ROLES FOR ALPHA-SYNUCLEIN DEGRADATION AND CYTOSOLIC DOPAMINE IN PD PATHOGENESIS

我们将展开一系列调查，发现包括错误处理α+核蛋白在内的“多次命中”。 (a-syn)降解，2)细胞内钙，3)细胞内多巴胺(DA)，帕金森病的基础 疾病(PD)。我们的初步结果表明，如果这些因素中的任何一个在神经元培养中缺失 选择性黑质(SN)死亡的模型，神经退行性变可以被阻断。 在之前的Udall时期，我们1)发展了细胞内斑片电化学(IPE)来测量胞浆 多巴胺(MoSharov等人，2003；MoSharov等人，2006b)和2)报告了a-syn被特定降解 在专门的溶酶体中通过伴侣介导的自噬(CMA)，但致病的a-syn突变体 和DA修饰的α-SYN(DA-SYN)阻断CMA(Cuervo等人，2004年；Martinez-Vicente等人，2008年)。 在当前的提案中，我们描述了a-syn如何被运输到溶酶体并阻止CMA(目标1)如何 胞浆Ca~(++)控制黑质神经元胞质DA(AIM 2)以及这三种“HITS”是如何结合的 扰乱正常的动态平衡，并可能导致小鼠的病理改变(目标3)。

We will extend a line of investigation that suggests that "multiple hits", consisting of mishandling of 1) alphasynuclein (a-syn) degradation, 2) cytosolic calcium, and 3) cytosolic dopamine (DA), underlie Parkinson's disease (PD). Our preliminary results indicate that if any of these factors are absent in neuronal culture models of selective substantia nigra (SN) death, neurodegeneration can be blocked. During the prior Udall period, we 1) developed intracellular patch electrochemistry (IPE) to measure cytosolic dopamine (Mosharov et al., 2003; Mosharov et al., 2006b) and 2) reported that a-syn is specifically degraded within specialized lysosomes by chaperone-mediated autophagy (CMA), but that pathogenic a-syn mutants and DA-modified-a-syn (DA-syn) block CMA (Cuervo et al., 2004; Martinez-Vicente et al., 2008). In the current proposal, we characterize how a-syn is trafficked to lysosomes and blocks CMA (Aim 1) how cytosolic Ca++ controls cytosolic DA in SN neurons (Aim 2) and how the combination of these three "hits" disturbs normal homeostasis and may cause in pathology in mice (Aim 3).