Selection of a subset of mRNAs from combinatorial 3' untranslated region libraries using neuronal RNA-binding protein Hel-N1.
Hel-N1, a human RNA-binding protein, shares significant homology with Drosophila protein ELAV, which is essential for fly neuronal development. Hel-N1 has been shown to bind in vitro to 3' untranslated regions of mRNAs encoding c-myc, c-fos, granulocyte/macrophage colony-stimulating factor, and transcriptional repressor, Id. We report that Hel-N1 and a related form, Hel-N2, are expressed in human medulloblastoma cells, but their ratio differs significantly from that in adult brain and fetal brain. Selection of RNA targets from randomized combinatorial libraries yielded (A+U)-rich consensus sequences for both Hel-N1 and Hel-N2. As a means to identify cellular RNA targets for these proteins, we devised combinatorial shape libraries representing naturally derived 3' untranslated regions and were able to select a structurally related subset of transcripts that bound to Hel-N1. Approximately 10% of the proteins encoded by these subset mRNAs were identifiable in the data bases and most are implicated in cell growth regulation. This approach provides a means to gain access to novel genes expressed in various cell types by partitioning mRNAs containing common sequence elements using RNA-binding proteins.
Department of Microbiology, Duke University Medical Center, Durham, NC 27710.
F B
FB
Gao
C C
CC
Carson
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T
Levine
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JD
Keene
D001483:Base Sequence; D001921:Brain / Q000502:physiology*; D003001:Cloning, Molecular; D016384:Consensus Sequence; D051959:ELAV Proteins; D000067777:ELAV-Like Protein 2; D015870:Gene Expression; D015723:Gene Library; D006367:HeLa Cells; D006801:Humans; D066298:In Vitro Techniques; D008024:Ligands; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D012333:RNA, Messenger / Q000302:isolation & purification*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D014407:Tumor Cells, Cultured
D051959:ELAV Proteins; D000067777:ELAV-Like Protein 2; C086811:ELAVL2 protein, human; D008024:Ligands; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D016601:RNA-Binding Proteins