Impact of Egg Quality on Gene Expression and Behavior

描述(申请人提供)：现在，卵子捐赠研究清楚地认识到，是卵子而不是生殖道是生育力下降或不育的原因。值得注意的是，构成高质量鸡蛋的分子基础基本上是未知的。特定目的1将通过使用抑制消减杂交来鉴定在减数分裂和发育能力强的高质量小鼠卵子中差异表达的基因，来检验特定的基因表达模式表征高质量卵子的假设。这些基因将被用来构建一种“卵母细胞芯片”，用来确定一组特定的这些基因是否在发育能力受损的卵母细胞中错误表达或不适当表达，例如，在体外培养过程中发育的卵母细胞；来自小腔卵泡的卵母细胞；从过度刺激的小鼠获得的卵母细胞；以及从老龄小鼠获得的卵母细胞。成人疾病的胎儿起源假说认为，成人中的特定疾病是胎儿在子宫内适应母亲营养不良或营养不良的结果。这一假设可能会延伸到植入前阶段，因为在这一阶段减少大鼠的蛋白质摄入量会导致这种长期的变化，而植入前胚胎的培养会导致后代行为发生变化。《特定目标2》将通过用一系列行为分析来分析这些后代，来检验这一假说，即低质量的卵子会导致表现出行为紊乱的后代。用辅助生殖技术(ART)治疗人类不孕不育需要胚胎培养，这可能会导致基因表达的变化。即使是用于抗逆转录病毒治疗的高质量卵子(以及由此产生的植入前胚胎)，也可能仅仅因为胚胎培养条件而面临风险。具体目标3将测试这样一个假设，即改变培养条件可以减轻胚胎培养对后代基因表达和行为中观察到的与培养相关的扰动的影响。这些实验的结果将建立卵子质量的分子基础，并将提供有关低质量卵子对后代行为的影响以及ART程序对基因表达和行为的影响的关键信息。

DESCRIPTION (provided by applicant): It is now clearly recognized from egg donation studies that it is the egg and not the reproductive tract that is the cause of reduced fertility or infertility. Remarkably, the molecular underpinnings of what constitutes an egg of "high" quality are essentially unknown. Specific Aim 1 will test the hypothesis that a specific pattern of gene expression characterizes eggs of high quality by using suppression subtractive hybridization to identify genes that are differentially expressed in meiotically and developmentally competent high quality mouse eggs. These genes will be used to construct an "oocyte chip" that will be used to ascertain if a specific set of these genes is mis-expressed, or inappropriately expressed, in oocytes whose developmental competence is compromised, e.g., oocytes that develop during in vitro culture; oocytes derived from small antral follicles, oocytes obtained from hyperstimulated mice, and oocytes obtained from aged mice. The Fetal Origins of Adult Disease hypothesis posits that specific diseases in the adult are the result of the fetus's adaptations in utero to maternal under nutrition or malnutrition. This hypothesis may extend to the preimplantation stage, since reducing protein intake during this time in the rat results in such long-term changes, and the culturing of preimplantation embryos leads to offspring that exhibit altered behavior. Specific Aim 2 will test the hypothesis that low quality eggs give rise to offspring that exhibit perturbations in behavior by analyzing these offspring with a battery of behavioral assays. Treatment of human infertility with Assisted Reproductive Technology (ART) entails embryo culture that can result in changes in gene expression. Even eggs of high quality (and the resulting preimplantation embryos) that are used in ART may be at risk simply due to embryo culture conditions. Specific Aim 3 will test the hypothesis that modifications of culture conditions can alleviate the effect of embryo culture on the culture-associated perturbations observed in gene expression and behavior in the offspring. Results of these experiments will establish the molecular basis of egg quality and will provide critical information regarding the effect on behavior in offspring derived from low quality eggs, as well as the effect of ART procedures on gene expression and behavior.