Strauss E J, Guthrie C
Department of Biochemistry, University of California, San Francisco 94143-0448.
Nucleic Acids Res. 1994 Aug 11;22(15):3187-93. doi: 10.1093/nar/22.15.3187.
We previously reported the isolation of PRP28, a gene in Saccharomyces cerevisiae whose activity is required for the first step of nuclear mRNA splicing in vivo. Sequence analysis revealed that PRP28 is included in the 'DEAD-box' gene family, members of which are thought to function as ATP-dependent RNA helicases. Genetic interactions led us to suggest that PRP28 is functionally associated with the U4/U5/U6 snRNP. We have now purified the PRP28 protein from S. cerevisiae and demonstrated that it is required for the first step of splicing in vitro. Interestingly, PRP28 is not a stably associated snRNP protein. Strand displacement assays indicate that PRP28 does not exhibit RNA helicase activity, suggesting that an additional factor or factors may be required for its activation.
我们之前报道过酿酒酵母中PRP28基因的分离，该基因的活性是体内核mRNA剪接第一步所必需的。序列分析表明PRP28属于“DEAD-box”基因家族，该家族成员被认为作为依赖ATP的RNA解旋酶发挥作用。遗传相互作用使我们推测PRP28在功能上与U4/U5/U6 snRNP相关。我们现在已经从酿酒酵母中纯化出PRP28蛋白，并证明它是体外剪接第一步所必需的。有趣的是，PRP28不是一种稳定结合的snRNP蛋白。链置换分析表明PRP28不表现出RNA解旋酶活性，这表明其激活可能需要一个或多个其他因子。
