Weidenhammer E M, Ruiz-Noriega M, Woolford J L
Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Mol Cell Biol. 1997 Jul;17(7):3580-8. doi: 10.1128/MCB.17.7.3580.
The PRP31 gene encodes a factor essential for the splicing of pre-mRNA in Saccharomyces cerevisiae. Cell extracts derived from a prp31-1 strain fail to form mature spliceosomes upon heat inactivation, although commitment complexes and prespliceosome complexes are detected under these conditions. Coimmunoprecipitation experiments indicate that Prp31p is associated both with the U4/U6 x U5 tri-snRNP and, independently, with the prespliceosome prior to assembly of the tri-snRNP into the splicing complex. Nondenaturing gel electrophoresis and glycerol gradient analyses demonstrate that while Prp31p may play a role in maintaining the assembly or stability of tri-snRNPs, functional protein is not essential for the formation of U4/U6 or U4/U6 x U5 snRNPs. These results suggest that Prp31p is involved in recruiting the U4/U6 x U5 tri-snRNP to prespliceosome complexes or in stabilizing these interactions.
PRP31基因编码一种对酿酒酵母中前体mRNA剪接至关重要的因子。从prp31-1菌株获得的细胞提取物在热失活后无法形成成熟的剪接体，尽管在这些条件下可检测到承诺复合物和前剪接体复合物。免疫共沉淀实验表明，Prp31p与U4/U6×U5三小核核糖核蛋白相关，并且在三小核核糖核蛋白组装到剪接复合物之前独立地与前剪接体相关。非变性凝胶电泳和甘油梯度分析表明，虽然Prp31p可能在维持三小核核糖核蛋白的组装或稳定性中起作用，但功能性蛋白对于U4/U6或U4/U6×U5小核核糖核蛋白的形成并非必不可少。这些结果表明，Prp31p参与将U4/U6×U5三小核核糖核蛋白招募到前剪接体复合物中或稳定这些相互作用。
