The intersection of stress and environmental chemicals in germ cell reprogramming

项目摘要 这项提案的目标是确定接触无处不在的塑料和产前压力是如何相互作用的 赋予发育中的生殖细胞表观遗传学变化，以及这种变化如何导致生殖和新陈代谢 晚年生活中的表型，可能在后代中也是如此。大量研究涉及消费者和 农用化学品表现出的效应出现在个体的后代甚至孙子身上 在子宫中暴露。敏感期和表观遗传重编程之间的对应关系表明 生殖细胞的表观遗传学变化也参与其中。然而，由于大多数研究使用口服治疗 给药，化学物质和产前应激的影响很难消除。邻苯二甲酸盐是主要的 在加利福尼亚州100%的孕妇中检测到了家庭灰尘中的化学物质。我们的预赛 对小鼠的研究发现，在生殖细胞表观遗传学期间，产前暴露于两种不同的邻苯二甲酸盐 在每种情况下，编程都会减少对反转录转座子和生殖细胞发育的抑制 缺陷；我们实验室的证据表明，这是通过破坏piRNA途径而发生的，这 通过表观遗传和翻译后机制沉默内源性转座元件。在这 提案，我们将询问生物相关剂量的邻苯二甲酸酯和 妊娠早期应激对小鼠生殖细胞表观遗传状态的影响 后代的反转录转座子活性和生殖表型。Aim 1的研究将确定多早 妊娠应激和邻苯二甲酸盐暴露相互作用，改变胎儿生殖细胞的表观遗传状态，并 有可能继承那个州。这将解开压力和化学物质暴露的影响 在许多先前的研究中，伴随着口腔灌胃，具有可量化的分子读数以及测试潜力 直接和多代表观遗传失调的机制。目标2将检查表型 妊娠早期应激和邻苯二甲酸盐暴露对生殖细胞和女性生殖衰老的影响 在下一代。通过将成人生殖表型与胎儿暴露联系起来，这将开始 解开塑料和产前压力的影响。应激中关键节点的药理调控 反应途径可能会为高危妊娠妇女提供适当的治疗方法。 目标3将确定由早期妊娠引起的转座子插入导致的遗传中断的程度 应激和邻苯二甲酸盐在直接暴露的生殖细胞和后续世代。这些研究将确定 对基因组完整性构成最大风险的环境因素以及可能的药物疗法 这些影响。

PROJECT ABSTRACT The goal of this proposal is to establish how exposures to ubiquitous plastics and prenatal stress interact to confer epigenetic changes to developing germ cells, and how such changes lead to reproductive and metabolic phenotypes in later life and potentially in subsequent generations. Numerous studies involving consumer and agricultural chemicals demonstrate effects that appear in the progeny and even grandchildren of individuals exposed in utero. Correspondence between period of susceptibility and epigenetic reprogramming suggest that epigenetic changes to germ cells are involved. However, as the majority of studies utilize oral gavage for dosing, the effects of the chemical and prenatal stress are difficult to resolve. Phthalates are the major chemical in household dust and have been detected in 100% of pregnant women in California. Our preliminary studies in mice find that prenatal exposures to two different phthalates during the period of germ cell epigenetic programming leads in each case to decreased repression of retrotransposons and germ cell developmental defects; evidence from our lab suggests that this occurs through disruption of the piRNA pathway, which silences endogenous transposable elements through epigenetic and post-translational mechanisms. In this proposal, we will interrogate the combined and separate effects of biologically relevant doses of phthalate and early gestational stress on the epigenetic state of mouse germ cells and relate these changes to the extent of retrotransposon activity and reproductive phenotypes in the progeny. Studies in Aim 1 will determine how early gestational stress and phthalate exposure interact to alter the epigenetic state of fetal germ cells and the potential for inheritance of that state. This will disentangle the effects of stress and chemical exposure that accompany oral gavage in many prior studies with quantifiable, molecular readouts as well as testing potential mechanisms of direct and multigenerational epigenetic dysregulation. Aim 2 will examine phenotypic consequences of early gestational stress and phthalate exposure on germ cells and female reproductive aging in the next generation. By connecting adult reproductive phenotypes to fetal exposures, this will begin to disentangle the effects of plastics versus prenatal stress. Pharmacologic modulation of key nodes in the stress response pathway will potentially provide insight on appropriate therapies for women in high-risk pregnancies. Aim 3 will determine the extent of genetic disruptions via transposon insertions induced by early gestational stress and phthalates in directly exposed germ cells and subsequent generations. These studies will identify environmental factors that pose greatest risk to genomic integrity and potentially a drug therapy to mitigate those effects.