Combined use of MS2 and PP7 coat fusions shows that TIA-1 dominates hnRNP A1 for K-SAM exon splicing control.
Splicing of the FGFR2 K-SAM exon is repressed by hnRNP A1 bound to the exon and activated by TIA-1 bound to the downstream intron. Both proteins are expressed similarly by cells whether they splice the exon or not, so it is important to know which one is dominant. To answer this question, we used bacteriophage PP7 and bacteriophage MS2 coat fusions to tether hnRNP A1 and TIA-1 to distinct sites on the same pre-mRNA molecule. hnRNP A1 fused to one coat protein was tethered to a K-SAM exon containing the corresponding coat protein's binding site. TIA-1 fused to the other coat protein was tethered to the downstream intron containing that coat protein's binding site. This led to efficient K-SAM exon splicing. Our results show that TIA-1 is dominant for K-SAM exon splicing control and validate the combined use of PP7 and MS2 coat proteins for studying posttranscriptional events.
INSERM, U892, 8 quai Moncousu, BP 70721, 44007 Nantes Cedex 1, France.
Marie-Claude
MC
Gesnel
Fabienne
F
Del Gatto-Konczak
Richard
R
Breathnach
D017398:Alternative Splicing; D001435:Bacteriophages / Q000235:genetics*; D036022:Capsid Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D003001:Cloning, Molecular; D005091:Exons; D000076245:Heterogeneous Nuclear Ribonucleoprotein A1; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D017909:Levivirus / Q000235:genetics; D039102:Poly(A)-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D012322:RNA Precursors / Q000235:genetics / Q000378:metabolism; D051497:Receptor, Fibroblast Growth Factor, Type 2 / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D000074019:T-Cell Intracellular Antigen-1
D036022:Capsid Proteins; D000076245:Heterogeneous Nuclear Ribonucleoprotein A1; D034481:Heterogeneous-Nuclear Ribonucleoprotein Group A-B; D039102:Poly(A)-Binding Proteins; D012322:RNA Precursors; D011993:Recombinant Fusion Proteins; D000074019:T-Cell Intracellular Antigen-1; C071558:TIA1 protein, human; C496353:FGFR2 protein, human; D051497:Receptor, Fibroblast Growth Factor, Type 2