Department of Histology and Cell Biology, Nagasaki University Graduate School of Biomedical Sciences, 1-12-4, Sakamoto, Nagasaki, 852-8523, Japan.
Histochem Cell Biol. 2020 Aug;154(2):123-134. doi: 10.1007/s00418-020-01900-x. Epub 2020 Jul 11.
Mammalian spermatogenesis is characterized by disproportionate germ cell apoptosis. The high frequency of apoptosis is considered a safety mechanism that serves to avoid unfavorable transmission of paternal aberrant genetic information to the offspring as well as elimination mechanism for removal of overproduced immature or damaged spermatogenic cells. The molecular mechanisms involved in the induction of germ cell apoptosis include both intrinsic mitochondrial Bcl-2/Bax and extrinsic Fas/FasL pathways. However, little is known about the nuclear trigger of those systems. Recent studies indicate that epigenomes are essential in the regulation of gene expression through remodeling of the chromatin structure, and are genome-like transmission materials that reflect the effects of various environmental factors. In spermatogenesis, epigenetic errors can act as the trigger for elimination of germ cells with abnormal chromatin structure, abnormal gene expression and/or morphological defects (disordered differentiation). In this review, we focus on the relationship between global changes in epigenetic parameters and germ cell apoptosis in mice and other mammals.
哺乳动物的精子发生过程以不成比例的生殖细胞凋亡为特征。高频率的凋亡被认为是一种安全机制，有助于避免父系异常遗传信息向后代的不利传递，以及消除多余的不成熟或受损的生殖细胞的清除机制。诱导生殖细胞凋亡的分子机制包括内在的线粒体 Bcl-2/Bax 和外在的 Fas/FasL 途径。然而，对于这些系统的核触发因素知之甚少。最近的研究表明，表观基因组通过重塑染色质结构，在调节基因表达方面至关重要，并且是类似基因组的传递物质，反映了各种环境因素的影响。在精子发生过程中，表观遗传错误可以作为消除具有异常染色质结构、异常基因表达和/或形态缺陷（分化紊乱）的生殖细胞的触发因素。在这篇综述中，我们重点讨论了表观遗传参数的全局变化与小鼠和其他哺乳动物生殖细胞凋亡之间的关系。
