title: A Non-sequence-specific double-stranded RNA structural element regulates splicing of two mutually exclusive exons of fibroblast growth factor receptor 2 (FGFR2).
abstract: Alternative splicing of fibroblast growth factor receptor 2 (FGFR2) mutually exclusive exons IIIb and IIIc represents a tightly regulated and functionally relevant example of post-transcriptional gene regulation. Rat prostate cancer DT3 and AT3 cell lines demonstrate exclusive selection of either exon IIIb or exon IIIc, respectively, and have been used to characterize regulatory FGFR2 RNA cis-elements that are required for splicing regulation. Two sequences termed ISE-2 and ISAR are located in the intron between exons IIIb and IIIc and are required for cell-type specific exon IIIb. Previous studies suggest that the function of these elements involves formation of an RNA stem structure, even though they are separated by more than 700 nucleotides. Using transfected minigenes, we performed a systematic analysis of the sequence and structural components of ISE-2 and ISAR that are required for their ability to regulate FGFR2 splicing. We found that the primary sequence of these elements can be replaced by completely unrelated sequences, provided that they are also predicted to form an RNA stem structure. Thus, a nonsequence-specific double stranded RNA stem constitutes a functional element required for FGFR2 splicing; suggesting that a double-stranded RNA binding protein is a component of the splicing regulatory machinery.
authors.affiliation: Renal-Electrolyte and Hypertension Division, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-6144, USA.
authors.forename: Stephanie J
authors.initials: SJ
authors.lastname: Muh
authors.forename: Ruben H
authors.initials: RH
authors.lastname: Hovhannisyan
authors.forename: Russ P
authors.initials: RP
authors.lastname: Carstens
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D017124:Conserved Sequence; D005091:Exons; D005786:Gene Expression Regulation; D006801:Humans; D007438:Introns; D051379:Mice; D008954:Models, Biological; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D012326:RNA Splicing; D012330:RNA, Double-Stranded / Q000737:chemistry*; D051381:Rats; D020794:Receptor Protein-Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics*; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051497:Receptor, Fibroblast Growth Factor, Type 2; D017468:Receptors, Fibroblast Growth Factor / Q000096:biosynthesis / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014162:Transfection; D014407:Tumor Cells, Cultured; D014981:Xenopus; D029867:Xenopus Proteins
chemical_list: D012330:RNA, Double-Stranded; D017468:Receptors, Fibroblast Growth Factor; D029867:Xenopus Proteins; D012313:RNA; C496348:FGFR1 protein, human; C496353:FGFR2 protein, human; C496349:Fgfr1 protein, mouse; C496350:Fgfr1 protein, rat; C496357:Fgfr2 protein, Xenopus; C496354:Fgfr2 protein, mouse; C496356:Fgfr2 protein, rat; D020794:Receptor Protein-Tyrosine Kinases; D051496:Receptor, Fibroblast Growth Factor, Type 1; D051497:Receptor, Fibroblast Growth Factor, Type 2