Aggregation of ALS-linked FUS mutant sequesters RNA binding proteins and impairs RNA granules formation.
Aggregation of ALS-linked FUS mutant sequesters RNA binding proteins and impairs RNA granules formation.
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ALS 连接的 FUS 突变体的聚集会隔离 RNA 结合蛋白并损害 RNA 颗粒的形成。
DOI：
10.1016/j.bbrc.2014.08.115
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Atsushi Yamaguchi
中科院分区：
文献类型：
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作者：
Keisuke Takanashi;Atsushi Yamaguchi
蛋白质聚集/包涵体是肌萎缩侧索硬化（amyotrophiclateralsclerosis，ALS）等神经退行性疾病的标志之一，FUS/TLS基因是家族性ALS的致病基因之一，编码一种多功能的DNA/RNA结合蛋白，主要定位于细胞核。FUS/TLS中的C-末端突变导致FUS/TLS突变体在细胞质中的保留和包含。在本研究中，我们研究了ALS相关的RNA结合蛋白和RNA颗粒的ALS连锁FUS突变体的影响。在瞬时转染的SH-SY 5 Y细胞中，FUS C-末端突变体作为小颗粒广泛错误定位在细胞质中，而在约10%的这些细胞中自发形成大的聚集体。hnRNP A1、hnRNP A2和SMN 1以及FUS野生型在应激条件下组装成应激颗粒，并且这些也被募集到细胞质中的FUS突变体衍生的自发聚集体中。这些聚集体使poly（A）mRNA停滞，并将SMN 1隔离在去污剂不溶性部分中，这也减少了FISH（荧光原位杂交）试验中核寡核苷酸（dT）阳性病灶（斑点）的数量。此外，在含有FUS P525 L的细胞质颗粒的细胞中，P体的数量减少。这些发现提出了ALS连接的C-末端FUS突变体可以在细胞质聚集体中螯合各种RNA结合蛋白和mRNA的可能性，这可能会破坏RNA平衡和生物发生的各个方面。
Protein aggregate/inclusion is one of hallmarks for neurodegenerative disorders including amyotrophic lateral sclerosis (ALS).FUS/TLS, one of causative genes for familial ALS, encodes a multifunctional DNA/RNA binding protein predominantly localized in the nucleus. C-terminal mutations inFUS/TLScause the retention and the inclusion of FUS/TLS mutants in the cytoplasm. In the present study, we examined the effects of ALS-linked FUS mutants on ALS-associated RNA binding proteins and RNA granules. FUS C-terminal mutants were diffusely mislocalized in the cytoplasm as small granules in transiently transfected SH-SY5Y cells, whereas large aggregates were spontaneously formed in ∼10% of those cells. hnRNP A1, hnRNP A2, and SMN1 as well as FUS wild type were assembled into stress granules under stress conditions, and these were also recruited to FUS mutant-derived spontaneous aggregates in the cytoplasm. These aggregates stalled poly(A) mRNAs and sequestered SMN1 in the detergent insoluble fraction, which also reduced the number of nuclear oligo(dT)-positive foci (speckles) in FISH (fluorescencein situhybridization) assay. In addition, the number of P-bodies was decreased in cells harboring cytoplasmic granules of FUS P525L. These findings raise the possibility that ALS-linked C-terminal FUS mutants could sequester a variety of RNA binding proteins and mRNAs in the cytoplasmic aggregates, which could disrupt various aspects of RNA equilibrium and biogenesis.