Novel suppressors of alpha-synuclein toxicity identified using yeast.
Novel suppressors of alpha-synuclein toxicity identified using yeast.
复制标题
使用酵母鉴定出新型 α-突触核蛋白毒性抑制剂。
DOI：
10.1093/hmg/ddn276
复制
发表时间：
2008
影响因子：
3.5
通讯作者：
Witt,StephanN
中科院分区：
文献类型：
--
作者：
Liang,Jun;Clark-Dixon,Cheryl;Wang,Shaoxiao;Flower,ToddR;Williams-Hart,Tara;Zweig,Richard;Robinson,LucyC;Tatchell,Kelly;Witt,StephanN
帕金森病相关蛋白α-突触核蛋白（α-syn）导致神经退行性变的机制尚未阐明。为了确定保护细胞免受α-syn侵害的基因，我们使用遗传筛选来鉴定表达α-syn的酵母对过氧化氢杀伤的超敏感性的抑制因子。在泛素依赖的蛋白质催化、蛋白质合成、囊泡运输和应激反应中鉴定了40个基因。在40个基因中，ENT 3、IDP 3、JEM 1、ARG 2和HSP 82 5个基因阻断α-syn诱导的活性氧积累的能力最强，并对这5个基因进行了更详细的表征。与表达α-syn的野生型细胞相比，通过生长缺陷判断，这五个基因中的任何一个的缺失增强了α-syn的毒性，这表明这些基因保护细胞免受α-syn的侵害。引人注目的是，这五个基因中有四个对α-syn具有特异性，因为它们不能保护细胞免受两种遗传突变体A30 P或A53 T的毒性。这一发现表明，α-syn通过与这两种遗传突变体不同的途径对细胞产生毒性。最后，Ent 3 p（一种参与高尔基体和液泡之间蛋白质转运的网格蛋白衔接蛋白）的过表达导致α-syn从质膜重新分布到细胞质囊泡结构中。我们的解释是，Ent 3 p介导的运输α-syn到液泡的蛋白水解降解。类似的网格蛋白衔接蛋白epsinR存在于人类中。
The mechanism by which the Parkinson’s disease-related protein α-synuclein (α-syn) causes neurodegeneration has not been elucidated. To determine the genes that protect cells from α-syn, we used a genetic screen to identify suppressors of the super sensitivity of the yeastSaccharomyces cerevisiaeexpressing α-syn to killing by hydrogen peroxide. Forty genes in ubiquitin-dependent protein catabolism, protein biosynthesis, vesicle trafficking and the response to stress were identified. Five of the forty genes—ENT3,IDP3,JEM1,ARG2andHSP82—ranked highest in their ability to block α-syn-induced reactive oxygen species accumulation, and these five genes were characterized in more detail. The deletion of any of these five genes enhanced the toxicity of α-syn as judged by growth defects compared with wild-type cells expressing α-syn, which indicates that these genes protect cells from α-syn. Strikingly, four of the five genes are specific for α-syn in that they fail to protect cells from the toxicity of the two inherited mutants A30P or A53T. This finding suggests that α-syn causes toxicity to cells through a different pathway than these two inherited mutants. Lastly, overexpression of Ent3p, which is a clathrin adapter protein involved in protein transport between the Golgi and the vacuole, causes α-syn to redistribute from the plasma membrane into cytoplasmic vesicular structures. Our interpretation is that Ent3p mediates the transport of α-syn to the vacuole for proteolytic degradation. A similar clathrin adaptor protein, epsinR, exists in humans.