Yhh1p/Cft1p directly links poly(A) site recognition and RNA polymerase II transcription termination.
RNA polymerase II (pol II) transcription termination requires co-transcriptional recognition of a functional polyadenylation signal, but the molecular mechanisms that transduce this signal to pol II remain unclear. We show that Yhh1p/Cft1p, the yeast homologue of the mammalian AAUAAA interacting protein CPSF 160, is an RNA-binding protein and provide evidence that it participates in poly(A) site recognition. Interestingly, RNA binding is mediated by a central domain composed of predicted beta-propeller-forming repeats, which occurs in proteins of diverse cellular functions. We also found that Yhh1p/Cft1p bound specifically to the phosphorylated C-terminal domain (CTD) of pol II in vitro and in a two-hybrid test in vivo. Furthermore, transcriptional run-on analysis demonstrated that yhh1 mutants were defective in transcription termination, suggesting that Yhh1p/Cft1p functions in the coupling of transcription and 3'-end formation. We propose that direct interactions of Yhh1p/Cft1p with both the RNA transcript and the CTD are required to communicate poly(A) site recognition to elongating pol II to initiate transcription termination.
Dichtl
Bernhard
B
Department of Cell Biology, Biozentrum, University of Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland. bernhard.dichtl@unibas.ch
Blank
Diana
D
Sadowski
Martin
M
Hübner
Wolfgang
W
Weiser
Stefan
S
Keller
Walter
W
D000199:Actins; D000595:Amino Acid Sequence; D001665:Binding Sites; D004926:Escherichia coli; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D010441:Peptide Chain Elongation, Translational; D010443:Peptide Chain Termination, Translational / Q000502:physiology*; D011061:Poly A / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D012319:RNA Polymerase II / Q000502:physiology*; D012331:RNA, Fungal / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D011993:Recombinant Fusion Proteins / Q000502:physiology; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D020798:Two-Hybrid System Techniques; D039221:mRNA Cleavage and Polyadenylation Factors
C465210:Act1 protein, S cerevisiae; D000199:Actins; C465209:Cft1 protein, S cerevisiae; D046911:Macromolecular Substances; D012331:RNA, Fungal; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D029701:Saccharomyces cerevisiae Proteins; D039221:mRNA Cleavage and Polyadenylation Factors; D011061:Poly A; D012319:RNA Polymerase II