Department of Biology, Emory University, Atlanta, GA 30322, USA.
Graduate Program in Biochemistry, Cell and Developmental Biology, James T. Laney Graduate School, Emory University, Atlanta, GA 30322, USA.
Nucleic Acids Res. 2018 Jul 27;46(13):6561-6575. doi: 10.1093/nar/gky446.
The polyadenosine RNA-binding protein ZC3H14 is important in RNA processing. Although ZC3H14 is ubiquitously expressed, mutation of the ZC3H14 gene causes a non-syndromic form of intellectual disability. Here, we examine the function of ZC3H14 in the brain by identifying ZC3H14-interacting proteins using unbiased mass spectrometry. Through this analysis, we identified physical interactions between ZC3H14 and multiple RNA processing factors. Notably, proteins that comprise the THO complex were amongst the most enriched proteins. We demonstrate that ZC3H14 physically interacts with THO components and that these proteins are required for proper RNA processing, as loss of ZC3H14 or THO components leads to extended bulk poly(A) tail length. Furthermore, we identified the transcripts Atp5g1 and Psd95 as shared RNA targets of ZC3H14 and the THO complex. Our data suggest that ZC3H14 and the THO complex are important for proper processing of Atp5g1 and Psd95 RNA, as depletion of ZC3H14 or THO components leads to decreased steady-state levels of each mature transcript accompanied by accumulation of Atp5g1 and Psd95 pre-mRNA in the cytoplasm. Taken together, this work provides the first unbiased identification of nuclear ZC3H14-interacting proteins from the brain and links the functions of ZC3H14 and the THO complex in the processing of RNA.
多聚腺苷酸 RNA 结合蛋白 ZC3H14 在 RNA 处理中很重要。尽管 ZC3H14 广泛表达，但 ZC3H14 基因的突变会导致一种非综合征形式的智力残疾。在这里，我们通过使用无偏质谱法鉴定 ZC3H14 相互作用蛋白来研究 ZC3H14 在大脑中的功能。通过这项分析，我们鉴定了 ZC3H14 与多个 RNA 处理因子之间的物理相互作用。值得注意的是，THO 复合物的组成蛋白是最丰富的蛋白之一。我们证明 ZC3H14 与 THO 成分之间存在物理相互作用，并且这些蛋白是正确的 RNA 处理所必需的，因为 ZC3H14 或 THO 成分的缺失会导致大量 poly(A) 尾延长。此外，我们还鉴定了 Atp5g1 和 Psd95 作为 ZC3H14 和 THO 复合物的共同 RNA 靶标。我们的数据表明，ZC3H14 和 THO 复合物对于 Atp5g1 和 Psd95 RNA 的正确处理很重要，因为 ZC3H14 或 THO 成分的耗竭会导致每个成熟转录物的稳态水平降低，同时细胞质中 Atp5g1 和 Psd95 前体 RNA 的积累。总之，这项工作首次提供了从大脑中无偏鉴定核 ZC3H14 相互作用蛋白的方法，并将 ZC3H14 和 THO 复合物的功能联系起来，参与 RNA 的处理。
