Germline Utx mutation as a model for transgenerational epigenetic inheritance

项目总结 雄配子将父系的基因组传递给下一代。同时，它们还携带 在受精时传递给受精卵的表观遗传信息。一个主要的悬而未决的问题是，这是否 遗传表观遗传信息影响后代的基因表达、表型和疾病易感性。 我们发现敲除小鼠雄性生殖系中的染色质调节基因UTX会导致 子代存活率降低，肿瘤形成率增加，即使子代本身不是这样 携带UTX突变。这项提议将检验以下假设：雄性生殖细胞中UTX的丢失导致 配子的表观遗传学变化在受精后改变基因表达并最终导致 在后代中观察到肿瘤易感性增加。具体地说，这里提出的实验将检验 组蛋白修饰、DNA甲基化和基因表达在发育和发育中的全基因组变化 UTX条件敲除的成熟雄配子(目标1)；评估基因表达和表型效应 在植入前和围产期的下一代胚胎中(目标2)；并界定 子代发育和成熟生殖细胞中组蛋白修饰、DNA甲基化和基因表达 以确定这些变化是否可以跨越多代人(目标3)。 这项研究的最终目的是了解在发育和基因调控状态方面的变化 哺乳动物雄性生殖细胞可以影响后代的表型和疾病。在过去，这个问题 主要通过使用化学或营养暴露来操纵父亲的环境来解决， 它们很难精确控制。相反，这项研究将采用简单、明确和高度的 可用于产生种系表观遗传变化的可重复的遗传操作。建议数 实验将阐明一种新的机制，即表观遗传失调对雄配子的影响 NICHD的一个优先领域--男性不育。这一结果还将为非遗传性疾病建立一种新的机制 疾病易感性的遗传，对常见疾病的病因和流行病学具有广泛的影响 癌症和糖尿病等疾病。

PROJECT SUMMARY Male gametes transmit the paternal genome to the next generation. At the same time, they also carry epigenetic information that is passed to the zygote at fertilization. A major unanswered question is whether this inherited epigenetic information influences gene expression, phenotype, and disease susceptibility in offspring. We have found that knocking out the chromatin regulator gene Utx in the mouse male germ line leads to reduced survival and increased rates of tumor formation in offspring, even when offspring do not themselves carry a Utx mutation. This proposal will test the hypothesis that loss of Utx in male germ cells induces epigenetic changes in the gametes that alter gene expression after fertilization and ultimately result in the increased tumor susceptibility observed in offspring. Specifically, the experiments proposed here will examine genome-wide changes in histone modification, DNA methylation, and gene expression in developing and mature male gametes of Utx conditional knockouts (Aim 1); evaluate gene expression and phenotypic effects in embryos of the next generation at the preimplantation and perinatal stages (Aim 2); and define changes in histone modification, DNA methylation, and gene expression in developing and mature germ cells of offspring in order to determine if these changes can persist across multiple generations (Aim 3). The ultimate goal of this study is to understand how changes in the development and gene regulatory state of mammalian male germ cells can impact phenotype and disease in progeny. In the past, this question has been addressed primarily by manipulating the paternal environment using chemical or nutritional exposures, which are difficult to control precisely. In contrast, this study will employ a simple, well-defined and highly reproducible genetic manipulation that can be used to generate germline epigenetic changes. The proposed experiments will elucidate a new mechanism by which epigenetic misregulation in male gametes can contribute to male infertility, a priority area for NICHD. The results will also frame a new mechanism for non-genetic inheritance of disease susceptibility, with broad implications for the etiology and epidemiology of common diseases such as cancer and diabetes.