LRRK2 in Parkinson's Disease Neurodegeneration

项目摘要 帕金森病（PD）的患病率预计到2040年将翻一番，但目前还没有治疗方法。 延缓或阻止疾病进展的方法。富含亮氨酸重复序列激酶2（LRRK 2）的广泛作用 家族性和特发性PD中的突变已经出现，将其地位提升为中心疾病目标。最后， 预防LRRK 2神经毒性将需要详细了解驱动LRRK 2神经毒性的关键机制。 神经变性与常见LRRK 2 G2019 S相关的最常见神经元缺陷之一 体外突变是神经突长度和复杂性的损失。然而，这些缺陷在体内的性质， 根本原因，以及它们与多巴胺神经元死亡的关系都是未知的。这就造成了一个主要的 了解疾病病因的障碍。LRRK 2 G2019 S基因修饰子的无偏筛选 神经退行性变导致三个基因的发现; cut和pbl，它们都在神经突中起作用。 生长和维护。这就产生了一个假设，即pblo、cut和pbl驱动LRRK 2 G2019 S。 诱导多巴胺能神经突缺陷，这些缺陷是必要的和足够的多巴胺 老年动物的神经元死亡。在拟议的研究中，LRRK 2 G2019 S对多巴胺能神经突的影响 果蝇衰老过程中的生长和维持将使用条件性转基因来确定， 过表达LRRK 2 G2019 S。LRRK 2 G2019 S表达将在整个寿命期内被诱导， 仅限于发育或衰老，以确定这如何影响在发育中观察到的多巴胺能神经突缺陷。 老苍蝇通过改变LRRK 2 G2019 S神经突缺陷中的cut、cut和pbl机制 将检查细胞骨架调节及其在神经元死亡中的作用。哺乳动物的贡献 与黑质多巴胺神经元损失相关的pb 1（PROX 1）、cut（CUX 1）和pb 1（ECT 2）的直系同源物将被 在LRRK 2 G2019 S诱导的神经变性的大鼠腺病毒模型中评估。成功完成 该研究将有助于理解（i）LRRK 2 G2019 S的分子机制- 体内诱导的神经突缺陷（ii）这些缺陷在体内发育和衰老过程中的性质（iii） 这些缺陷是否是年龄相关的多巴胺神经元死亡的必要和充分条件，以及（iv）是否 所鉴定的修饰物的哺乳动物直向同源物也有助于LRRK 2G 2019 S神经变性。这 预计贡献将是重大的，因为它将提供一个重大的进展，了解 PD中驱动LRRK 2 G2019 S神经变性的机制。这项建议包括若干 概念和技术创新，以实现LRRK 2的性质和机制的详细研究- 相关的神经突缺陷，它们在衰老过程中的动力学以及它们与已建立的PD相关的 表型。

PROJECT SUMMARY Parkinson’s disease (PD) is projected to double in prevalence by 2040 and yet there are no current therapeutic approaches that delay or stop disease progression. A broad role for leucine-rich repeat kinase 2 (LRRK2) mutations in familial and idiopathic PD has emerged, elevating its status to a central disease target. Ultimately, prevention of LRRK2 neurotoxicity will require a detailed understanding of the key mechanisms driving neurodegeneration. One of the most frequent neuronal defects associated with the common LRRK2 G2019S mutation in vitro is a loss of neurite length and complexity. Yet, the nature of these defects in vivo, their underlying cause, and their relationship to dopamine neuron death are all unknown. This creates a major roadblock to understanding disease etiology. An unbiased screen for genetic modifiers of LRRK2 G2019S neurodegeneration lead to the discovery of three genes; prospero, cut and pbl, which all have roles in neurite outgrowth and maintenance. This generates the hypothesis that prospero, cut and pbl drive LRRK2 G2019S- induced dopaminergic neurite defects, and that these defects are necessary and sufficient for dopamine neuron death in aged animals. In the proposed studies, the impact of LRRK2 G2019S on dopaminergic neurite growth and maintenance across aging in Drosophila will be determined using conditional transgenics that overexpress LRRK2 G2019S. LRRK2 G2019S expression will be induced either throughout the life span or restricted to development or aging to determine how this impacts dopaminergic neurite defects observed in aged flies. Mechanisms involving prospero, cut and pbl in LRRK2 G2019S neurite defects through altered cytoskeletal regulation and their role in neuronal death will be examined. The contribution of the mammalian orthologs of prospero (PROX1), cut (CUX1) and pbl (ECT2) to substantia nigra dopamine neuron loss will be assessed in a rat adenoviral model of LRRK2 G2019S-induced neurodegeneration. Successful completion of the proposed research will contribute to the understanding of (i) molecular mechanisms of LRRK2 G2019S- induced neurite defects in vivo (ii) the nature of these defects across development and aging in vivo (iii) whether these defects are necessary and sufficient for age-related dopamine neuron death and (iv) whether the mammalian orthologs of the identified modifiers also contribute to LRRK2 G2019S neurodegeneration. This contribution is expected to be significant because it will provide a major advance in understanding the mechanisms driving LRRK2 G2019S neurodegeneration in PD. This proposal incorporates a number of conceptual and technological innovations to achieve a detailed study of the nature and mechanisms of LRRK2- related neurite defects, their dynamics across aging and their connection to established PD-related phenotypes.