title: ELAV, a Drosophila neuron-specific protein, mediates the generation of an alternatively spliced neural protein isoform.
abstract: BACKGROUND
  Tissue-specific alternative pre-mRNA splicing is a widely used mechanism for gene regulation and the generation of different protein isoforms, but relatively little is known about the factors and mechanisms that mediate this process. Tissue-specific RNA-binding proteins could mediate alternative pre-mRNA splicing. In Drosophila melanogaster, the RNA-binding protein encoded by the elav (embryonic lethal abnormal visual system) gene is a candidate for such a role. The ELAV protein is expressed exclusively in neurons, and is important for the formation and maintenance of the nervous system.
  
  
  RESULTS
  In this study, photoreceptor neurons genetically depleted of ELAV, and elav-null central nervous system neurons, were analyzed immunocytochemically for the expression of neural proteins. In both situations, the lack of ELAV corresponded with a decrease in the immunohistochemical signal of the neural-specific isoform of Neuroglian, which is generated by alternative splicing. Furthermore, when ELAV was expressed ectopically in cells that normally express only the non-neural isoform of Neuroglian, we observed the generation of the neural isoform of Neuroglian.
  
  
  CONCLUSIONS
  Drosophila ELAV promotes the generation of the neuron-specific isoform of Neuroglian by the regulation of pre-mRNA splicing. The findings reported in this paper demonstrate that ELAV is necessary, and the ectopic expression of ELAV in imaginal disc cells is sufficient, to mediate neuron-specific alternative splicing.
authors.affiliation: Biology Department, Brandeis University, Waltham, Massachusetts 02254, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Koushika
authors.forename: M J
authors.initials: MJ
authors.lastname: Lisbin
authors.forename: K
authors.initials: K
authors.lastname: White
mesh_terms: D017398:Alternative Splicing; D000818:Animals; D015816:Cell Adhesion Molecules, Neuronal / Q000235:genetics*; D002490:Central Nervous System / Q000378:metabolism; D029721:Drosophila Proteins; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism; D051959:ELAV Proteins; D005260:Female; D017353:Gene Deletion; D005786:Gene Expression Regulation; D008297:Male; D009474:Neurons / Q000378:metabolism; D009479:Neuropeptides / Q000235:genetics* / Q000378:metabolism; D017933:Peripheral Nervous System / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics*; D012261:Ribonucleoproteins / Q000235:genetics*; D014158:Transcription, Genetic
chemical_list: D015816:Cell Adhesion Molecules, Neuronal; D029721:Drosophila Proteins; D051959:ELAV Proteins; D009479:Neuropeptides; D016601:RNA-Binding Proteins; D012261:Ribonucleoproteins; C061745:Nrg protein, Drosophila