Mechanisms underlying sex-dependent pregnancy outcomes caused by fetal and maternal genomic instability

不良妊娠结局可能是几个因素缺陷的结果，如胎儿或母体缺陷 遗传、环境暴露、子宫功能障碍、先兆子痫、营养、感染、炎症和 胎盘功能不全。从滋养外胚层前体发育成健康的胎盘使适当 胎儿和母亲之间的营养、气体和废物交换。此外，母体和胎盘-固有的 必须控制界面的炎症，以保护胎儿。这个项目解决了基因组如何 卵子发生和胚胎发生过程中的不稳定性(GIN)可导致性二型妊娠结局， 以及胎盘如何可能特别容易受到这种情况的影响。对这一点的研究被低估了 导致不良妊娠结局的原因是发现雌性小鼠胚胎戏剧性地 当携带某些DNA复制或修复基因的突变时，更容易致死。合而为一 这样的模型将在这个项目中使用，女性偏见的致命性是由于易感性增加的 而男性胚胎则受到睾酮抗炎作用的保护。 初步数据显示，胎盘是导致胚胎死亡的敏感组织。值得注意的是， 这种性别偏见的致命性只有在大坝也具有杜松子酒基因的情况下才会发生。该项目的目标是 了解杜松子酒致死性炎症的组织(S)、细胞和机制。这将是 利用小鼠遗传学、基因组学和胚胎操作的力量完成的。目标一号将测试 胎盘、胚胎或两者都是女性偏向致命性疾病的原因。我们假设这个高度的 多倍体滋养层巨细胞可能对受损的DNA复制和杜松子酒特别敏感， 引发先天炎症。目标2解决为什么卵子必须来自高杜松子酒的母亲才能发生性行为 倾向于发生在携带突变致死基因的胎儿中。初步实验表明，这样的大坝 产生带有受损线粒体的卵母细胞，这一假设将用线粒体进行验证 增强和组学分析。目标3试图确定致死胚胎的分子基础 炎症，重点是先天免疫的触发因素。基因和分子分析的结合将会 被用来检验这一假设，即核GIN导致线粒体RNA和DNA泄漏，激活一种 刺激炎症驱动干扰素基因转录的途径(S)。 总体而言，如果成功，结果将与解释和处理个别反复发作的病例有关。 妊娠丢失可能与妊娠期间的内源性炎症有关，并提供了对 导致不良妊娠结局的机制未得到充分认识，包括流产和宫内 发育迟缓。

Adverse pregnancy outcomes can be the consequence of defects in several factors, such fetal or maternal genetics, environmental exposures, uterine dysfunction, preeclampsia, nutrition, infection, inflammation, and placental insufficiency. Development of a healthy placenta from trophectoderm precursors enables proper nutrient, gas and waste exchange between the fetus and mother. Additionally, maternal and placenta-intrinsic inflammation at the interface must be controlled to protect the fetus. This project addresses how genomic instability (GIN) during oogenesis and embryogenesis can cause sexually dimorphic pregnancy outcomes, and how the placenta may be especially susceptible to this condition. Research into this underappreciated cause of adverse pregnancy outcomes is motivated by findings that female mouse embryos are dramatically more prone to lethality when bearing certain GIN-causing mutations of DNA replication or repair genes. In one such model that will be utilized in this project, the female-biased lethality was due to increased susceptibility to inflammation, whereas male embryos were protected by the anti-inflammatory effects of testosterone. Preliminary data implicate the placenta as the sensitive tissue underlying the embryonic death. Remarkably, this sex-biased lethality occurred only if the dam also had a GIN genotype. The goals of this project are to understand the tissue(s), cells, and mechanisms driving GIN-induced lethal inflammation. This will be accomplished using the power of mouse genetics, genomics, and embryo manipulation. Aim 1 will test whether the placenta, the embryo, or both, are responsible for female-biased lethality. We hypothesize that the highly polyploid trophoblast giant cells may be especially sensitive to compromised DNA replication and GIN, triggering innate inflammation. Aim 2 addresses why oocytes must come from high GIN mothers for the sex bias to occur in fetuses bearing the mutant lethal genotype. Preliminary experiments implicate that such dams produce oocytes with compromised mitochondria, and this hypothesis will be tested using mitochondrial augmentation and -omics analyses. Aim 3 seeks to identify the molecular basis of lethal embryonic inflammation, with a focus on triggers of innate immunity. A combination of genetic and molecular assays will be used to test the hypothesis that nuclear GIN leads to mitochondrial RNA and DNA leakage, activating a pathway(s) that stimulates transcription of inflammation-driving interferon genes. Overall, if successful, the results will be relevant for interpreting and addressing individual cases of recurrent pregnancy loss that may have a basis in intrinsic inflammation during gestation, and provide insights into underappreciated mechanisms causing adverse pregnancy outcomes including miscarriage and intrauterine growth retardation.