Determining whether metabolic and mitochondrial pathophysiology are a common feature of three distinct genetic models of ASD

在过去的20年里，数百种潜在的自闭症遗传风险因素已经被确定。的 然而，这些基因位点与自闭症相关的机制知之甚少，但有许多线索 都来自于动物模型的使用。脆性X综合征（FXS）、1型神经纤维瘤病（NF 1）和 Neurexin 1基因（NRX 1）缺失是三种常见的单基因形式的自闭症， FMR 1、NF 1和NRX 1基因功能的丧失。最近的临床研究结果表明，此外， 与这些疾病相关的众所周知的行为和认知症状，受影响的个人也 存在多种全身表型和代谢异常，可能是由于多效性效应 FMR 1、NF 1和NRX 1基因。这些发现与最近的证据表明线粒体 在智力残疾相关综合征和自闭症的发病机制中的功能障碍。 我们之前的研究，以及其他人的研究，已经发现果蝇和哺乳动物的模型， FXS和NF 1具有强大的细胞信号级联缺陷，包括cAMP减少和cAMP增加。 胰岛素/PI 3 K信号转导。我们的实验室和其他实验室， 已经证明增加cAMP水平足以恢复果蝇的行为和认知， FXS和NF 1的鼠模型。我们还表明，在果蝇模型中，胰岛素信号的减少 FXS改善昼夜节律和记忆表型。 在我们提出的研究中，我们探讨了三种果蝇模型中的线粒体功能， 确定线粒体缺陷是否存在，如果存在，定义共性和差异 在他们中间。我们还将探讨已确定的信号通路缺陷对线粒体的影响。 在NF 1和FXS模型中起作用，以确定线粒体活性是否可能受到这些信号传导的影响 缺陷，从而有助于这些模型显示的表型。

In the last twenty years hundreds of potential genetic risk factors for autism have been identified. The mechanisms by which these genetic loci are linked to autism however are poorly understood, but many clues are coming from the use of animal models. Fragile X Syndrome (FXS), neurofibromatosis type 1 (NF1), and deletions in the Neurexin 1 gene (NRX1) are three such prevalent monogenic forms of autism, that are caused by loss of FMR1, NF1, and NRX1 gene function, respectively. Recent clinical findings suggest that, in addition to the well known behavioral and cognitive symptoms associated with these diseases, affected individuals also present with a variety of systemic phenotypes and metabolic abnormalities, likely due to the pleiotropic effects of the FMR1, NF1, and NRX1 genes. These findings come in hand with recent evidence implicating mitochondrial dysfunction in the pathogenesis of intellectual disability related syndromes and autism. Our prior studies, as well as that of others, have uncovered that Drosophila and mammalian models of FXS and NF1 have robust cellular signaling cascade defects, including decreased cAMP and increased insulin/PI3K signaling. The importance of these signaling defects is shown by the fact that our lab and others, have demonstrated that increasing cAMP levels is sufficient to restore behavior and cognition in Drosophila and murine models of FXS and NF1. We have also shown that reduction of insulin signaling in the Drosophila model of FXS ameliorates circadian and memory phenotypes. In our proposed studies we explore mitochondrial function in three Drosophila models of monogenetic forms of autism to determine if mitochondrial defects exist and if so, define commonalities and differences amongst them. We will also explore the impact that identified signaling pathway defects have on mitochondrial function in the NF1 and FXS models to determine if mitochondrial activity may be impacted by these signaling defects and thus contribute to the phenotypes displayed by these models.