title: Identification of a purine-rich intronic enhancer element in the mouse eosinophil-associated ribonuclease 2 (mEar 2) gene.
abstract: The Mus musculus eosinophil-associated ribonuclease (mEar) gene cluster includes multiple distinct coding sequences that are highly divergent orthologs of the human eosinophil ribonucleases, eosinophil-derived neurotoxin (EDN/RNase 2) and eosinophil cationic protein (ECP/RNase 3). We present a transcriptional analysis of the gene encoding mEar 2, the only member of this cluster with a well-defined expression profile. In this work, we demonstrate that the presence of non-coding exon 1 and the intron in tandem with a 361-bp 5' promoter of mEar 2 results in enhanced reporter gene expression, as much as 6-to 10-fold over the activity observed with the 5' promoter alone. We have identified a conserved purine-rich element in the intron of the mEar 2 gene that is necessary for maximum transcription and that interacts specifically with NFAT-binding proteins in nuclear extracts derived from the mouse LA4 epithelial cell line. Similar intronic enhancers have been described as regulating transcription of the human EDN gene, suggesting an overall conservation of an important regulatory strategy.
authors.affiliation: Eosinophil Pathophysiology Section, LHD, NIAID, National Institutes of Health, Bethesda, Maryland 20892, USA. kdyer@niaid.nih.gov
authors.forename: Kimberly D
authors.initials: KD
authors.lastname: Dyer
authors.forename: Takeaki
authors.initials: T
authors.lastname: Nitto
authors.forename: Joanne M
authors.initials: JM
authors.lastname: Moreau
authors.forename: Amanda L
authors.initials: AL
authors.lastname: McDevitt
authors.forename: Helene F
authors.initials: HF
authors.lastname: Rosenberg
mesh_terms: D000818:Animals; D001483:Base Sequence; D001665:Binding Sites / Q000235:genetics; D001798:Blood Proteins / Q000235:genetics; D045744:Cell Line, Tumor; D017931:DNA Primers; D030541:Databases, Genetic; D024202:Electrophoretic Mobility Shift Assay; D004742:Enhancer Elements, Genetic / Q000235:genetics*; D047091:Eosinophil Granule Proteins; D047208:Eosinophil-Derived Neurotoxin; D015870:Gene Expression; D017930:Genes, Reporter / Q000235:genetics; D007438:Introns / Q000235:genetics; D051379:Mice / Q000235:genetics*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010802:Phylogeny; D011687:Purines / Q000032:analysis; D012260:Ribonucleases / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D001798:Blood Proteins; D017931:DNA Primers; D047091:Eosinophil Granule Proteins; D011687:Purines; C479821:Ear2 protein, mouse; D047208:Eosinophil-Derived Neurotoxin; D012260:Ribonucleases