A yeast model of FUS/TLS-dependent cytotoxicity.
A yeast model of FUS/TLS-dependent cytotoxicity.
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DOI：
10.1371/journal.pbio.1001052
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发表时间：
2011-04
期刊：
影响因子：
9.8
通讯作者：
Petsko GA
中科院分区：
文献类型：
--
作者：
Ju S;Tardiff DF;Han H;Divya K;Zhong Q;Maquat LE;Bosco DA;Hayward LJ;Brown RH Jr;Lindquist S;Ringe D;Petsko GA
FUS/TLS是一种核酸结合蛋白，当突变时，可引起家族性肌萎缩侧索硬化症（fALS）的一个子集。虽然FUS/TLS通常主要位于细胞核中，但FUS/TLS的致病突变形式运输到受影响的脊髓运动神经元或神经胶质细胞的细胞质中并在其中形成内含物。在这里，我们报告了一个酵母模型的人FUS/TLS表达，概括了多个显着特征的病理致病突变蛋白，包括核质易位，包涵体形成，细胞毒性。蛋白质结构域分析表明，羧基端的FUS/TLS，其中大多数ALS相关的突变聚集，是必需的，但不足以为蛋白质的毒性。使用酵母过表达文库的全基因组遗传筛选鉴定了由酵母基因ECM 32、NAM 8、SBP 1、SKO 1和VHR 1编码的五种酵母DNA/RNA结合蛋白，其拯救人FUS/TLS的毒性而不改变其表达水平、胞质易位或包涵体形成。此外，ECM 32的人类同源物hUPF 1也在该模型中挽救了FUS/TLS的毒性，验证了酵母模型并暗示了在FUS/TLS介导的毒性机制中RNA加工或RNA质量控制机制的可能不足。检查FUS/TLS表达对酵母中选定mRNA衰变的影响表明，无义介导的衰变途径可能不是毒性或抑制的主要决定因素。在肉体所承受的上千种自然冲击中，最具破坏性的一种是肌萎缩侧索硬化症（ALS），俗称卢伽雷病。这种疾病有遗传和随机两种形式，其特征是脊髓运动神经元变性，导致瘫痪和死亡。散发性形式的原因尚不清楚，但新的见解来自于研究导致更罕见的家族性形式的遗传变异。一个这样的基因，占遗传性ALS的5%-10%，是FUS/TLS，它编码一种蛋白质，通常生活在细胞核中，并参与信使RNA（mRNA）的生命周期。FUS/TLS中ALS相关突变导致蛋白质错误定位在细胞核外进入应激颗粒。了解错误定位的FUS/TLS毒性的基础可能会导致ALS治疗的新方法。我们已经建立了FUS/TLS细胞毒性的酵母模型，该模型概括了错误定位、颗粒积聚和细胞死亡。我们已经利用酵母模型来获得关于蛋白质的哪一部分是正确定位所需的以及哪一部分是毒性所必需的信息。我们还鉴定了几种人类基因，当它们在酵母中过表达时，能够将细胞从错误定位的FUS/TLS的毒性中拯救出来。这些基因都具有mRNA质量控制的功能，暗示了ALS病理学中该途径的变化。
FUS/TLS is a nucleic acid binding protein that, when mutated, can cause a subset of familial amyotrophic lateral sclerosis (fALS). Although FUS/TLS is normally located predominantly in the nucleus, the pathogenic mutant forms of FUS/TLS traffic to, and form inclusions in, the cytoplasm of affected spinal motor neurons or glia. Here we report a yeast model of human FUS/TLS expression that recapitulates multiple salient features of the pathology of the disease-causing mutant proteins, including nuclear to cytoplasmic translocation, inclusion formation, and cytotoxicity. Protein domain analysis indicates that the carboxyl-terminus of FUS/TLS, where most of the ALS-associated mutations are clustered, is required but not sufficient for the toxicity of the protein. A genome-wide genetic screen using a yeast over-expression library identified five yeast DNA/RNA binding proteins, encoded by the yeast genes ECM32, NAM8, SBP1, SKO1, and VHR1, that rescue the toxicity of human FUS/TLS without changing its expression level, cytoplasmic translocation, or inclusion formation. Furthermore, hUPF1, a human homologue of ECM32, also rescues the toxicity of FUS/TLS in this model, validating the yeast model and implicating a possible insufficiency in RNA processing or the RNA quality control machinery in the mechanism of FUS/TLS mediated toxicity. Examination of the effect of FUS/TLS expression on the decay of selected mRNAs in yeast indicates that the nonsense-mediated decay pathway is probably not the major determinant of either toxicity or suppression. Of all the thousand natural shocks that flesh is heir to, one of the most devastating is amyotrophic lateral sclerosis (ALS), commonly known as Lou Gehrig's Disease. This disorder, which comes in both inherited and random forms, is characterized by degeneration of spinal motor neurons, leading to paralysis and death. The cause of the sporadic form is unknown, but new insight has come from studying the genetic variations that lead to the rarer familial forms. One such gene, accounting for 5%–10% of inherited ALS, is FUS/TLS, which encodes a protein that normally lives in the nucleus of the cell and is involved in the life-cycle of messenger RNA (mRNA). ALS-associated mutations in FUS/TLS cause the protein to mislocalize outside the nucleus into stress granules. Understanding the basis for the toxicity of mislocalized FUS/TLS could lead to new approaches to the treatment of ALS. We have made a yeast model for FUS/TLS cellular toxicity that recapitulates the mislocalization, granular accumulation, and cell death. We have exploited the yeast model to obtain information about what part of the protein is required for proper localization and what part is essential for toxicity. We have also identified several human genes that, when over-expressed in yeast, are able to rescue the cell from the toxicity of mislocalized FUS/TLS. These genes all have functions in mRNA quality control, implicating changes in this pathway in the pathology of ALS.
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影响因子：
56.9
作者：
Kwiatkowski, T. J., Jr.;Bosco, D. A.;Brown, R. H., Jr.
通讯作者：
Brown, R. H., Jr.
影响因子：
14.5
作者：
Neumann, Manuela;Rademakers, Rosa;Mackenzie, Ian R. A.
通讯作者：
Mackenzie, Ian R. A.
影响因子：
12.7
作者：
Neumann M;Roeber S;Kretzschmar HA;Rademakers R;Baker M;Mackenzie IR
通讯作者：
Mackenzie IR
影响因子：
9.8
作者：
Chen, YZ;Bennett, CL;Chance, PF
通讯作者：
Chance, PF
影响因子：
--
作者：
Hewitt, Christopher;Kirby, Janine;Shaw, Pamela J.
通讯作者：
Shaw, Pamela J.