The Molecular Basis of NCL

描述（由申请人提供）：神经元蜡样质脂褐质沉积症（NCL）是一种复发性遗传性儿童疾病，在美国的发病率约为1：12，500。NCL是一种选择性受损的线粒体自噬问题，因为CNS中的神经元细胞以ATP合酶亚基c在自发荧光沉积物中的积累为特征。遗传证据导致不同的NCL基因座调节线粒体自噬的不同步骤的假设。大多数NCL病例（JNCL; Batten病）是由于CLN 3中的基因组缺失突变，其破坏了battenin，一种涉及pH调节的内体/溶酶体膜蛋白。更严重的变异晚期婴儿（vLINCL）形式的疾病是由CLN 6突变引起的。实现我们以前的目标，我们已经确定了CLN 6，它编码linclin，一种膜蛋白，可能定位于内质网（ER）。除了不同的亚细胞定位，linclin和battenin与不同的伴侣蛋白。在该更新申请中，我们提出使用遗传vLINCL Cln 6 [nclf]和JNCL Cln 3 [delta-ex 7/8]小鼠和细胞培养模型，其表现出在患者细胞中观察到的缺陷，以描绘需要linclin和battenin功能的神经元细胞中线粒体自噬的离散步骤。目的1将测试的假设，linclin和battenin功能在野生型神经元细胞的线粒体自噬需要在专门的ER和内体/溶酶体室的活动，分别。目的2将评估是否候选伴侣蛋白牵连linclin或battenin功能所需的正常线粒体自噬在野生型神经元细胞。目的3将确定vLINCL和JNCL突变是否阻断纯合突变型Cln 6 [nclf]和Cln 3 [delta-ex 7/8]神经元细胞中线粒体自噬的不同步骤。目的4将通过鉴定FDA批准的可以改变Cln 6 [nclf]和Cln 3 [delta-ex 7/8]神经元细胞中的异常表型的化合物来检验线粒体功能障碍可能与受损的线粒体自噬相关的假设。这些研究有望揭示linclin和battenin在神经元细胞线粒体自噬中的活性，阐明JNCL和vLINCL的病理生理学，并促进这些破坏性疾病的有效疗法的开发。

DESCRIPTION (provided by applicant): The neuronal ceroid lipofuscinosis (NCLs) are recessively inherited childhood disorders, with an incidence of approximately 1:12,500 in the U.S. NCL is a problem of selectively impaired mitochondrial autophagy, as neuronal cells in the CNS feature the accumulation of ATP synthase subunit c in autofluorescent deposits. The genetic evidence leads to the hypothesis that different NCL loci regulate distinct steps in mitochondrial autophagy. Most cases of NCL (JNCL; Batten disease) are due to a genomic deletion mutation in CLN3 that disrupts battenin, an endosomal/lysosomal membrane protein implicated in pH regulation. The more severe variant late infantile (vLINCL) form of the disease is caused by mutations in CLN6. Fulfilling our previous aims, we have identified CLN6, which encodes linclin, a membrane protein that may localize to the endoplasmic reticulum (ER). In addition to different subcellular localizations, linclin and battenin associate with different sets of partner proteins. In this renewal application, we propose to use genetic vLINCL Cln6[nclf] and JNCL Cln3 [delta-ex7/8] mouse and cell culture models, which exhibit deficits observed in patient cells, to delineate the discrete steps in mitochondrial autophagy in neuronal cells that require linclin and battenin function. Aim 1 will test the hypothesis that linclin and battenin functions in mitochondrial autophagy in wild-type neuronal cells entail activities in specialized ER and endosomal/lysosomal compartments, respectively. Aim 2 will assess whether candidate partner proteins implicated in linclin or battenin function are required for normal mitochondrial autophagy in wild-type neuronal cells. Aim 3 will determine whether vLINCL and JNCL mutations block different steps in mitochondrial autophagy in homozygous mutant Cln6[nclf] and Cln3[delta-ex7/8] neuronal cells. Aim 4 will test the hypothesis that mitochondrial dysfunction may be linked to impaired mitochondrial autophagy, by identifying FDA approved compounds that may alter both abnormal phenotypes in Cln6[nclf] and Cln3[delta-ex7/8] neuronal cells. These studies are expected to uncover linclin and battenin activities in mitochondrial autophagy in neuronal cells, shedding light on the pathophysiology of JNCL and vLINCL and spurring the development of effective therapies for these devastating disorders.