The resulting fusion gene product, EWS/NOR1, has been believed to lead to malignant transformation by functioning as a transcriptional activator, but an alternative mechanism may also be involved.     ///    The EWS/NOR1 fusion gene product gains a novel activity affecting pre-mRNA splicing..     ///    "To verify the potential function of EWS/NOR1 in mammalian cells, we next showed that overexpression of EWS/NOR1 caused increased usage of the distal 5'-splice site of pre-mRNA splicing and that EWS/NOR1 interacted with the human splicing protein U1C. "    ///    neither EWS nor NOR1 had the same activity or interaction as EWS/NOR1.     ///    "Altogether, our findings reveal that EWS/NOR1 gains a novel activity affecting pre-mRNA splicing.. "    ///    "Here, using a newly developed functional complementation screening in yeast, we found that EWS/NOR1, but not EWS or NOR1, complemented the loss of function of the small nuclear ribonucleoprotein Snu23p, an essential factor for pre-mRNA splicing in yeast. "