The U2AF35-related protein Urp contacts the 3' splice site to promote U12-type intron splicing and the second step of U2-type intron splicing.
The U2AF35-related protein Urp has been implicated previously in splicing of the major class of U2-type introns. Here we show that Urp is also required for splicing of the minor class of U12-type introns. Urp is recruited in an ATP-dependent fashion to the U12-type intron 3' splice site, where it promotes formation of spliceosomal complexes. Remarkably, Urp also contacts the 3' splice site of a U2-type intron, but in this case is specifically required for the second step of splicing. Thus, through recognition of a common splicing element, Urp facilitates distinct steps of U2- and U12-type intron splicing.
Department of Life Science, Gwangju Institute of Science and Technology, Gwangju 500-712, Korea. haihongshen@gist.ac.kr
Haihong
H
Shen
Xuexiu
X
Zheng
Stephan
S
Luecke
Michael R
MR
Green
D000595:Amino Acid Sequence; D000818:Animals; D006367:HeLa Cells; D006801:Humans; D015151:Immunoblotting; D007438:Introns / Q000235:genetics*; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D010802:Phylogeny; D034622:RNA Interference; D022821:RNA Splice Sites / Q000235:genetics*; D012326:RNA Splicing; D012342:RNA, Small Nuclear / Q000235:genetics*; D012261:Ribonucleoproteins / Q000235:genetics / Q000378:metabolism*; D017381:Spliceosomes / Q000378:metabolism; D000072668:Splicing Factor U2AF
D009687:Nuclear Proteins; D022821:RNA Splice Sites; D012342:RNA, Small Nuclear; D012261:Ribonucleoproteins; D000072668:Splicing Factor U2AF; C096986:U12 small nuclear RNA; C405484:U2 small nuclear RNA; C076753:U2AF1 protein, human; C484334:ZRSR2 protein, human