A novel function for the U2AF 65 splicing factor in promoting pre-mRNA 3'-end processing.
Splicing and 3'-end processing (including cleavage and polyadenylation) of vertebrate pre-mRNAs are tightly coupled events that contribute to the extensive molecular network that coordinates gene expression. Sequences within the terminal intron of genes are essential to stimulate pre-mRNA 3'-end processing, although the factors mediating this effect are unknown. Here, we show that the pyrimidine tract of the last splice acceptor site of the human beta-globin gene is necessary to stimulate mRNA 3'-end formation in vivo and binds the U2AF 65 splicing factor. Naturally occurring beta-thalassaemia-causing mutations within the pyrimidine tract reduces both U2AF 65 binding and 3'-end cleavage efficiency. Significantly, a fusion protein containing U2AF 65, when tethered upstream of a cleavage/polyadenylation site, increases 3'-end cleavage efficiency in vitro and in vivo. Therefore, we propose that U2AF 65 promotes 3'-end processing, which contributes to 3'-terminal exon definition.
Millevoi
Stefania
S
Nuclear Biology Group, Division of Medical and Molecular Genetics, GKT School of Medicine, Guy's Hospital, London Bridge, London, UK.
Geraghty
Finola
F
Idowu
Bernadine
B
Tam
Jennifer L Y
JL
Antoniou
Michael
M
Vagner
Stéphan
S
D002467:Cell Nucleus / Q000378:metabolism; D005091:Exons; D006801:Humans; D009154:Mutation; D009687:Nuclear Proteins; D010957:Plasmids / Q000378:metabolism; D017354:Point Mutation; D011233:Precipitin Tests; D017434:Protein Structure, Tertiary; D011743:Pyrimidines / Q000378:metabolism; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism; D012261:Ribonucleoproteins / Q000502:physiology*; D015719:Single-Strand Specific DNA and RNA Endonucleases / Q000378:metabolism; D000072668:Splicing Factor U2AF; D014162:Transfection; D014466:Ultraviolet Rays; D017086:beta-Thalassemia / Q000235:genetics
D009687:Nuclear Proteins; D011743:Pyrimidines; D012333:RNA, Messenger; D012261:Ribonucleoproteins; D000072668:Splicing Factor U2AF; C000607494:U2AF2 protein, human; D015719:Single-Strand Specific DNA and RNA Endonucleases