Knoop L L, Baker S J
Department of Developmental Neurobiology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA.
J Biol Chem. 2001 Jun 22;276(25):22317-22. doi: 10.1074/jbc.M008950200. Epub 2001 Apr 11.
The chimeric gene EWS/FLI is present in at least 85% of Ewing's sarcomas as a result of chromosomal translocations. The resulting fusion protein contains the N terminus of the RNA-binding protein EWS and the ETS DNA-binding domain of the transcription factor FLI-1. Although EWS/FLI binds DNA and activates transcription, both EWS and EWS/FLI also interact with SF1 and U1C, essential components of the splicing machinery. Therefore, we tested the ability of EWS and EWS/FLI to alter 5'-splice site selection using an E1A gene in vivo splicing assay. We found that EWS/FLI, but not EWS, interfered with heterogeneous nuclear ribonucleoprotein A1-dependent splice site selection of E1A. Mutational analysis of EWS/FLI revealed that the ability to affect pre-mRNA splicing coincided with transforming activity. Therefore, EWS/FLI has the ability to influence splicing as well as transcription.
由于染色体易位，嵌合基因EWS/FLI存在于至少85%的尤因肉瘤中。所产生的融合蛋白包含RNA结合蛋白EWS的N端和转录因子FLI-1的ETS DNA结合结构域。尽管EWS/FLI能结合DNA并激活转录，但EWS和EWS/FLI也都与剪接机制的重要组成部分SF1和U1C相互作用。因此，我们使用E1A基因体内剪接试验测试了EWS和EWS/FLI改变5'-剪接位点选择的能力。我们发现EWS/FLI而非EWS干扰了E1A的异质性核核糖核蛋白A1依赖性剪接位点选择。EWS/FLI的突变分析表明，影响前体mRNA剪接的能力与转化活性一致。因此，EWS/FLI有能力影响剪接以及转录。
