Specific splicing defects in S. pombe carrying a degron allele of the Survival of Motor Neuron gene
Specific splicing defects in S. pombe carrying a degron allele of the Survival of Motor Neuron gene
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DOI：
10.1038/emboj.2010.70
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发表时间：
2010-06-02
期刊：
影响因子：
11.4
通讯作者：
Bordonne, Remy
中科院分区：
文献类型：
--
作者：
Campion, Yannick;Neel, Henry;Bordonne, Remy
脊髓性肌萎缩症是运动神经元 (SMN1) 存活基因缺失或突变造成的。 SMN 蛋白在剪接体 snRNP 的生物合成中具有重要作用，但该过程中的缺陷与前 mRNA 的特异性剪接抑制之间的联系尚未确定。在这项研究中，我们报道了粟酒裂殖酵母 SMN 蛋白的温度降解决定子 (td) 等位基因的构建，并表明其在 37 摄氏度下的损耗会影响 U1、U2、U4 和 U5 snRNP 的剪接和形成，但不会影响 U6 和 U3 核糖核蛋白的剪接和形成。 snRNP 组装中 tdSMN 等位基因的功能在 25 摄氏度时已经受到干扰，表明标签在该温度下会产生有害影响。使用全基因组方法，我们报告内含子对 tdSMN 细胞中较低水平的 snRNP 的反应不均匀，并且增加聚嘧啶束的长度可以提高一些但不是全部受影响内含子的剪接效率。总而言之，我们的结果表明，在 tdSMN 裂殖酵母细胞中观察到的缺陷类似于在 SMN 缺陷的后生动物细胞中观察到的剪接缺陷。 EMBO 杂志 (2010) 29, 1817-1829。 doi：10.1038/emboj.2010.70； 2010 年 4 月 16 日在线发布
Spinal muscular atrophy results from deletions or mutations in the survival of motor neuron (SMN1) gene. The SMN protein has an essential role in the biogenesis of spliceosomal snRNPs, but the link between a defect in this process and specific splicing inhibition of pre-mRNAs has not been established. In this study, we report the construction of a temperature-degron (td) allele of the Schizosaccharomyces pombe SMN protein and show that its depletion at 37 degrees C affects splicing and formation of U1, U2, U4 and U5 snRNPs, but not of U6 and U3 ribonucleoproteins. The function of the tdSMN allele in snRNP assembly is already perturbed at 25 degrees C, suggesting a deleterious effect of the tag at this temperature. Using a genome-wide approach, we report that introns react unequally to lower levels of snRNPs in tdSMN cells and that increasing the length of the polypyrimidine tract can improve the splicing efficiency of some, but not all, affected introns. Altogether, our results suggest that the defects observed in tdSMN fission yeast cells mimic splicing deficits observed in SMN-deficient metazoan cells. The EMBO Journal (2010) 29, 1817-1829. doi:10.1038/emboj.2010.70; Published online 16 April 2010