A) Deletion of Sen1 N-terminal domain does not prevent the interaction of Sen1 with RNAPII. CoIP experiments using Rbp3-FLAG as the bait. Assays were performed in a Sen1-AID strain harboring a plasmid expressing either SEN1 or sen1∆Nter upon depletion of Sen1-AID in the presence of IAA for 2h. An asterisk denotes a major proteolytic Sen1 fragment detected in the extracts of roughly the size of sen1∆Nter. Nrd1 is detected as a positive control. Representative gel of one out of two independent experiments. Protein extracts were treated with RNaseA before immunoprecipitation. 