Séraphin B, Abovich N, Rosbash M
Howard Hughes Medical Institute, Department of Biology, Brandeis University, Waltham, MA 02254.
Nucleic Acids Res. 1991 Jul 25;19(14):3857-60. doi: 10.1093/nar/19.14.3857.
The pre-mRNA splicing pathway is highly conserved from yeast (S. cerevisiae) to mammals. Of the four snRNPs involved in splicing three (U1, U2 and U4/U6) have been shown to be essential for in vitro splicing. To examine the remaining snRNP, we utilized our previously described genetic procedures (Seraphin and Rosbash, 1989) to prepare yeast extracts depleted of U5 snRNP. The results show that U5 snRNP is necessary for both steps of pre- mRNA splicing and for proper spliceosome assembly, i.e., addition of the U4/U5/U6 triple snRNP. The prior steps of U1 and U2 snRNP addition occur normally in the absence of U5 snRNP.
从前体mRNA剪接途径从酵母（酿酒酵母）到哺乳动物都高度保守。在参与剪接的四种小核核糖核蛋白颗粒（snRNP）中，已证明其中三种（U1、U2和U4/U6）对于体外剪接至关重要。为了研究剩余的snRNP，我们利用之前描述的遗传方法（Seraphin和Rosbash，1989年）制备了缺乏U5 snRNP的酵母提取物。结果表明，U5 snRNP对于前体mRNA剪接的两个步骤以及正确的剪接体组装（即添加U4/U5/U6三小核核糖核蛋白颗粒）都是必需的。在没有U5 snRNP的情况下，添加U1和U2 snRNP的先前步骤正常发生。
