Structural and functional analysis of RNA and TAP binding to SF2/ASF.
The serine/arginine-rich (SR) protein splicing factor 2/alternative splicing factor (SF2/ASF) has a role in splicing, stability, export and translation of messenger RNA. Here, we present the structure of the RNA recognition motif (RRM) 2 from SF2/ASF, which has an RRM fold with a considerably extended loop 5 region, containing a two-stranded beta-sheet. The loop 5 extension places the previously identified SR protein kinase 1 docking sequence largely within the RRM fold. We show that RRM2 binds to RNA in a new way, by using a tryptophan within a conserved SWQLKD motif that resides on helix alpha1, together with amino acids from strand beta2 and a histidine on loop 5. The linker connecting RRM1 and RRM2 contains arginine residues, which provide a binding site for the mRNA export factor TAP, and when TAP binds to this region it displaces RNA bound to RRM2.
Department of Molecular Biology and Biotechnology, University of Sheffield, Firth Court, Western Bank, Sheffield S10 2TN, UK.
Aura M
AM
Tintaru
Guillaume M
GM
Hautbergue
Andrea M
AM
Hounslow
Ming-Lung
ML
Hung
Lu-Yun
LY
Lian
C Jeremy
CJ
Craven
Stuart A
SA
Wilson
D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry* / Q000235:genetics; D029543:Nucleocytoplasmic Transport Proteins / Q000737:chemistry*; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry; D017433:Protein Structure, Secondary; D012326:RNA Splicing; D012333:RNA, Messenger / Q000737:chemistry* / Q000235:genetics; D016601:RNA-Binding Proteins / Q000737:chemistry*; D000068103:Serine-Arginine Splicing Factors; D014364:Tryptophan / Q000737:chemistry / Q000235:genetics
C122111:NXF1 protein, human; D009687:Nuclear Proteins; D029543:Nucleocytoplasmic Transport Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D000068103:Serine-Arginine Splicing Factors; D014364:Tryptophan; D001120:Arginine; C087728:SRPK1 protein, human; D017346:Protein Serine-Threonine Kinases