Controlling FKBP51 for the treatment of PTSD

美国退伍军人患精神症状和精神障碍的风险增加 与平民百姓相比。长期以来，下丘脑-垂体-肾上腺(HPA)轴 与压力引起的精神障碍有关。51 kDa FK506结合蛋白FKBP51 与90 kDa热休克蛋白(Hsp90)一起，调节类固醇激素复合体的活性 百帕轴和其他级联。FKBP51-伴侣复合体减慢HPA的反应 轴向循环应激荷尔蒙。最近，人们发现，有天然的 基因中以单核苷酸多态(SNPs)形式出现的遗传变异 编码FKBP51、FKBP5，导致DNA去甲基化和FKBP5表达增加。 FKBP5的水平在压力和衰老过程中也被证明是通过类似的机制增加的。这个 促进去甲基化的单核苷酸多态也与压力引起的风险增加有关 精神病理学，如创伤后应激障碍(PTSD)和严重抑郁障碍 (MDD)。重要的是，缺乏FKBP5的小鼠受到保护，免受与 情绪障碍。我们现在已经产生了一种新的过度表达的转基因小鼠模型 FKBP5在前脑。我们还创造了一种新的细胞系，它可以荧光地过度表达 标签为FKBP51，可以很容易地实时跟踪。使用这些工具，我们将测试 假设降低小鼠FKBP51水平的机制将提高对 压力导致的行为缺陷。这项提案将集中在1)提高FKBP51的税率 通过伴侣调节的蛋白质周转和通过破坏蛋白质降低FKBP5水平 通过使用反义寡核苷酸(ASO)进行翻译和2)提高我们对 FKBP51是如何导致应激诱导的行为缺陷的。首先，我们将增加FKBP51 通过伴侣蛋白调节来降解。因为我们知道伴侣蛋白，比如 HSP90对蛋白质分类至关重要，我们知道FKBP51与HSP90一起调节类固醇 激素复合体，我们假设有一个更大的伴侣蛋白谱系，它 调节FKBP51的周转。使用表达荧光标记的FKBP51的细胞，我们将调制 使用shRNA的蛋白质伴侣。我们将通过以下方式确定新的蛋白质伴侣-FKBP51相互作用 测量FKBP51半衰期的变化。我们还将确定FKBP51的运价和路线 并评估各种细胞应激源对FKBP51稳定性的影响。接下来，我们将 测试我们的铅FKBP5特异性ASO对野生型小鼠大脑中FKBP5的降低效果 暴露在压力之下。对压力引起的行为缺陷的保护将被评估。最后，在一个 努力评估FKBP51对退伍军人报告的最常见创伤后应激障碍症状的影响， 我们将确定FKBP51在调节睡眠中断中的作用，睡眠中断是由 昼夜节律不同步。我们将确定缺乏或过度表达FKBP51的小鼠是否有 基本或对压力的反应改变了昼夜节律的同步性。这些研究的结果可能 揭示FKBP51靶向治疗可能有益于逆转昼夜节律紊乱 在创伤后应激障碍以及其他精神障碍和衰老中常见。如果这真的是 在这种情况下，昼夜节律性可以作为强健读数来衡量 FKBP51-开发的靶向疗法。

U.S. Veterans are at increased risk for developing psychiatric symptoms and disorders compared to the civilian population. The hypothalamic-pituitary-adrenal (HPA) axis has long been linked to stress-induced psychiatric disorders. The 51kDa FK506-binding protein, FKBP51, together with the 90kDa heat shock protein (Hsp90), regulates the activity of steroid hormone complexes in the HPA axis and other cascades. The FKBP51-chaperone complex slows the response of the HPA axis to circulating stress hormones. Recently, it has been discovered that there are naturally occurring genetic variants in the form of single nucleotide polymorphisms (SNPs) in the gene encoding FKBP51, FKBP5, that cause DNA demethylation and increased expression of FKBP5. FKBP5 levels have been shown to increase during stress and aging by a similar mechanism. The SNPs that promote demethylation are also associated with increased risk for stress-induced psychopathologies such as post-traumatic stress disorder (PTSD) and major depressive disorder (MDD). Importantly, mice lacking Fkbp5 are protected from behavioral phenotypes associated with mood disorders. We have now generated a novel transgenic mouse model that overexpresses FKBP5 in the forebrain. We have also generated a novel cell line which overexpresses fluorescently labelled FKBP51, which can be easily tracked in real time. With these tools, we will test the hypothesis that mechanisms which decrease the levels of FKBP51 in mice will improve resiliency to stress-induced behavioral deficits. This proposal will focus on 1) increasing the rate of FKBP51 protein turnover through chaperone regulation and decreasing FKBP5 levels by disrupting protein translation through use of antisense oligonucleotides (ASOs) and 2) improving our understanding of how FKBP51 contributes to stress-induced behavioral deficits. First, we will increase FKBP51 degradation through chaperone protein modulation. Since we know that chaperone proteins, like Hsp90, are vital for protein triage and we know that FKBP51 works with Hsp90 to regulate steroid hormone complexes, we hypothesize that there is a larger chaperone protein repertoire which regulates FKBP51 turnover. Using cells expressing fluorescently tagged FKBP51, we will modulate protein chaperones using shRNA. We will identify novel protein chaperone-FKBP51 interactions by measuring changes in FKBP51 half-life. We will also determine the rate and route of FKBP51 turnover as well as assess the impact of various cellular stressors on FKBP51 stability. Next, we will test our lead Fkbp5-specific ASOs for their efficacy in reducing Fkbp5 in the brain of wild-type mice exposed to stress. Protection from stress-induced behavioral deficits will be evaluated. Lastly, in an effort to evaluate the impact of FKBP51 on the most common PTSD symptom reported by Veterans, we will determine the role of FKBP51 in the regulation of sleep disruption, which is caused by circadian desynchrony. We will determine whether mice lacking or overexpressing FKBP51 have altered circadian synchrony basally or in response to stress. The results from these studies may reveal that FKBP51-targeted therapies could be beneficial for reversing the circadian disruption that is commonly found in PTSD as well as in other psychiatric disorders and aging. If this is in fact the case, then circadian rhythmicity could be measured as a robust readout for the effectiveness of any FKBP51-targeted therapies that are developed.