unitat de Biologia Cel·lular (Facultat de Biociències), Universitat Autònoma de Barcelona, Bellaterra (Cerdanyola del Vallès), Spain.
GenIntegral, Barcelona, Spain.
Adv Exp Med Biol. 2019;1166:57-74. doi: 10.1007/978-3-030-21664-1_4.
Epigenetic information refers to heritable changes in gene expression that occur without modifications at the DNA sequence level. These changes are orchestrated by different epigenetic mechanisms such as DNA methylation, posttranslational modifications of histones, and the presence of noncoding RNAs. Epigenetic information regulates chromatin structure to confer cell-specific gene expression.The sperm epigenome is the result of three periods of global resetting during men's life. Germ cell epigenome reprogramming is designed to allow cell totipotency and to prevent the transmission of epimutations via spermatozoa. At the end of these reprogramming events, the sperm epigenome has a very specific epigenetic pattern that is a footprint of past reprogramming events and has an influence on embryo development.Several data demonstrate that not all regions of the epigenome are erased during the reprogramming periods, suggesting the transmission of epigenetic information from fathers to offspring via spermatozoa. Moreover, it is becoming increasingly clear that the sperm epigenome is sensitive to environmental factors during the process of gamete differentiation, suggesting the plasticity of the sperm epigenetic signature according to the circumstances of the individual's life.In this chapter, we provided strong evidences about the association between variations of the sperm epigenome and the exposure to environmental factors. Moreover, we will present data about how epigenetic mechanisms are candidates for transferring paternal environmental information to offspring.
表观遗传信息是指基因表达的可遗传变化，而这些变化发生在 DNA 序列水平没有改变的情况下。这些变化是由不同的表观遗传机制调控的，如 DNA 甲基化、组蛋白的翻译后修饰以及非编码 RNA 的存在。表观遗传信息调节染色质结构，赋予细胞特异性基因表达。精子表观基因组是男性一生中三个全局重置期的结果。生殖细胞表观基因组重编程旨在允许细胞全能性，并防止通过精子传递表观突变。在这些重编程事件结束时，精子表观基因组具有非常特定的表观遗传模式，这是过去重编程事件的足迹，并对胚胎发育有影响。有几项数据表明，在重编程期间并非所有的表观基因组区域都被清除，这表明来自父亲的表观遗传信息通过精子传递给后代。此外，越来越明显的是，精子表观基因组在配子分化过程中对环境因素敏感，这表明根据个体生活的情况，精子表观遗传特征具有可塑性。在这一章中，我们提供了强有力的证据表明精子表观基因组的变异与暴露于环境因素之间存在关联。此外，我们还将介绍有关表观遗传机制如何成为将父系环境信息传递给后代的候选因素的数据。
