Mayer A, Schreieck A, Lidschreiber M, Leike K, Martin DE, Cramer1 P
During transcription elongation, RNA polymerase (Pol) II binds the general elongation factor Spt5. Spt5 contains a repetitive C-terminal region (CTR) that is required for co-transcriptional recruitment of the Paf1 complex (44, 88). Here we report a new role of the Spt5 CTR in the recruitment of 3’-RNA processing factors. Chromatin immunoprecipitation (ChIP) reveals that the Spt5 CTR is required for normal recruitment of the pre-mRNA cleavage factor (CF) I to the 3’-end of yeast genes. RNA contributes to CFI recruitment, as RNase treatment prior to ChIP further decreases CFI ChIP signals. Genome-wide ChIP profiling detects occupancy peaks of CFI subunits around 100 nucleotides downstream of the poly-adenylation (pA) site of genes. CFI recruitment to this defined region may result from simultaneous binding to the Spt5 CTR, to nascent RNA containing the pA sequence, and to the elongating Pol II isoform that is phosphorylated at serine 2 (S2) residues in its C-terminal domain (CTD). Consistent with this model, the CTR interacts with CFI in vitro, but is not required for pA site recognition and transcription termination in vivo.