Figure 1

Prp40 FF domains 1–3 bind to Snu71 I and FF domain 1 binds to Luc7 II. Binding sites of FF domains and Luc7 and Snu71 were roughly mapped by Yeast-2-hybrid assays. A, Two-hybrid assay testing binding of Prp40 FF domain constructs (FF1, FF2, FF3; FF4, FF1-2, FF2-3, FF3-4, FF1-3) to full-length clones and fragments of Snu71 and Luc7 (for domains and fragments see panel B). Each encircled colony indicates a two-hybrid interaction (weak interactions in hatched circles). B, Schematic overview of Prp40 FF domain interactions (arrows) with the U1snRNP proteins Snu71 and Luc7 in the context of the U1snRNP as illustrated by the human U1snRNP (modified after [9]). Note that the structural model of the human U1snRNP does not include any of the proteins studied here. The dashed line extending to the FF1 domain indicates that the full length Snu71 interacts with FF2-3 whereas Snu71-I interacts only with domains FF1-3.