Shared RNA-binding sites for interacting members of the Drosophila ELAV family of neuronal proteins.
The product of the Drosophila embryonic lethal abnormal visual system is a conserved protein (ELAV) necessary for normal neuronal differentiation and maintenance. It possesses three RNA-binding domains and is involved in the regulation of RNA metabolism. The long elav 3'-untranslated region (3'-UTR) is necessary for autoregulation. We used RNA-binding assays and in vitro selection to identify the ELAV best binding site in the elav 3'-UTR. This site resembles ELAV-binding sites identified previously in heterologous targets, both for its nucleotide sequence and its significant affinity for ELAV (K(d) 40 nM). This finding supports our model that elav autoregulation depends upon direct interaction between ELAV and elav RNA. We narrowed down the best binding site to a 20 nt long sequence A(U5)A(U3)G(U2)A(U6) in an alternative 3' exon. We propose and test a model in which the regulated use of this alternative 3' exon is involved in normal elav regulation. Found in NEurons (FNE), another neuronal RNA-binding protein paralogous to ELAV, also binds this site. These observations provide a molecular basis for the in vivo interactions reported previously between elav and fne.
Borgeson
Claudia D
CD
Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, Omaha, NE 68198-4525, USA.
Samson
Marie-Laure
ML
D020413:3' Untranslated Regions / Q000737:chemistry* / Q000378:metabolism; D017398:Alternative Splicing; D020816:Amino Acid Motifs; D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D004330:Drosophila / Q000235:genetics* / Q000378:metabolism; D029721:Drosophila Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D051959:ELAV Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005091:Exons; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D014158:Transcription, Genetic
D020413:3' Untranslated Regions; D029721:Drosophila Proteins; D051959:ELAV Proteins; C498009:ELAV protein, Drosophila; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; C473066:fne protein, Drosophila