title: Suppression of 15-lipoxygenase synthesis by hnRNP E1 is dependent on repetitive nature of LOX mRNA 3'-UTR control element DICE.
abstract: Cytidine-rich 15-lipoxygenase differentiation control element (15-LOX DICE) is a multifunctional cis-element found in the 3'-UTR of numerous eukaryotic mRNAs. It binds KH domain proteins of the type hnRNP E and K, thus mediating mRNA stabilization and translational control. Translational silencing is caused by formation of a simple binary complex between DICE and recombinant hnRNP E1 (E1). Electromobility shift assays and sucrose gradient centrifugation demonstrate that rabbit 15-LOX DICE, which is composed of ten subunits of the sequence (CCCCPuCCCUCUUCCCCAAG)10=10R, is able to bind up to ten molecules of E1. Protein/RNA interaction was studied with different subunits and submotifs of the 10R structure. Binding appears to be dependent on the degree of polymerization of the C-clusters (1R<2R<4R<10R), but not on their order. The minimal motif, which still functioned in E1 binding, contained two C-clusters (CCCCPuCCCUCUU). For efficient translational control, E1 binding is a necessary, but not sufficient, condition. Translational inhibition by E1 is only observed when at least a dimeric 2R configuration of the DICE is present in the 3'-UTR of a reporter mRNA. We conclude that binding of at least two E1 molecules activate or expose a binding site to enable the complex to interact with the 5'-end of the mRNA and the translational machinery. DICE-motifs are widely distributed in nature. The UTR database UTRnr contains 78 entries of mRNAs with 15-LOX DICEs. Most DICEs were two- to fourfold repetitive, but also highly repetitive structures were found, as in quail myelin protein mRNA (31 repeats) and hyperglycemic hormone mRNA of two crayfish species (nine and 11 repeats).
authors.affiliation: Biomedizinisches Forschungszentrum (BMFZ) University Clinics Charité, Augustenburger Platz 1, Humboldt-University Berlin, D-13353, Germany.
authors.forename: Iris
authors.initials: I
authors.lastname: Reimann
authors.forename: Antje
authors.initials: A
authors.lastname: Huth
authors.forename: Holger
authors.initials: H
authors.lastname: Thiele
authors.forename: Bernd-Joachim
authors.initials: BJ
authors.lastname: Thiele
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics* / Q000378:metabolism; D000818:Animals; D001093:Arachidonate 15-Lipoxygenase / Q000096:biosynthesis* / Q000235:genetics*; D060829:Arthropod Proteins; D003400:Astacoidea / Q000235:genetics; D001483:Base Sequence; D001665:Binding Sites; D002499:Centrifugation, Density Gradient; D004268:DNA-Binding Proteins; D030541:Databases, Genetic; D024202:Electrophoretic Mobility Shift Assay; D017930:Genes, Reporter / Q000235:genetics; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D006801:Humans; D007447:Invertebrate Hormones / Q000235:genetics; D008969:Molecular Sequence Data; D009186:Myelin Sheath / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics; D014176:Protein Biosynthesis / Q000235:genetics*; D011784:Quail / Q000235:genetics; D016601:RNA-Binding Proteins / Q000378:metabolism*; D011817:Rabbits; D012045:Regulatory Sequences, Nucleic Acid / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D016415:Sequence Alignment; D020080:Tandem Repeat Sequences / Q000235:genetics
chemical_list: D020413:3' Untranslated Regions; D060829:Arthropod Proteins; D004268:DNA-Binding Proteins; D034441:Heterogeneous-Nuclear Ribonucleoproteins; D007447:Invertebrate Hormones; D009419:Nerve Tissue Proteins; C094604:PCBP1 protein, human; D016601:RNA-Binding Proteins; C015947:hyperglycemic hormone, crustacean; D001093:Arachidonate 15-Lipoxygenase