Formation and toxicity of peripherin inclusions

描述（由申请人提供）： 运动神经元中存在中间纤维异常内含物（IFS） 神经元是肌萎缩侧索硬化的共同病理特征。 硬化症（ALS）。这些包涵体中的大多数由 神经丝（NF）蛋白与外周蛋白，一种III型IF，通常 在运动神经元中低水平表达。最近，我们发现， 小鼠中野生型外周蛋白的过度表达引起了 IF包涵体和运动神经元迟发性死亡。而且 疾病是由NF轻（NF-L）蛋白水平的缺乏引起的， 与ALS相关的一种现象。这里提出了一些实验， 进一步确定外周蛋白异常是否可能导致ALS 发病机制我们将产生一种新的转基因小鼠模型， 外周蛋白包涵体的形成，由多西环素调控， 转基因表达我们将研究调节形成的机制， 外周蛋白聚集体在神经元中的毒性。先前的结果表明， 通过促炎细胞因子和通过免疫调节剂上调外周蛋白表达 兴奋性毒性损伤建议使用培养的细胞和 转基因小鼠方法，以进一步确定调控元件 激活外周蛋白基因转录，并确定是否诱导 外周蛋白水平有助于脑缺血后的神经元损失， 兴奋性毒性损伤此外，基因敲除方法将使我们能够 确定外周蛋白对两个已建立的 运动神经元疾病的小鼠模型，表达突变型超氧化物的小鼠 与肌萎缩侧索硬化症相关的歧化酶和携带摇摆突变的小鼠。最后我们 将在家族性和散发性病例中寻找外周蛋白基因突变， 人症

DESCRIPTION (provided by applicant): The presence of abnormal inclusions of intermediate filaments (IFS) in motor neurons represents a common pathological feature of amyotrophic lateral sclerosis (ALS). The majority of these inclusion bodies are composed of neurofilament (NF) proteins together with peripherin, a type III IF normally expressed at low levels in motor neurons. Recently, we discovered that the overexpression of wild-type peripherin proteins in mice provokes the formation of IF inclusion bodies and late-onset death of motor neurons. Moreover, the disease was precipitated by a deficiency in levels of NF light (NF-L) proteins, a phenomenon associated with ALS. A number of experiments are proposed here to further determine whether peripherin abnormalities may contribute to ALS pathogenesis. We will generate a new transgenic mouse model with the onset of peripherin inclusion formation, modulated by the doxycycline control of transgene expression. We will study the mechanisms regulating the formation and toxicity of peripherin aggregates in neurons. Previous results demonstrated an upregulation of peripherin expression by pro-inflammatory cytokines and by excitotoxic injury. It is proposed, with the use of cultured cells and of transgenic mouse approaches, to further define the regulatory elements activating peripherin gene transcription and to determine whether induction of peripherin levels contributes to neuronal loss after cerebral ischemia and excitotoxic injury. In addition, the gene knockout approach will allow us to determine the contribution of peripherin to pathogenesis in two established mouse models of motor neuron disease, mice expressing mutant superoxide dismutase linked to ALS and mice carrying the wobbler mutation. Finally, we will search for peripherin gene mutations in familial and sporadic cases of ALS.