CRE rat for Psychiatric Disorders

据估计，成瘾及其相关成本：犯罪，家庭暴力和虐待儿童，医疗保健费用以及就业和家庭结构的损失，每年超过5000亿美元。与成瘾作斗争不是意志力的问题，而是一场了解药物如何影响大脑并永久改变其功能的战斗。理解成瘾等复杂疾病的细胞和遗传基础的一个关键限制是，是否有好的模型来测试与细胞和基因及其功能相关的假设。实验室大鼠是一种具有巨大价值的模型，因为它具有深入研究的生理，生化和行为特征以及与人类的基因组序列相似性。最初在大鼠中描述了2000多个疾病相关性状的遗传决定因素，然而，由于操纵大鼠基因组的技术限制，很难精确地将特定基因与这些性状相关联。在过去的4年里，我们一直在开发新的工具来缩小这一技术差距。我们已经开发了新的和有效的方法，使转基因大鼠使用转座因子是高度可重复的，我们是第一个应用锌指核酸酶（ZFN）技术的目标和破坏，或敲除，特定的基因在大鼠。这是两项非常重要的技术，使我们能够做很多事情，但还需要做更多的工作。很多时候，在整个动物中敲除一个基因会妨碍研究它在特定细胞或组织中的作用，因为该基因对早期胚胎发育至关重要，因此敲除它会导致动物死亡。在其他情况下，敲除整个动物中的基因并不能让人区分该基因在哪个器官（例如大脑的一部分）中起作用而导致疾病。在这项试点/可行性研究中，我们建议开发实现这一目标的下一个关键技术步骤-能够在特定时间特异性破坏特定细胞或组织中的基因。我们将开发在特定组织中表达诱导型CRE/loxP重组酶系统的转基因大鼠。这个系统将使我们能够创造条件性基因敲除大鼠，我们可以控制何时何地从细胞中移除基因功能。我们将集中研究已知对成瘾和行为研究很重要的脑神经元系统-多巴胺能和多巴胺能神经元。为了证明这个系统的原理，我们将敲除产生血清素的基因，血清素是一种在大脑奖励系统中很重要的激素，也是成瘾和其他精神疾病的重要因素，特别是在后脑神经元中。如果成功，这种方法将改变我们在实验室大鼠模型中处理基因、细胞和疾病的方式，从而影响成瘾和药物滥用的社会经济负担。 公共卫生相关性：开发治疗成瘾和其他精神疾病的有效疗法的关键是识别基因和它们工作的细胞，以靶向新的药物和方法。实验室大鼠是许多资源研究成瘾的首选模型，但通过敲除特定细胞或组织中特定基因的功能来研究特定基因的技术尚未得到证实。这项试点和可行性研究旨在在实验室大鼠中开发该技术，以便我们能够研究特定基因及其在成瘾行为和其他疾病中的作用。

DESCRIPTION (provided by applicant): It is estimated that addiction and its associated costs: crime, domestic violence and child abuse, health care costs, and loss of employment and family structure, exceed half of a trillion dollars per year. Fighting addiction is not a matter of willpower, it is a battle to understand how drugs affect the brain and can permanently alter its function. One of the key limitations to understanding the cellular and genetic basis of a complex disease like addiction is the availability of good models to test hypotheses related to cells and genes and their functions. The laboratory rat is one model which has tremendous value because of its intensely studied physiological, biochemical, and behavioral characteristics and their genome sequence similarities to humans. More than 2000 genetic determinants of disease-related traits have been initially described in the rat, however, it has been difficult to precisely correlate specific genes with these traits because of limitations in technology for manipulating the rat genome. In the past 4 years, we have been developing new tools to close this technology gap. We have developed new and efficient ways of making transgenic rats using transposable elements which are highly reproducible and we were the first to apply zinc-finger nuclease (ZFN) technology to target and disrupt, or knock out, specific genes in the rat. These are two very important technologies that allow us to do many things, but more work is needed. Many times, knocking out a gene in the whole animal precludes studying its role in a particular cell or tissue because the gene is essential for early embryo development and so knocking it out causes the animal to die. In other cases, knocking out the gene in the whole animal doesn't allow one to distinguish what organ (or part of the brain, for example) the gene is functioning in to cause the disease. In this pilot/feasibility study, we propose to develop the next key technological step toward this goal - to be able to specifically disrupt genes in a particular cell or tissue at a particular time. We will develop transgenic rats which express an inducible CRE/loxP recombinase system in specific tissues. This system will allow us to create conditional knockout rats where we can control where and when a gene function is removed from a cell. We will focus brain neuron systems known to be important for studying addiction and behavior - the dopaminergic and serotonergic neurons. As a proof of principal that the system is working, we will knock out the gene that produces serotonin, a hormone that is important in the reward system of the brain and an integral player in addiction and other psychiatric disorders, specifically in neurons of the hindbrain. If successful, this approach will change the way we can approach genes, cells and diseases in the laboratory rat model to impact the socioeconomic burdens of addiction and drug abuse. PUBLIC HEALTH RELEVANCE: The key to developing effective therapies for the treatment of addiction and other psychiatric disorders is the identification of genes and the cells they work in to target new drugs and approaches. Lab rats are the preferred model for studying addiction by many resources, but the technology to study a particular gene by knocking out its function in a particular cell or tissue has not been demonstrated. This pilot and feasibility study aims to develop that technology in the lab rat so we can enable studies of specific genes and their roles in addictive behavior and other diseases.